Update dh.c #12

HelenHZhang · 2024-02-12T14:12:07Z

here, converting bytes to u64, we need to right shift 3, not 6.
At line 445,
*key_size = n << 3;

here, converting bytes to u64, we need to right shift 3, not 6.

HelenHZhang · 2024-02-13T17:09:44Z

Greg:
Could you explain why you closed my PR?
Could I ask a question about this code?
Could I request any comment about my change?
Thanks

gregkh · 2024-02-13T17:16:35Z

This is not how kernel development is done at all, please read the documentation in the kernel source tree.

This tree is merely a mirror of a git.kernel.org tree for people who are stuck with github to pull from to sync their trees. It is NOT for development at all.

commit cacea81 upstream. nvif_vmm_put gets called if addr is set, but if the allocation fails we don't need to call put, otherwise we get a warning like [523232.435671] ------------[ cut here ]------------ [523232.435674] WARNING: CPU: 8 PID: 1505697 at drivers/gpu/drm/nouveau/nvif/vmm.c:68 nvif_vmm_put+0x72/0x80 [nouveau] [523232.435795] Modules linked in: uinput rfcomm snd_seq_dummy snd_hrtimer nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink qrtr bnep sunrpc binfmt_misc intel_rapl_msr intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common isst_if_common iwlmvm nfit libnvdimm vfat fat x86_pkg_temp_thermal intel_powerclamp mac80211 snd_soc_avs snd_soc_hda_codec coretemp snd_hda_ext_core snd_soc_core snd_hda_codec_realtek kvm_intel snd_hda_codec_hdmi snd_compress snd_hda_codec_generic ac97_bus snd_pcm_dmaengine snd_hda_intel libarc4 snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec kvm iwlwifi snd_hda_core btusb snd_hwdep btrtl snd_seq btintel irqbypass btbcm rapl snd_seq_device eeepc_wmi btmtk intel_cstate iTCO_wdt cfg80211 snd_pcm asus_wmi bluetooth intel_pmc_bxt iTCO_vendor_support snd_timer ledtrig_audio pktcdvd snd mei_me [523232.435828] sparse_keymap intel_uncore i2c_i801 platform_profile wmi_bmof mei pcspkr ioatdma soundcore i2c_smbus rfkill idma64 dca joydev acpi_tad loop zram nouveau drm_ttm_helper ttm video drm_exec drm_gpuvm gpu_sched crct10dif_pclmul i2c_algo_bit nvme crc32_pclmul crc32c_intel drm_display_helper polyval_clmulni nvme_core polyval_generic e1000e mxm_wmi cec ghash_clmulni_intel r8169 sha512_ssse3 nvme_common wmi pinctrl_sunrisepoint uas usb_storage ip6_tables ip_tables fuse [523232.435849] CPU: 8 PID: 1505697 Comm: gnome-shell Tainted: G W 6.6.0-rc7-nvk-uapi+ #12 [523232.435851] Hardware name: System manufacturer System Product Name/ROG STRIX X299-E GAMING II, BIOS 1301 09/24/2021 [523232.435852] RIP: 0010:nvif_vmm_put+0x72/0x80 [nouveau] [523232.435934] Code: 00 00 48 89 e2 be 02 00 00 00 48 c7 04 24 00 00 00 00 48 89 44 24 08 e8 fc bf ff ff 85 c0 75 0a 48 c7 43 08 00 00 00 00 eb b3 <0f> 0b eb f2 e8 f5 c9 b2 e6 0f 1f 44 00 00 90 90 90 90 90 90 90 90 [523232.435936] RSP: 0018:ffffc900077ffbd8 EFLAGS: 00010282 [523232.435937] RAX: 00000000fffffffe RBX: ffffc900077ffc00 RCX: 0000000000000010 [523232.435938] RDX: 0000000000000010 RSI: ffffc900077ffb38 RDI: ffffc900077ffbd8 [523232.435940] RBP: ffff888e1c4f2140 R08: 0000000000000000 R09: 0000000000000000 [523232.435940] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888503811800 [523232.435941] R13: ffffc900077ffca0 R14: ffff888e1c4f2140 R15: ffff88810317e1e0 [523232.435942] FS: 00007f933a769640(0000) GS:ffff88905fa00000(0000) knlGS:0000000000000000 [523232.435943] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [523232.435944] CR2: 00007f930bef7000 CR3: 00000005d0322001 CR4: 00000000003706e0 [523232.435945] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [523232.435946] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [523232.435964] Call Trace: [523232.435965] <TASK> [523232.435966] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436051] ? __warn+0x81/0x130 [523232.436055] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436138] ? report_bug+0x171/0x1a0 [523232.436142] ? handle_bug+0x3c/0x80 [523232.436144] ? exc_invalid_op+0x17/0x70 [523232.436145] ? asm_exc_invalid_op+0x1a/0x20 [523232.436149] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436230] ? nvif_vmm_put+0x64/0x80 [nouveau] [523232.436342] nouveau_vma_del+0x80/0xd0 [nouveau] [523232.436506] nouveau_vma_new+0x1a0/0x210 [nouveau] [523232.436671] nouveau_gem_object_open+0x1d0/0x1f0 [nouveau] [523232.436835] drm_gem_handle_create_tail+0xd1/0x180 [523232.436840] drm_prime_fd_to_handle_ioctl+0x12e/0x200 [523232.436844] ? __pfx_drm_prime_fd_to_handle_ioctl+0x10/0x10 [523232.436847] drm_ioctl_kernel+0xd3/0x180 [523232.436849] drm_ioctl+0x26d/0x4b0 [523232.436851] ? __pfx_drm_prime_fd_to_handle_ioctl+0x10/0x10 [523232.436855] nouveau_drm_ioctl+0x5a/0xb0 [nouveau] [523232.437032] __x64_sys_ioctl+0x94/0xd0 [523232.437036] do_syscall_64+0x5d/0x90 [523232.437040] ? syscall_exit_to_user_mode+0x2b/0x40 [523232.437044] ? do_syscall_64+0x6c/0x90 [523232.437046] entry_SYSCALL_64_after_hwframe+0x6e/0xd8 Reported-by: Faith Ekstrand <[email protected]> Cc: [email protected] Signed-off-by: Dave Airlie <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>

commit cacea81 upstream. nvif_vmm_put gets called if addr is set, but if the allocation fails we don't need to call put, otherwise we get a warning like [523232.435671] ------------[ cut here ]------------ [523232.435674] WARNING: CPU: 8 PID: 1505697 at drivers/gpu/drm/nouveau/nvif/vmm.c:68 nvif_vmm_put+0x72/0x80 [nouveau] [523232.435795] Modules linked in: uinput rfcomm snd_seq_dummy snd_hrtimer nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink qrtr bnep sunrpc binfmt_misc intel_rapl_msr intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common isst_if_common iwlmvm nfit libnvdimm vfat fat x86_pkg_temp_thermal intel_powerclamp mac80211 snd_soc_avs snd_soc_hda_codec coretemp snd_hda_ext_core snd_soc_core snd_hda_codec_realtek kvm_intel snd_hda_codec_hdmi snd_compress snd_hda_codec_generic ac97_bus snd_pcm_dmaengine snd_hda_intel libarc4 snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec kvm iwlwifi snd_hda_core btusb snd_hwdep btrtl snd_seq btintel irqbypass btbcm rapl snd_seq_device eeepc_wmi btmtk intel_cstate iTCO_wdt cfg80211 snd_pcm asus_wmi bluetooth intel_pmc_bxt iTCO_vendor_support snd_timer ledtrig_audio pktcdvd snd mei_me [523232.435828] sparse_keymap intel_uncore i2c_i801 platform_profile wmi_bmof mei pcspkr ioatdma soundcore i2c_smbus rfkill idma64 dca joydev acpi_tad loop zram nouveau drm_ttm_helper ttm video drm_exec drm_gpuvm gpu_sched crct10dif_pclmul i2c_algo_bit nvme crc32_pclmul crc32c_intel drm_display_helper polyval_clmulni nvme_core polyval_generic e1000e mxm_wmi cec ghash_clmulni_intel r8169 sha512_ssse3 nvme_common wmi pinctrl_sunrisepoint uas usb_storage ip6_tables ip_tables fuse [523232.435849] CPU: 8 PID: 1505697 Comm: gnome-shell Tainted: G W 6.6.0-rc7-nvk-uapi+ gregkh#12 [523232.435851] Hardware name: System manufacturer System Product Name/ROG STRIX X299-E GAMING II, BIOS 1301 09/24/2021 [523232.435852] RIP: 0010:nvif_vmm_put+0x72/0x80 [nouveau] [523232.435934] Code: 00 00 48 89 e2 be 02 00 00 00 48 c7 04 24 00 00 00 00 48 89 44 24 08 e8 fc bf ff ff 85 c0 75 0a 48 c7 43 08 00 00 00 00 eb b3 <0f> 0b eb f2 e8 f5 c9 b2 e6 0f 1f 44 00 00 90 90 90 90 90 90 90 90 [523232.435936] RSP: 0018:ffffc900077ffbd8 EFLAGS: 00010282 [523232.435937] RAX: 00000000fffffffe RBX: ffffc900077ffc00 RCX: 0000000000000010 [523232.435938] RDX: 0000000000000010 RSI: ffffc900077ffb38 RDI: ffffc900077ffbd8 [523232.435940] RBP: ffff888e1c4f2140 R08: 0000000000000000 R09: 0000000000000000 [523232.435940] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888503811800 [523232.435941] R13: ffffc900077ffca0 R14: ffff888e1c4f2140 R15: ffff88810317e1e0 [523232.435942] FS: 00007f933a769640(0000) GS:ffff88905fa00000(0000) knlGS:0000000000000000 [523232.435943] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [523232.435944] CR2: 00007f930bef7000 CR3: 00000005d0322001 CR4: 00000000003706e0 [523232.435945] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [523232.435946] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [523232.435964] Call Trace: [523232.435965] <TASK> [523232.435966] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436051] ? __warn+0x81/0x130 [523232.436055] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436138] ? report_bug+0x171/0x1a0 [523232.436142] ? handle_bug+0x3c/0x80 [523232.436144] ? exc_invalid_op+0x17/0x70 [523232.436145] ? asm_exc_invalid_op+0x1a/0x20 [523232.436149] ? nvif_vmm_put+0x72/0x80 [nouveau] [523232.436230] ? nvif_vmm_put+0x64/0x80 [nouveau] [523232.436342] nouveau_vma_del+0x80/0xd0 [nouveau] [523232.436506] nouveau_vma_new+0x1a0/0x210 [nouveau] [523232.436671] nouveau_gem_object_open+0x1d0/0x1f0 [nouveau] [523232.436835] drm_gem_handle_create_tail+0xd1/0x180 [523232.436840] drm_prime_fd_to_handle_ioctl+0x12e/0x200 [523232.436844] ? __pfx_drm_prime_fd_to_handle_ioctl+0x10/0x10 [523232.436847] drm_ioctl_kernel+0xd3/0x180 [523232.436849] drm_ioctl+0x26d/0x4b0 [523232.436851] ? __pfx_drm_prime_fd_to_handle_ioctl+0x10/0x10 [523232.436855] nouveau_drm_ioctl+0x5a/0xb0 [nouveau] [523232.437032] __x64_sys_ioctl+0x94/0xd0 [523232.437036] do_syscall_64+0x5d/0x90 [523232.437040] ? syscall_exit_to_user_mode+0x2b/0x40 [523232.437044] ? do_syscall_64+0x6c/0x90 [523232.437046] entry_SYSCALL_64_after_hwframe+0x6e/0xd8 Reported-by: Faith Ekstrand <[email protected]> Cc: [email protected] Signed-off-by: Dave Airlie <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>

…SR-IOV When kdump kernel tries to copy dump data over SR-IOV, LPAR panics due to NULL pointer exception: Kernel attempted to read user page (0) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on read at 0x00000000 Faulting instruction address: 0xc000000020847ad4 Oops: Kernel access of bad area, sig: 11 [gregkh#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries Modules linked in: mlx5_core(+) vmx_crypto pseries_wdt papr_scm libnvdimm mlxfw tls psample sunrpc fuse overlay squashfs loop CPU: 12 PID: 315 Comm: systemd-udevd Not tainted 6.4.0-Test102+ gregkh#12 Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_008) hv:phyp pSeries NIP: c000000020847ad4 LR: c00000002083b2dc CTR: 00000000006cd18c REGS: c000000029162ca0 TRAP: 0300 Not tainted (6.4.0-Test102+) MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 48288244 XER: 00000008 CFAR: c00000002083b2d8 DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 1 ... NIP _find_next_zero_bit+0x24/0x110 LR bitmap_find_next_zero_area_off+0x5c/0xe0 Call Trace: dev_printk_emit+0x38/0x48 (unreliable) iommu_area_alloc+0xc4/0x180 iommu_range_alloc+0x1e8/0x580 iommu_alloc+0x60/0x130 iommu_alloc_coherent+0x158/0x2b0 dma_iommu_alloc_coherent+0x3c/0x50 dma_alloc_attrs+0x170/0x1f0 mlx5_cmd_init+0xc0/0x760 [mlx5_core] mlx5_function_setup+0xf0/0x510 [mlx5_core] mlx5_init_one+0x84/0x210 [mlx5_core] probe_one+0x118/0x2c0 [mlx5_core] local_pci_probe+0x68/0x110 pci_call_probe+0x68/0x200 pci_device_probe+0xbc/0x1a0 really_probe+0x104/0x540 __driver_probe_device+0xb4/0x230 driver_probe_device+0x54/0x130 __driver_attach+0x158/0x2b0 bus_for_each_dev+0xa8/0x130 driver_attach+0x34/0x50 bus_add_driver+0x16c/0x300 driver_register+0xa4/0x1b0 __pci_register_driver+0x68/0x80 mlx5_init+0xb8/0x100 [mlx5_core] do_one_initcall+0x60/0x300 do_init_module+0x7c/0x2b0 At the time of LPAR dump, before kexec hands over control to kdump kernel, DDWs (Dynamic DMA Windows) are scanned and added to the FDT. For the SR-IOV case, default DMA window "ibm,dma-window" is removed from the FDT and DDW added, for the device. Now, kexec hands over control to the kdump kernel. When the kdump kernel initializes, PCI busses are scanned and IOMMU group/tables created, in pci_dma_bus_setup_pSeriesLP(). For the SR-IOV case, there is no "ibm,dma-window". The original commit: b1fc44e, fixes the path where memory is pre-mapped (direct mapped) to the DDW. When TCEs are direct mapped, there is no need to initialize IOMMU tables. iommu_table_setparms_lpar() only considers "ibm,dma-window" property when initiallizing IOMMU table. In the scenario where TCEs are dynamically allocated for SR-IOV, newly created IOMMU table is not initialized. Later, when the device driver tries to enter TCEs for the SR-IOV device, NULL pointer execption is thrown from iommu_area_alloc(). The fix is to initialize the IOMMU table with DDW property stored in the FDT. There are 2 points to remember: 1. For the dedicated adapter, kdump kernel would encounter both default and DDW in FDT. In this case, DDW property is used to initialize the IOMMU table. 2. A DDW could be direct or dynamic mapped. kdump kernel would initialize IOMMU table and mark the existing DDW as "dynamic". This works fine since, at the time of table initialization, iommu_table_clear() makes some space in the DDW, for some predefined number of TCEs which are needed for kdump to succeed. Fixes: b1fc44e ("pseries/iommu/ddw: Fix kdump to work in absence of ibm,dma-window") Signed-off-by: Gaurav Batra <[email protected]> Reviewed-by: Brian King <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://msgid.link/[email protected]

…SR-IOV [ Upstream commit 09a3c1e ] When kdump kernel tries to copy dump data over SR-IOV, LPAR panics due to NULL pointer exception: Kernel attempted to read user page (0) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on read at 0x00000000 Faulting instruction address: 0xc000000020847ad4 Oops: Kernel access of bad area, sig: 11 [gregkh#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries Modules linked in: mlx5_core(+) vmx_crypto pseries_wdt papr_scm libnvdimm mlxfw tls psample sunrpc fuse overlay squashfs loop CPU: 12 PID: 315 Comm: systemd-udevd Not tainted 6.4.0-Test102+ gregkh#12 Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_008) hv:phyp pSeries NIP: c000000020847ad4 LR: c00000002083b2dc CTR: 00000000006cd18c REGS: c000000029162ca0 TRAP: 0300 Not tainted (6.4.0-Test102+) MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 48288244 XER: 00000008 CFAR: c00000002083b2d8 DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 1 ... NIP _find_next_zero_bit+0x24/0x110 LR bitmap_find_next_zero_area_off+0x5c/0xe0 Call Trace: dev_printk_emit+0x38/0x48 (unreliable) iommu_area_alloc+0xc4/0x180 iommu_range_alloc+0x1e8/0x580 iommu_alloc+0x60/0x130 iommu_alloc_coherent+0x158/0x2b0 dma_iommu_alloc_coherent+0x3c/0x50 dma_alloc_attrs+0x170/0x1f0 mlx5_cmd_init+0xc0/0x760 [mlx5_core] mlx5_function_setup+0xf0/0x510 [mlx5_core] mlx5_init_one+0x84/0x210 [mlx5_core] probe_one+0x118/0x2c0 [mlx5_core] local_pci_probe+0x68/0x110 pci_call_probe+0x68/0x200 pci_device_probe+0xbc/0x1a0 really_probe+0x104/0x540 __driver_probe_device+0xb4/0x230 driver_probe_device+0x54/0x130 __driver_attach+0x158/0x2b0 bus_for_each_dev+0xa8/0x130 driver_attach+0x34/0x50 bus_add_driver+0x16c/0x300 driver_register+0xa4/0x1b0 __pci_register_driver+0x68/0x80 mlx5_init+0xb8/0x100 [mlx5_core] do_one_initcall+0x60/0x300 do_init_module+0x7c/0x2b0 At the time of LPAR dump, before kexec hands over control to kdump kernel, DDWs (Dynamic DMA Windows) are scanned and added to the FDT. For the SR-IOV case, default DMA window "ibm,dma-window" is removed from the FDT and DDW added, for the device. Now, kexec hands over control to the kdump kernel. When the kdump kernel initializes, PCI busses are scanned and IOMMU group/tables created, in pci_dma_bus_setup_pSeriesLP(). For the SR-IOV case, there is no "ibm,dma-window". The original commit: b1fc44e, fixes the path where memory is pre-mapped (direct mapped) to the DDW. When TCEs are direct mapped, there is no need to initialize IOMMU tables. iommu_table_setparms_lpar() only considers "ibm,dma-window" property when initiallizing IOMMU table. In the scenario where TCEs are dynamically allocated for SR-IOV, newly created IOMMU table is not initialized. Later, when the device driver tries to enter TCEs for the SR-IOV device, NULL pointer execption is thrown from iommu_area_alloc(). The fix is to initialize the IOMMU table with DDW property stored in the FDT. There are 2 points to remember: 1. For the dedicated adapter, kdump kernel would encounter both default and DDW in FDT. In this case, DDW property is used to initialize the IOMMU table. 2. A DDW could be direct or dynamic mapped. kdump kernel would initialize IOMMU table and mark the existing DDW as "dynamic". This works fine since, at the time of table initialization, iommu_table_clear() makes some space in the DDW, for some predefined number of TCEs which are needed for kdump to succeed. Fixes: b1fc44e ("pseries/iommu/ddw: Fix kdump to work in absence of ibm,dma-window") Signed-off-by: Gaurav Batra <[email protected]> Reviewed-by: Brian King <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://msgid.link/[email protected] Signed-off-by: Sasha Levin <[email protected]>

…-maps' Eduard Zingerman says: ==================== libbpf: type suffixes and autocreate flag for struct_ops maps Tweak struct_ops related APIs to allow the following features: - specify version suffixes for stuct_ops map types; - share same BPF program between several map definitions with different local BTF types, assuming only maps with same kernel BTF type would be selected for load; - toggle autocreate flag for struct_ops maps; - automatically toggle autoload for struct_ops programs referenced from struct_ops maps, depending on autocreate status of the corresponding map; - use SEC("?.struct_ops") and SEC("?.struct_ops.link") to define struct_ops maps with autocreate == false after object open. This would allow loading programs like below: SEC("struct_ops/foo") int BPF_PROG(foo) { ... } SEC("struct_ops/bar") int BPF_PROG(bar) { ... } struct bpf_testmod_ops___v1 { int (*foo)(void); }; struct bpf_testmod_ops___v2 { int (*foo)(void); int (*bar)(void); }; /* Assume kernel type name to be 'test_ops' */ SEC(".struct_ops.link") struct test_ops___v1 map_v1 = { /* Program 'foo' shared by maps with * different local BTF type */ .foo = (void *)foo }; SEC(".struct_ops.link") struct test_ops___v2 map_v2 = { .foo = (void *)foo, .bar = (void *)bar }; Assuming the following tweaks are done before loading: /* to load v1 */ bpf_map__set_autocreate(skel->maps.map_v1, true); bpf_map__set_autocreate(skel->maps.map_v2, false); /* to load v2 */ bpf_map__set_autocreate(skel->maps.map_v1, false); bpf_map__set_autocreate(skel->maps.map_v2, true); Patch gregkh#8 ties autocreate and autoload flags for struct_ops maps and programs. Changelog: - v3 [3] -> v4: - changes for multiple styling suggestions from Andrii; - patch amazonlinux#5: libbpf log capture now happens for LIBBPF_INFO and LIBBPF_WARN messages and does not depend on verbosity flags (Andrii); - patch gregkh#6: fixed runtime crash caused by conflict with newly added test case struct_ops_multi_pages; - patch gregkh#7: fixed free of possibly uninitialized pointer (Daniel) - patch gregkh#8: simpler algorithm to detect which programs to autoload (Andrii); - patch gregkh#9: added assertions for autoload flag after object load (Andrii); - patch gregkh#12: DATASEC name rewrite in libbpf is now done inplace, no new strings added to BTF (Andrii); - patch gregkh#14: allow any printable characters in DATASEC names when kernel validates BTF (Andrii) - v2 [2] -> v3: - moved patch gregkh#8 logic to be fully done on load (requested by Andrii in offlist discussion); - in patch gregkh#9 added test case for shadow vars and autocreate/autoload interaction. - v1 [1] -> v2: - fixed memory leak in patch amazonlinux#1 (Kui-Feng); - improved error messages in patch amazonlinux#2 (Martin, Andrii); - in bad_struct_ops selftest from patch gregkh#6 added .test_2 map member setup (David); - added utility functions to capture libbpf log from selftests (David) - in selftests replaced usage of ...__open_and_load by separate calls to ..._open() and ..._load() (Andrii); - removed serial_... in selftest definitions (Andrii); - improved comments in selftest struct_ops_autocreate from patch gregkh#7 (David); - removed autoload toggling logic incompatible with shadow variables from bpf_map__set_autocreate(), instead struct_ops programs autoload property is computed at struct_ops maps load phase, see patch gregkh#8 (Kui-Feng, Martin, Andrii); - added support for SEC("?.struct_ops") and SEC("?.struct_ops.link") (Andrii). [1] https://lore.kernel.org/bpf/[email protected]/ [2] https://lore.kernel.org/bpf/[email protected]/ [3] https://lore.kernel.org/bpf/[email protected]/ ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Andrii Nakryiko <[email protected]>

With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To thwart invalid memory accesses, the JITs add an exception table entry for all such accesses. But in case the src_reg + offset overflows and turns into a userspace address, the BPF program might read that memory if the user has mapped it. There are architectural features that prevent the kernel from accessing userspace memory, like Privileged Access Never (PAN) on ARM64, Supervisor Mode Access Prevention (SMAP) on x86-64, Supervisor User Memory access (SUM) on RISC-V, etc. but BPF should not rely on the existence of these features. Make the verifier add guard instructions before such memory accesses and skip the load if the address falls into the userspace region. The JITs need to implement bpf_arch_uaddress_limit() to define where the userspace addresses end for that architecture or TASK_SIZE is taken as default. The implementation is as follows: REG_AX = SRC_REG if(offset) REG_AX += offset; REG_AX >>= 32; if (REG_AX <= (uaddress_limit >> 32)) DST_REG = 0; else DST_REG = *(size *)(SRC_REG + offset); As we are comparing the upper 32 bits of load address with the upper 32 bits of uaddress_limit, we will be rejecting uaddress_limit + 4GB. In theory, both load address and uaddress_limit are being aligned down to a 4GB boundary and then the load is rejected if the (4GB aligned)load address <= (4GB aligned)uaddress_limit The above means that loads till uaddress_limit + 4GB are unintentionally rejected. This is acceptable because there is a large hole (much larger than 4GB) between userspace and kernel space memory => Correctly working BPF programs should anyway not access this 4GB memory above the userspace. Let's analyze what this patch does to the following fentry program dereferencing an untrusted pointer: SEC("fentry/tcp_v4_connect") int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk) { *(volatile long *)sk; return 0; } BPF Program before | BPF Program after ------------------ | ----------------- 0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0) ----------------------------------------------------------------------- 1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1 ----------------------------\ \ 2: (77) r11 >>= 32 2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2 3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0) \ 5: (05) goto pc+1 \ 6: (b7) r1 = 0 \-------------------------------------- 7: (b7) r0 = 0 8: (95) exit As you can see from above, in the best case (off=0), 5 extra instructions are emitted. Now, we analyse the same program after it has gone through the JITs of X86-64, ARM64, and RISC-V architectures. We follow the single load instruction that has the untrusted pointer and see what instrumentation has been added around it. x86-64 JIT ========== JIT's Instrumentation Verifier's Instrumentation (upstream) (This patch) --------------------- -------------------------- 0: nopl 0x0(%rax,%rax,1) 0: nopl 0x0(%rax,%rax,1) 5: xchg %ax,%ax 5: xchg %ax,%ax 7: push %rbp 7: push %rbp 8: mov %rsp,%rbp 8: mov %rsp,%rbp b: mov 0x0(%rdi),%rdi b: mov 0x0(%rdi),%rdi ------------------------------------------------------------------------ f: movabs $0x800000000000,%r11 f: mov %rdi,%r10 19: cmp %r11,%rdi 12: shr $0x20,%r10 1c: jb 0x000000000000002a 16: cmp $0x8000,%r10 1e: mov %rdi,%r11 1d: jbe 0x0000000000000025 21: add $0x0,%r11 /--> 1f: mov 0x0(%rdi),%rdi 28: jae 0x000000000000002e / 23: jmp 0x0000000000000027 2a: xor %edi,%edi / 25: xor %edi,%edi 2c: jmp 0x0000000000000032 / /------------------------------------ 2e: mov 0x0(%rdi),%rdi ---/ / 27: xor %eax,%eax ---------------------------------/ 29: leave 32: xor %eax,%eax 2a: ret 34: leave 35: ret The x86-64 JIT already emits some instructions to protect against user memory access. The implementation in this patch leads to a smaller number of instructions being emitted. In the worst case the JIT will emit 9 extra instructions and this patch decreases it to 7 (22.2% less). ARM64 JIT ========= No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: add x9, x30, #0x0 0: add x9, x30, #0x0 4: nop 4: nop 8: paciasp 8: paciasp c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]! 10: mov x29, sp 10: mov x29, sp 14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 24: mov x25, sp 24: mov x25, sp 28: mov x26, #0x0 28: mov x26, #0x0 2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0 30: sub sp, sp, #0x0 30: sub sp, sp, #0x0 34: ldr x0, [x0] 34: ldr x0, [x0] -------------------------------------------------------------------------------- 38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0 -----------------------------------\\ 3c: lsr x9, x9, #32 3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl gregkh#12 40: mov sp, sp \\ 44: b.ls 0x0000000000000050 44: ldp x27, x28, [sp], gregkh#16 \\--> 48: ldr x0, [x0] 48: ldp x25, x26, [sp], gregkh#16 \ 4c: b 0x0000000000000054 4c: ldp x21, x22, [sp], gregkh#16 \ 50: mov x0, #0x0 50: ldp x19, x20, [sp], gregkh#16 \--------------------------------------- 54: ldp x29, x30, [sp], gregkh#16 54: mov x7, #0x0 58: add x0, x7, #0x0 58: mov sp, sp 5c: autiasp 5c: ldp x27, x28, [sp], gregkh#16 60: ret 60: ldp x25, x26, [sp], gregkh#16 64: nop 64: ldp x21, x22, [sp], gregkh#16 68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], gregkh#16 6c: br x10 6c: ldp x29, x30, [sp], gregkh#16 70: add x0, x7, #0x0 74: autiasp 78: ret 7c: nop 80: ldr x10, 0x0000000000000088 84: br x10 There are 6 extra instructions added in ARM64 in the best case. This will become 7 in the worst case (off != 0). RISC-V JIT (RISCV_ISA_C Disabled) ========== No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: nop 0: nop 4: nop 4: nop 8: li a6, 33 8: li a6, 33 c: addi sp, sp, -16 c: addi sp, sp, -16 10: sd s0, 8(sp) 10: sd s0, 8(sp) 14: addi s0, sp, 16 14: addi s0, sp, 16 18: ld a0, 0(a0) 18: ld a0, 0(a0) --------------------------------------------------------------- 1c: ld a0, 0(a0) --\ 1c: mv t0, a0 --------------------------\ \ 20: srli t0, t0, 32 20: li a5, 0 \ \ 24: lui t1, 4096 24: ld s0, 8(sp) \ \ 28: sext.w t1, t1 28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12 2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0) 30: ret \ 34: j 8 \ 38: li a0, 0 \------------------------------ 3c: li a5, 0 40: ld s0, 8(sp) 44: addi sp, sp, 16 48: sext.w a0, a5 4c: ret There are 7 extra instructions added in RISC-V. Suggested-by: Alexei Starovoitov <[email protected]> Signed-off-by: Puranjay Mohan <[email protected]>

With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To thwart invalid memory accesses, the JITs add an exception table entry for all such accesses. But in case the src_reg + offset overflows and turns into a userspace address, the BPF program might read that memory if the user has mapped it. There are architectural features that prevent the kernel from accessing userspace memory, like Privileged Access Never (PAN) on ARM64, Supervisor Mode Access Prevention (SMAP) on x86-64, Supervisor User Memory access (SUM) on RISC-V, etc. But BPF should not rely on the existence of these features. Make the verifier add guard instructions around such memory accesses and skip the load if the address falls into the userspace region. The JITs need to implement bpf_arch_uaddress_limit() to define where the userspace addresses end for that architecture or TASK_SIZE is taken as default. The implementation is as follows: REG_AX = SRC_REG if(offset) REG_AX += offset; REG_AX >>= 32; if (REG_AX <= (uaddress_limit >> 32)) DST_REG = 0; else DST_REG = *(size *)(SRC_REG + offset); Comparing just the upper 32 bits of the load address with the upper 32 bits of uaddress_limit implies that the values are being aligned down to a 4GB boundary before comparison. The above means that all loads with address <= uaddress_limit + 4GB are skipped. This is acceptable because there is a large hole (much larger than 4GB) between userspace and kernel space memory, therefore a correctly functioning BPF programs should not access this 4GB memory above the userspace. Let's analyze what this patch does to the following fentry program dereferencing an untrusted pointer: SEC("fentry/tcp_v4_connect") int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk) { *(volatile long *)sk; return 0; } BPF Program before | BPF Program after ------------------ | ----------------- 0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0) ----------------------------------------------------------------------- 1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1 ----------------------------\ \ 2: (77) r11 >>= 32 2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2 3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0) \ 5: (05) goto pc+1 \ 6: (b7) r1 = 0 \-------------------------------------- 7: (b7) r0 = 0 8: (95) exit As you can see from above, in the best case (off=0), 5 extra instructions are emitted. Now, we analyse the same program after it has gone through the JITs of X86-64, ARM64, and RISC-V architectures. We follow the single load instruction that has the untrusted pointer and see what instrumentation has been added around it. x86-64 JIT ========== JIT's Instrumentation Verifier's Instrumentation (upstream) (This patch) --------------------- -------------------------- 0: nopl 0x0(%rax,%rax,1) 0: nopl 0x0(%rax,%rax,1) 5: xchg %ax,%ax 5: xchg %ax,%ax 7: push %rbp 7: push %rbp 8: mov %rsp,%rbp 8: mov %rsp,%rbp b: mov 0x0(%rdi),%rdi b: mov 0x0(%rdi),%rdi ------------------------------------------------------------------------ f: movabs $0x800000000000,%r11 f: mov %rdi,%r10 19: cmp %r11,%rdi 12: shr $0x20,%r10 1c: jb 0x000000000000002a 16: cmp $0x8000,%r10 1e: mov %rdi,%r11 1d: jbe 0x0000000000000025 21: add $0x0,%r11 /--> 1f: mov 0x0(%rdi),%rdi 28: jae 0x000000000000002e / 23: jmp 0x0000000000000027 2a: xor %edi,%edi / 25: xor %edi,%edi 2c: jmp 0x0000000000000032 / /------------------------------------ 2e: mov 0x0(%rdi),%rdi ---/ / 27: xor %eax,%eax ---------------------------------/ 29: leave 32: xor %eax,%eax 2a: ret 34: leave 35: ret The x86-64 JIT already emits some instructions to protect against user memory access. The implementation in this patch leads to a smaller number of instructions being emitted. In the worst case the JIT will emit 9 extra instructions and this patch decreases it to 7. ARM64 JIT ========= No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: add x9, x30, #0x0 0: add x9, x30, #0x0 4: nop 4: nop 8: paciasp 8: paciasp c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]! 10: mov x29, sp 10: mov x29, sp 14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 24: mov x25, sp 24: mov x25, sp 28: mov x26, #0x0 28: mov x26, #0x0 2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0 30: sub sp, sp, #0x0 30: sub sp, sp, #0x0 34: ldr x0, [x0] 34: ldr x0, [x0] -------------------------------------------------------------------------------- 38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0 -----------------------------------\\ 3c: lsr x9, x9, #32 3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl gregkh#12 40: mov sp, sp \\ 44: b.ls 0x0000000000000050 44: ldp x27, x28, [sp], gregkh#16 \\--> 48: ldr x0, [x0] 48: ldp x25, x26, [sp], gregkh#16 \ 4c: b 0x0000000000000054 4c: ldp x21, x22, [sp], gregkh#16 \ 50: mov x0, #0x0 50: ldp x19, x20, [sp], gregkh#16 \--------------------------------------- 54: ldp x29, x30, [sp], gregkh#16 54: mov x7, #0x0 58: add x0, x7, #0x0 58: mov sp, sp 5c: autiasp 5c: ldp x27, x28, [sp], gregkh#16 60: ret 60: ldp x25, x26, [sp], gregkh#16 64: nop 64: ldp x21, x22, [sp], gregkh#16 68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], gregkh#16 6c: br x10 6c: ldp x29, x30, [sp], gregkh#16 70: add x0, x7, #0x0 74: autiasp 78: ret 7c: nop 80: ldr x10, 0x0000000000000088 84: br x10 There are 6 extra instructions added in ARM64 in the best case. This will become 7 in the worst case (off != 0). RISC-V JIT (RISCV_ISA_C Disabled) ========== No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: nop 0: nop 4: nop 4: nop 8: li a6, 33 8: li a6, 33 c: addi sp, sp, -16 c: addi sp, sp, -16 10: sd s0, 8(sp) 10: sd s0, 8(sp) 14: addi s0, sp, 16 14: addi s0, sp, 16 18: ld a0, 0(a0) 18: ld a0, 0(a0) --------------------------------------------------------------- 1c: ld a0, 0(a0) --\ 1c: mv t0, a0 --------------------------\ \ 20: srli t0, t0, 32 20: li a5, 0 \ \ 24: lui t1, 4096 24: ld s0, 8(sp) \ \ 28: sext.w t1, t1 28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12 2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0) 30: ret \ 34: j 8 \ 38: li a0, 0 \------------------------------ 3c: li a5, 0 40: ld s0, 8(sp) 44: addi sp, sp, 16 48: sext.w a0, a5 4c: ret There are 7 extra instructions added in RISC-V. Fixes: 8008342 ("bpf, arm64: Add BPF exception tables") Reported-by: Breno Leitao <[email protected]> Suggested-by: Alexei Starovoitov <[email protected]> Signed-off-by: Puranjay Mohan <[email protected]>

With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To thwart invalid memory accesses, the JITs add an exception table entry for all such accesses. But in case the src_reg + offset overflows and turns into a userspace address, the BPF program might read that memory if the user has mapped it. There are architectural features that prevent the kernel from accessing userspace memory, like Privileged Access Never (PAN) on ARM64, Supervisor Mode Access Prevention (SMAP) on x86-64, Supervisor User Memory access (SUM) on RISC-V, etc. But BPF should not rely on the existence of these features. Make the verifier add guard instructions around such memory accesses and skip the load if the address falls into the userspace region. The JITs need to implement bpf_arch_uaddress_limit() to define where the userspace addresses end for that architecture or TASK_SIZE is taken as default. The implementation is as follows: REG_AX = SRC_REG if(offset) REG_AX += offset; REG_AX >>= 32; if (REG_AX <= (uaddress_limit >> 32)) DST_REG = 0; else DST_REG = *(size *)(SRC_REG + offset); Comparing just the upper 32 bits of the load address with the upper 32 bits of uaddress_limit implies that the values are being aligned down to a 4GB boundary before comparison. The above means that all loads with address <= uaddress_limit + 4GB are skipped. This is acceptable because there is a large hole (much larger than 4GB) between userspace and kernel space memory, therefore a correctly functioning BPF program should not access this 4GB memory above the userspace. Let's analyze what this patch does to the following fentry program dereferencing an untrusted pointer: SEC("fentry/tcp_v4_connect") int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk) { *(volatile long *)sk; return 0; } BPF Program before | BPF Program after ------------------ | ----------------- 0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0) ----------------------------------------------------------------------- 1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1 ----------------------------\ \ 2: (77) r11 >>= 32 2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2 3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0) \ 5: (05) goto pc+1 \ 6: (b7) r1 = 0 \-------------------------------------- 7: (b7) r0 = 0 8: (95) exit As you can see from above, in the best case (off=0), 5 extra instructions are emitted. Now, we analyse the same program after it has gone through the JITs of X86-64, ARM64, and RISC-V architectures. We follow the single load instruction that has the untrusted pointer and see what instrumentation has been added around it. x86-64 JIT ========== JIT's Instrumentation Verifier's Instrumentation (upstream) (This patch) --------------------- -------------------------- 0: nopl 0x0(%rax,%rax,1) 0: nopl 0x0(%rax,%rax,1) 5: xchg %ax,%ax 5: xchg %ax,%ax 7: push %rbp 7: push %rbp 8: mov %rsp,%rbp 8: mov %rsp,%rbp b: mov 0x0(%rdi),%rdi b: mov 0x0(%rdi),%rdi ------------------------------------------------------------------------ f: movabs $0x800000000000,%r11 f: mov %rdi,%r10 19: cmp %r11,%rdi 12: shr $0x20,%r10 1c: jb 0x000000000000002a 16: cmp $0x8000,%r10 1e: mov %rdi,%r11 1d: jbe 0x0000000000000025 21: add $0x0,%r11 /--> 1f: mov 0x0(%rdi),%rdi 28: jae 0x000000000000002e / 23: jmp 0x0000000000000027 2a: xor %edi,%edi / 25: xor %edi,%edi 2c: jmp 0x0000000000000032 / /------------------------------------ 2e: mov 0x0(%rdi),%rdi ---/ / 27: xor %eax,%eax ---------------------------------/ 29: leave 32: xor %eax,%eax 2a: ret 34: leave 35: ret The x86-64 JIT already emits some instructions to protect against user memory access. The implementation in this patch leads to a smaller number of instructions being emitted. In the worst case the JIT will emit 9 extra instructions and this patch decreases it to 7. ARM64 JIT ========= No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: add x9, x30, #0x0 0: add x9, x30, #0x0 4: nop 4: nop 8: paciasp 8: paciasp c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]! 10: mov x29, sp 10: mov x29, sp 14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 24: mov x25, sp 24: mov x25, sp 28: mov x26, #0x0 28: mov x26, #0x0 2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0 30: sub sp, sp, #0x0 30: sub sp, sp, #0x0 34: ldr x0, [x0] 34: ldr x0, [x0] -------------------------------------------------------------------------------- 38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0 -----------------------------------\\ 3c: lsr x9, x9, #32 3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl gregkh#12 40: mov sp, sp \\ 44: b.ls 0x0000000000000050 44: ldp x27, x28, [sp], gregkh#16 \\--> 48: ldr x0, [x0] 48: ldp x25, x26, [sp], gregkh#16 \ 4c: b 0x0000000000000054 4c: ldp x21, x22, [sp], gregkh#16 \ 50: mov x0, #0x0 50: ldp x19, x20, [sp], gregkh#16 \--------------------------------------- 54: ldp x29, x30, [sp], gregkh#16 54: mov x7, #0x0 58: add x0, x7, #0x0 58: mov sp, sp 5c: autiasp 5c: ldp x27, x28, [sp], gregkh#16 60: ret 60: ldp x25, x26, [sp], gregkh#16 64: nop 64: ldp x21, x22, [sp], gregkh#16 68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], gregkh#16 6c: br x10 6c: ldp x29, x30, [sp], gregkh#16 70: add x0, x7, #0x0 74: autiasp 78: ret 7c: nop 80: ldr x10, 0x0000000000000088 84: br x10 There are 6 extra instructions added in ARM64 in the best case. This will become 7 in the worst case (off != 0). RISC-V JIT (RISCV_ISA_C Disabled) ========== No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: nop 0: nop 4: nop 4: nop 8: li a6, 33 8: li a6, 33 c: addi sp, sp, -16 c: addi sp, sp, -16 10: sd s0, 8(sp) 10: sd s0, 8(sp) 14: addi s0, sp, 16 14: addi s0, sp, 16 18: ld a0, 0(a0) 18: ld a0, 0(a0) --------------------------------------------------------------- 1c: ld a0, 0(a0) --\ 1c: mv t0, a0 --------------------------\ \ 20: srli t0, t0, 32 20: li a5, 0 \ \ 24: lui t1, 4096 24: ld s0, 8(sp) \ \ 28: sext.w t1, t1 28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12 2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0) 30: ret \ 34: j 8 \ 38: li a0, 0 \------------------------------ 3c: li a5, 0 40: ld s0, 8(sp) 44: addi sp, sp, 16 48: sext.w a0, a5 4c: ret There are 7 extra instructions added in RISC-V. Fixes: 8008342 ("bpf, arm64: Add BPF exception tables") Reported-by: Breno Leitao <[email protected]> Suggested-by: Alexei Starovoitov <[email protected]> Signed-off-by: Puranjay Mohan <[email protected]>

Petr Machata says: ==================== selftests: Fixes for kernel CI As discussed on the bi-weekly call on Jan 30, and in mailing around kernel CI effort, some changes are desirable in the suite of forwarding selftests the better to work with the CI tooling. Namely: - The forwarding selftests use a configuration file where names of interfaces are defined and various variables can be overridden. There is also forwarding.config.sample that users can use as a template to refer to when creating the config file. What happens a fair bit is that users either do not know about this at all, or simply forget, and are confused by cryptic failures about interfaces that cannot be created. In patches amazonlinux#1 - amazonlinux#3 have lib.sh just be the single source of truth with regards to which variables exist. That includes the topology variables which were previously only in the sample file, and any "tweak variables", such as what tools to use, sleep times, etc. forwarding.config.sample then becomes just a placeholder with a couple examples. Unless specific HW should be exercised, or specific tools used, the defaults are usually just fine. - Several net/forwarding/ selftests (and one net/ one) cannot be run on veth pairs, they need an actual HW interface to run on. They are generic in the sense that any capable HW should pass them, which is why they have been put to net/forwarding/ as opposed to drivers/net/, but they do not generalize to veth. The fact that these tests are in net/forwarding/, but still complaining when run, is confusing. In patches amazonlinux#4 - gregkh#6 move these tests to a new directory drivers/net/hw. - The following patches extend the codebase to handle well test results other than pass and fail. Patch gregkh#7 is preparatory. It converts several log_test_skip to XFAIL, so that tests do not spuriously end up returning non-0 when they are not supposed to. In patches gregkh#8 - gregkh#10, introduce some missing ksft constants, then support having those constants in RET, and then finally in EXIT_STATUS. - The traffic scheduler tests generate a large amount of network traffic to test the behavior of the scheduler. This demands a relatively high-performance computer. On slow machines, such as with a debugging kernel, the test would spuriously fail. It can still be useful to "go through the motions" though, to possibly catch bugs in setup of the scheduler graph and passing packets around. Thus we still want to run the tests, just with lowered demands. To that end, in patches gregkh#11 - gregkh#12, introduce an environment variable KSFT_MACHINE_SLOW, with obvious meaning. Tests can then make checks more lenient, such as mark failures as XFAIL. A helper, xfail_on_slow, is provided to mark performance-sensitive parts of the selftest. - In patch gregkh#13, use a similar mechanism to mark a NH group stats selftest to XFAIL HW stats tests when run on VETH pairs. - All these changes complicate the hitherto straightforward logging and checking logic, so in patch gregkh#14, add a selftest that checks this functionality in lib.sh. v1 (vs. an RFC circulated through linux-kselftest): - Patch gregkh#9: - Clarify intended usage by s/set_ret/ret_set_ksft_status/, s/nret/ksft_status/ ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

vhost_worker will call tun call backs to receive packets. If too many illegal packets arrives, tun_do_read will keep dumping packet contents. When console is enabled, it will costs much more cpu time to dump packet and soft lockup will be detected. net_ratelimit mechanism can be used to limit the dumping rate. PID: 33036 TASK: ffff949da6f20000 CPU: 23 COMMAND: "vhost-32980" #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253 gregkh#1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3 gregkh#2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e gregkh#3 [fffffe00003fced0] do_nmi at ffffffff8922660d gregkh#4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663 [exception RIP: io_serial_in+20] RIP: ffffffff89792594 RSP: ffffa655314979e8 RFLAGS: 00000002 RAX: ffffffff89792500 RBX: ffffffff8af428a0 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff8af428a0 RBP: 0000000000002710 R8: 0000000000000004 R9: 000000000000000f R10: 0000000000000000 R11: ffffffff8acbf64f R12: 0000000000000020 R13: ffffffff8acbf698 R14: 0000000000000058 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 gregkh#5 [ffffa655314979e8] io_serial_in at ffffffff89792594 gregkh#6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470 gregkh#7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6 gregkh#8 [ffffa65531497a20] uart_console_write at ffffffff8978b605 gregkh#9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558 gregkh#10 [ffffa65531497ac8] console_unlock at ffffffff89316124 gregkh#11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07 gregkh#12 [ffffa65531497b68] printk at ffffffff89318306 gregkh#13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765 gregkh#14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun] gregkh#15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun] gregkh#16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net] gregkh#17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost] gregkh#18 [ffffa65531497f10] kthread at ffffffff892d2e72 gregkh#19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors") Signed-off-by: Lei Chen <[email protected]> Reviewed-by: Willem de Bruijn <[email protected]> Acked-by: Jason Wang <[email protected]> Reviewed-by: Eric Dumazet <[email protected]> Acked-by: Michael S. Tsirkin <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

Here is the first fix for gregkh#12, which fix the limited cpufreq for schedutil. But it still tend to stay at max cpufreq.

With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To thwart invalid memory accesses, the JITs add an exception table entry for all such accesses. But in case the src_reg + offset overflows and turns into a userspace address, the BPF program might read that memory if the user has mapped it. There are architectural features that prevent the kernel from accessing userspace memory, like Privileged Access Never (PAN) on ARM64, Supervisor Mode Access Prevention (SMAP) on x86-64, Supervisor User Memory access (SUM) on RISC-V, etc. But BPF should not rely on the existence of these features. Make the verifier add guard instructions around such memory accesses and skip the load if the address falls into the userspace region. The JITs need to implement bpf_arch_uaddress_limit() to define where the userspace addresses end for that architecture or TASK_SIZE is taken as default. The implementation is as follows: REG_AX = SRC_REG if(offset) REG_AX += offset; REG_AX >>= 32; if (REG_AX <= (uaddress_limit >> 32)) DST_REG = 0; else DST_REG = *(size *)(SRC_REG + offset); Comparing just the upper 32 bits of the load address with the upper 32 bits of uaddress_limit implies that the values are being aligned down to a 4GB boundary before comparison. The above means that all loads with address <= uaddress_limit + 4GB are skipped. This is acceptable because there is a large hole (much larger than 4GB) between userspace and kernel space memory, therefore a correctly functioning BPF program should not access this 4GB memory above the userspace. Let's analyze what this patch does to the following fentry program dereferencing an untrusted pointer: SEC("fentry/tcp_v4_connect") int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk) { *(volatile long *)sk; return 0; } BPF Program before | BPF Program after ------------------ | ----------------- 0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0) ----------------------------------------------------------------------- 1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1 ----------------------------\ \ 2: (77) r11 >>= 32 2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2 3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0) \ 5: (05) goto pc+1 \ 6: (b7) r1 = 0 \-------------------------------------- 7: (b7) r0 = 0 8: (95) exit As you can see from above, in the best case (off=0), 5 extra instructions are emitted. Now, we analyse the same program after it has gone through the JITs of ARM64 and RISC-V architectures. We follow the single load instruction that has the untrusted pointer and see what instrumentation has been added around it. x86-64 JIT ========== JIT's Instrumentation (upstream) --------------------- 0: nopl 0x0(%rax,%rax,1) 5: xchg %ax,%ax 7: push %rbp 8: mov %rsp,%rbp b: mov 0x0(%rdi),%rdi --------------------------------- f: movabs $0x800000000000,%r11 19: cmp %r11,%rdi 1c: jb 0x000000000000002a 1e: mov %rdi,%r11 21: add $0x0,%r11 28: jae 0x000000000000002e 2a: xor %edi,%edi 2c: jmp 0x0000000000000032 2e: mov 0x0(%rdi),%rdi ---/ --------------------------------- 32: xor %eax,%eax 34: leave 35: ret The x86-64 JIT already emits some instructions to protect against user memory access. This patch doesn't make any changes for the x86-64 architecture. ARM64 JIT ========= No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: add x9, x30, #0x0 0: add x9, x30, #0x0 4: nop 4: nop 8: paciasp 8: paciasp c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]! 10: mov x29, sp 10: mov x29, sp 14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]! 24: mov x25, sp 24: mov x25, sp 28: mov x26, #0x0 28: mov x26, #0x0 2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0 30: sub sp, sp, #0x0 30: sub sp, sp, #0x0 34: ldr x0, [x0] 34: ldr x0, [x0] -------------------------------------------------------------------------------- 38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0 -----------------------------------\\ 3c: lsr x9, x9, #32 3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl gregkh#12 40: mov sp, sp \\ 44: b.ls 0x0000000000000050 44: ldp x27, x28, [sp], gregkh#16 \\--> 48: ldr x0, [x0] 48: ldp x25, x26, [sp], gregkh#16 \ 4c: b 0x0000000000000054 4c: ldp x21, x22, [sp], gregkh#16 \ 50: mov x0, #0x0 50: ldp x19, x20, [sp], gregkh#16 \--------------------------------------- 54: ldp x29, x30, [sp], gregkh#16 54: mov x7, #0x0 58: add x0, x7, #0x0 58: mov sp, sp 5c: autiasp 5c: ldp x27, x28, [sp], gregkh#16 60: ret 60: ldp x25, x26, [sp], gregkh#16 64: nop 64: ldp x21, x22, [sp], gregkh#16 68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], gregkh#16 6c: br x10 6c: ldp x29, x30, [sp], gregkh#16 70: add x0, x7, #0x0 74: autiasp 78: ret 7c: nop 80: ldr x10, 0x0000000000000088 84: br x10 There are 6 extra instructions added in ARM64 in the best case. This will become 7 in the worst case (off != 0). RISC-V JIT (RISCV_ISA_C Disabled) ========== No Intrumentation Verifier's Instrumentation (upstream) (This patch) ----------------- -------------------------- 0: nop 0: nop 4: nop 4: nop 8: li a6, 33 8: li a6, 33 c: addi sp, sp, -16 c: addi sp, sp, -16 10: sd s0, 8(sp) 10: sd s0, 8(sp) 14: addi s0, sp, 16 14: addi s0, sp, 16 18: ld a0, 0(a0) 18: ld a0, 0(a0) --------------------------------------------------------------- 1c: ld a0, 0(a0) --\ 1c: mv t0, a0 --------------------------\ \ 20: srli t0, t0, 32 20: li a5, 0 \ \ 24: lui t1, 4096 24: ld s0, 8(sp) \ \ 28: sext.w t1, t1 28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12 2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0) 30: ret \ 34: j 8 \ 38: li a0, 0 \------------------------------ 3c: li a5, 0 40: ld s0, 8(sp) 44: addi sp, sp, 16 48: sext.w a0, a5 4c: ret There are 7 extra instructions added in RISC-V. Fixes: 8008342 ("bpf, arm64: Add BPF exception tables") Reported-by: Breno Leitao <[email protected]> Suggested-by: Alexei Starovoitov <[email protected]> Acked-by: Ilya Leoshkevich <[email protected]> Signed-off-by: Puranjay Mohan <[email protected]>

Here is the first fix for gregkh#12, which fix the limited cpufreq for schedutil. But it still tend to stay at max cpufreq.

[ Upstream commit f8bbc07 ] vhost_worker will call tun call backs to receive packets. If too many illegal packets arrives, tun_do_read will keep dumping packet contents. When console is enabled, it will costs much more cpu time to dump packet and soft lockup will be detected. net_ratelimit mechanism can be used to limit the dumping rate. PID: 33036 TASK: ffff949da6f20000 CPU: 23 COMMAND: "vhost-32980" #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e #3 [fffffe00003fced0] do_nmi at ffffffff8922660d #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663 [exception RIP: io_serial_in+20] RIP: ffffffff89792594 RSP: ffffa655314979e8 RFLAGS: 00000002 RAX: ffffffff89792500 RBX: ffffffff8af428a0 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff8af428a0 RBP: 0000000000002710 R8: 0000000000000004 R9: 000000000000000f R10: 0000000000000000 R11: ffffffff8acbf64f R12: 0000000000000020 R13: ffffffff8acbf698 R14: 0000000000000058 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07 #12 [ffffa65531497b68] printk at ffffffff89318306 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun] #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun] #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net] #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost] #18 [ffffa65531497f10] kthread at ffffffff892d2e72 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors") Signed-off-by: Lei Chen <[email protected]> Reviewed-by: Willem de Bruijn <[email protected]> Acked-by: Jason Wang <[email protected]> Reviewed-by: Eric Dumazet <[email protected]> Acked-by: Michael S. Tsirkin <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit eedf3e3 ] ACPICA commit 1c28da2242783579d59767617121035dafba18c3 This was originally done in NetBSD: NetBSD/src@b69d1ac and is the correct alternative to the smattering of `memcpy`s I previously contributed to this repository. This also sidesteps the newly strict checks added in UBSAN: llvm/llvm-project@7926744 Before this change we see the following UBSAN stack trace in Fuchsia: #0 0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e #1.2 0x000021982bc4af3c in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x41f3c #1.1 0x000021982bc4af3c in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x41f3c #1 0x000021982bc4af3c in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:395 <libclang_rt.asan.so>+0x41f3c #2 0x000021982bc4bb6f in handletype_mismatch_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:137 <libclang_rt.asan.so>+0x42b6f #3 0x000021982bc4b723 in __ubsan_handle_type_mismatch_v1 compiler-rt/lib/ubsan/ubsan_handlers.cpp:142 <libclang_rt.asan.so>+0x42723 #4 0x000021afcfdeca5e in acpi_rs_get_address_common(struct acpi_resource*, union aml_resource*) ../../third_party/acpica/source/components/resources/rsaddr.c:329 <platform-bus-x86.so>+0x6aca5e #5 0x000021afcfdf2089 in acpi_rs_convert_aml_to_resource(struct acpi_resource*, union aml_resource*, struct acpi_rsconvert_info*) ../../third_party/acpica/source/components/resources/rsmisc.c:355 <platform-bus-x86.so>+0x6b2089 #6 0x000021afcfded169 in acpi_rs_convert_aml_to_resources(u8*, u32, u32, u8, void**) ../../third_party/acpica/source/components/resources/rslist.c:137 <platform-bus-x86.so>+0x6ad169 #7 0x000021afcfe2d24a in acpi_ut_walk_aml_resources(struct acpi_walk_state*, u8*, acpi_size, acpi_walk_aml_callback, void**) ../../third_party/acpica/source/components/utilities/utresrc.c:237 <platform-bus-x86.so>+0x6ed24a #8 0x000021afcfde66b7 in acpi_rs_create_resource_list(union acpi_operand_object*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rscreate.c:199 <platform-bus-x86.so>+0x6a66b7 #9 0x000021afcfdf6979 in acpi_rs_get_method_data(acpi_handle, const char*, struct acpi_buffer*) ../../third_party/acpica/source/components/resources/rsutils.c:770 <platform-bus-x86.so>+0x6b6979 #10 0x000021afcfdf708f in acpi_walk_resources(acpi_handle, char*, acpi_walk_resource_callback, void*) ../../third_party/acpica/source/components/resources/rsxface.c:731 <platform-bus-x86.so>+0x6b708f #11 0x000021afcfa95dcf in acpi::acpi_impl::walk_resources(acpi::acpi_impl*, acpi_handle, const char*, acpi::Acpi::resources_callable) ../../src/devices/board/lib/acpi/acpi-impl.cc:41 <platform-bus-x86.so>+0x355dcf #12 0x000021afcfaa8278 in acpi::device_builder::gather_resources(acpi::device_builder*, acpi::Acpi*, fidl::any_arena&, acpi::Manager*, acpi::device_builder::gather_resources_callback) ../../src/devices/board/lib/acpi/device-builder.cc:84 <platform-bus-x86.so>+0x368278 #13 0x000021afcfbddb87 in acpi::Manager::configure_discovered_devices(acpi::Manager*) ../../src/devices/board/lib/acpi/manager.cc:75 <platform-bus-x86.so>+0x49db87 #14 0x000021afcf99091d in publish_acpi_devices(acpi::Manager*, zx_device_t*, zx_device_t*) ../../src/devices/board/drivers/x86/acpi-nswalk.cc:95 <platform-bus-x86.so>+0x25091d #15 0x000021afcf9c1d4e in x86::X86::do_init(x86::X86*) ../../src/devices/board/drivers/x86/x86.cc:60 <platform-bus-x86.so>+0x281d4e #16 0x000021afcf9e33ad in λ(x86::X86::ddk_init::(anon class)*) ../../src/devices/board/drivers/x86/x86.cc:77 <platform-bus-x86.so>+0x2a33ad #17 0x000021afcf9e313e in fit::internal::target<(lambda at../../src/devices/board/drivers/x86/x86.cc:76:19), false, false, std::__2::allocator<std::byte>, void>::invoke(void*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:183 <platform-bus-x86.so>+0x2a313e #18 0x000021afcfbab4c7 in fit::internal::function_base<16UL, false, void(), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <platform-bus-x86.so>+0x46b4c7 #19 0x000021afcfbab342 in fit::function_impl<16UL, false, void(), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<16UL, false, void (), std::__2::allocator<std::byte> >*) ../../sdk/lib/fit/include/lib/fit/function.h:315 <platform-bus-x86.so>+0x46b342 #20 0x000021afcfcd98c3 in async::internal::retained_task::Handler(async_dispatcher_t*, async_task_t*, zx_status_t) ../../sdk/lib/async/task.cc:24 <platform-bus-x86.so>+0x5998c3 #21 0x00002290f9924616 in λ(const driver_runtime::Dispatcher::post_task::(anon class)*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/dispatcher.cc:789 <libdriver_runtime.so>+0x10a616 #22 0x00002290f9924323 in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:788:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int>::invoke(void*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0x10a323 #23 0x00002290f9904b76 in fit::internal::function_base<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xeab76 #24 0x00002290f9904831 in fit::callback_impl<24UL, true, void(std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request>>, int), std::__2::allocator<std::byte>>::operator()(fit::callback_impl<24UL, true, void (std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, int) ../../sdk/lib/fit/include/lib/fit/function.h:471 <libdriver_runtime.so>+0xea831 #25 0x00002290f98d5adc in driver_runtime::callback_request::Call(driver_runtime::callback_request*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >, zx_status_t) ../../src/devices/bin/driver_runtime/callback_request.h:74 <libdriver_runtime.so>+0xbbadc #26 0x00002290f98e1e58 in driver_runtime::Dispatcher::dispatch_callback(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::callback_request, std::__2::default_delete<driver_runtime::callback_request> >) ../../src/devices/bin/driver_runtime/dispatcher.cc:1248 <libdriver_runtime.so>+0xc7e58 #27 0x00002290f98e4159 in driver_runtime::Dispatcher::dispatch_callbacks(driver_runtime::Dispatcher*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:1308 <libdriver_runtime.so>+0xca159 #28 0x00002290f9918414 in λ(const driver_runtime::Dispatcher::create_with_adder::(anon class)*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.cc:353 <libdriver_runtime.so>+0xfe414 #29 0x00002290f991812d in fit::internal::target<(lambda at../../src/devices/bin/driver_runtime/dispatcher.cc:351:7), true, false, std::__2::allocator<std::byte>, void, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>>::invoke(void*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:128 <libdriver_runtime.so>+0xfe12d #30 0x00002290f9906fc7 in fit::internal::function_base<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::invoke(const fit::internal::function_base<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/internal/function.h:522 <libdriver_runtime.so>+0xecfc7 #31 0x00002290f9906c66 in fit::function_impl<8UL, true, void(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter>>, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte>>::operator()(const fit::function_impl<8UL, true, void (std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>), std::__2::allocator<std::byte> >*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../sdk/lib/fit/include/lib/fit/function.h:315 <libdriver_runtime.so>+0xecc66 #32 0x00002290f98e73d9 in driver_runtime::Dispatcher::event_waiter::invoke_callback(driver_runtime::Dispatcher::event_waiter*, std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, fbl::ref_ptr<driver_runtime::Dispatcher>) ../../src/devices/bin/driver_runtime/dispatcher.h:543 <libdriver_runtime.so>+0xcd3d9 #33 0x00002290f98e700d in driver_runtime::Dispatcher::event_waiter::handle_event(std::__2::unique_ptr<driver_runtime::Dispatcher::event_waiter, std::__2::default_delete<driver_runtime::Dispatcher::event_waiter> >, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/dispatcher.cc:1442 <libdriver_runtime.so>+0xcd00d #34 0x00002290f9918983 in async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event(async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>*, async_dispatcher_t*, async::wait_base*, zx_status_t, zx_packet_signal_t const*) ../../src/devices/bin/driver_runtime/async_loop_owned_event_handler.h:59 <libdriver_runtime.so>+0xfe983 #35 0x00002290f9918b9e in async::wait_method<async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>, &async_loop_owned_event_handler<driver_runtime::Dispatcher::event_waiter>::handle_event>::call_handler(async_dispatcher_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async/include/lib/async/cpp/wait.h:201 <libdriver_runtime.so>+0xfeb9e #36 0x00002290f99bf509 in async_loop_dispatch_wait(async_loop_t*, async_wait_t*, zx_status_t, zx_packet_signal_t const*) ../../sdk/lib/async-loop/loop.c:394 <libdriver_runtime.so>+0x1a5509 #37 0x00002290f99b9958 in async_loop_run_once(async_loop_t*, zx_time_t) ../../sdk/lib/async-loop/loop.c:343 <libdriver_runtime.so>+0x19f958 #38 0x00002290f99b9247 in async_loop_run(async_loop_t*, zx_time_t, _Bool) ../../sdk/lib/async-loop/loop.c:301 <libdriver_runtime.so>+0x19f247 #39 0x00002290f99ba962 in async_loop_run_thread(void*) ../../sdk/lib/async-loop/loop.c:860 <libdriver_runtime.so>+0x1a0962 #40 0x000041afd176ef30 in start_c11(void*) ../../zircon/third_party/ulib/musl/pthread/pthread_create.c:63 <libc.so>+0x84f30 #41 0x000041afd18a448d in thread_trampoline(uintptr_t, uintptr_t) ../../zircon/system/ulib/runtime/thread.cc:100 <libc.so>+0x1ba48d Link: acpica/acpica@1c28da22 Signed-off-by: Rafael J. Wysocki <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Tamir Duberstein <[email protected]> [ rjw: Pick up the tag from Tamir ] Signed-off-by: Rafael J. Wysocki <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

In probe appletb_kbd_probe() a "struct appletb_kbd *kbd" is allocated via devm_kzalloc() to store touch bar keyboard related data. Later on if backlight_device_get_by_name() finds a backlight device with name "appletb_backlight" a timer (kbd->inactivity_timer) is setup with appletb_inactivity_timer() and the timer is armed to run after appletb_tb_dim_timeout (60) seconds. A use-after-free is triggered when failure occurs after the timer is armed. This ultimately means probe failure occurs and as a result the "struct appletb_kbd *kbd" which is device managed memory is freed. After 60 seconds the timer will have expired and __run_timers will attempt to access the timer (kbd->inactivity_timer) however the kdb structure has been freed causing a use-after free. [ 71.636938] ================================================================== [ 71.637915] BUG: KASAN: slab-use-after-free in __run_timers+0x7ad/0x890 [ 71.637915] Write of size 8 at addr ffff8881178c5958 by task swapper/1/0 [ 71.637915] [ 71.637915] CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc2-00318-g739a6c93cc75-dirty gregkh#12 PREEMPT(voluntary) [ 71.637915] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 [ 71.637915] Call Trace: [ 71.637915] <IRQ> [ 71.637915] dump_stack_lvl+0x53/0x70 [ 71.637915] print_report+0xce/0x670 [ 71.637915] ? __run_timers+0x7ad/0x890 [ 71.637915] kasan_report+0xce/0x100 [ 71.637915] ? __run_timers+0x7ad/0x890 [ 71.637915] __run_timers+0x7ad/0x890 [ 71.637915] ? __pfx___run_timers+0x10/0x10 [ 71.637915] ? update_process_times+0xfc/0x190 [ 71.637915] ? __pfx_update_process_times+0x10/0x10 [ 71.637915] ? _raw_spin_lock_irq+0x80/0xe0 [ 71.637915] ? _raw_spin_lock_irq+0x80/0xe0 [ 71.637915] ? __pfx__raw_spin_lock_irq+0x10/0x10 [ 71.637915] run_timer_softirq+0x141/0x240 [ 71.637915] ? __pfx_run_timer_softirq+0x10/0x10 [ 71.637915] ? __pfx___hrtimer_run_queues+0x10/0x10 [ 71.637915] ? kvm_clock_get_cycles+0x18/0x30 [ 71.637915] ? ktime_get+0x60/0x140 [ 71.637915] handle_softirqs+0x1b8/0x5c0 [ 71.637915] ? __pfx_handle_softirqs+0x10/0x10 [ 71.637915] irq_exit_rcu+0xaf/0xe0 [ 71.637915] sysvec_apic_timer_interrupt+0x6c/0x80 [ 71.637915] </IRQ> [ 71.637915] [ 71.637915] Allocated by task 39: [ 71.637915] kasan_save_stack+0x33/0x60 [ 71.637915] kasan_save_track+0x14/0x30 [ 71.637915] __kasan_kmalloc+0x8f/0xa0 [ 71.637915] __kmalloc_node_track_caller_noprof+0x195/0x420 [ 71.637915] devm_kmalloc+0x74/0x1e0 [ 71.637915] appletb_kbd_probe+0x37/0x3c0 [ 71.637915] hid_device_probe+0x2d1/0x680 [ 71.637915] really_probe+0x1c3/0x690 [ 71.637915] __driver_probe_device+0x247/0x300 [ 71.637915] driver_probe_device+0x49/0x210 [...] [ 71.637915] [ 71.637915] Freed by task 39: [ 71.637915] kasan_save_stack+0x33/0x60 [ 71.637915] kasan_save_track+0x14/0x30 [ 71.637915] kasan_save_free_info+0x3b/0x60 [ 71.637915] __kasan_slab_free+0x37/0x50 [ 71.637915] kfree+0xcf/0x360 [ 71.637915] devres_release_group+0x1f8/0x3c0 [ 71.637915] hid_device_probe+0x315/0x680 [ 71.637915] really_probe+0x1c3/0x690 [ 71.637915] __driver_probe_device+0x247/0x300 [ 71.637915] driver_probe_device+0x49/0x210 [...] The root cause of the issue is that the timer is not disarmed on failure paths leading to it remaining active and accessing freed memory. To fix this call timer_delete_sync() to deactivate the timer. Another small issue is that timer_delete_sync is called unconditionally in appletb_kbd_remove(), fix this by checking for a valid kbd->backlight_dev before calling timer_delete_sync. Fixes: 93a0fc4 ("HID: hid-appletb-kbd: add support for automatic brightness control while using the touchbar") Cc: [email protected] Signed-off-by: Qasim Ijaz <[email protected]> Reviewed-by: Aditya Garg <[email protected]> Signed-off-by: Jiri Kosina <[email protected]>

commit 38224c4 upstream. In probe appletb_kbd_probe() a "struct appletb_kbd *kbd" is allocated via devm_kzalloc() to store touch bar keyboard related data. Later on if backlight_device_get_by_name() finds a backlight device with name "appletb_backlight" a timer (kbd->inactivity_timer) is setup with appletb_inactivity_timer() and the timer is armed to run after appletb_tb_dim_timeout (60) seconds. A use-after-free is triggered when failure occurs after the timer is armed. This ultimately means probe failure occurs and as a result the "struct appletb_kbd *kbd" which is device managed memory is freed. After 60 seconds the timer will have expired and __run_timers will attempt to access the timer (kbd->inactivity_timer) however the kdb structure has been freed causing a use-after free. [ 71.636938] ================================================================== [ 71.637915] BUG: KASAN: slab-use-after-free in __run_timers+0x7ad/0x890 [ 71.637915] Write of size 8 at addr ffff8881178c5958 by task swapper/1/0 [ 71.637915] [ 71.637915] CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc2-00318-g739a6c93cc75-dirty gregkh#12 PREEMPT(voluntary) [ 71.637915] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 [ 71.637915] Call Trace: [ 71.637915] <IRQ> [ 71.637915] dump_stack_lvl+0x53/0x70 [ 71.637915] print_report+0xce/0x670 [ 71.637915] ? __run_timers+0x7ad/0x890 [ 71.637915] kasan_report+0xce/0x100 [ 71.637915] ? __run_timers+0x7ad/0x890 [ 71.637915] __run_timers+0x7ad/0x890 [ 71.637915] ? __pfx___run_timers+0x10/0x10 [ 71.637915] ? update_process_times+0xfc/0x190 [ 71.637915] ? __pfx_update_process_times+0x10/0x10 [ 71.637915] ? _raw_spin_lock_irq+0x80/0xe0 [ 71.637915] ? _raw_spin_lock_irq+0x80/0xe0 [ 71.637915] ? __pfx__raw_spin_lock_irq+0x10/0x10 [ 71.637915] run_timer_softirq+0x141/0x240 [ 71.637915] ? __pfx_run_timer_softirq+0x10/0x10 [ 71.637915] ? __pfx___hrtimer_run_queues+0x10/0x10 [ 71.637915] ? kvm_clock_get_cycles+0x18/0x30 [ 71.637915] ? ktime_get+0x60/0x140 [ 71.637915] handle_softirqs+0x1b8/0x5c0 [ 71.637915] ? __pfx_handle_softirqs+0x10/0x10 [ 71.637915] irq_exit_rcu+0xaf/0xe0 [ 71.637915] sysvec_apic_timer_interrupt+0x6c/0x80 [ 71.637915] </IRQ> [ 71.637915] [ 71.637915] Allocated by task 39: [ 71.637915] kasan_save_stack+0x33/0x60 [ 71.637915] kasan_save_track+0x14/0x30 [ 71.637915] __kasan_kmalloc+0x8f/0xa0 [ 71.637915] __kmalloc_node_track_caller_noprof+0x195/0x420 [ 71.637915] devm_kmalloc+0x74/0x1e0 [ 71.637915] appletb_kbd_probe+0x37/0x3c0 [ 71.637915] hid_device_probe+0x2d1/0x680 [ 71.637915] really_probe+0x1c3/0x690 [ 71.637915] __driver_probe_device+0x247/0x300 [ 71.637915] driver_probe_device+0x49/0x210 [...] [ 71.637915] [ 71.637915] Freed by task 39: [ 71.637915] kasan_save_stack+0x33/0x60 [ 71.637915] kasan_save_track+0x14/0x30 [ 71.637915] kasan_save_free_info+0x3b/0x60 [ 71.637915] __kasan_slab_free+0x37/0x50 [ 71.637915] kfree+0xcf/0x360 [ 71.637915] devres_release_group+0x1f8/0x3c0 [ 71.637915] hid_device_probe+0x315/0x680 [ 71.637915] really_probe+0x1c3/0x690 [ 71.637915] __driver_probe_device+0x247/0x300 [ 71.637915] driver_probe_device+0x49/0x210 [...] The root cause of the issue is that the timer is not disarmed on failure paths leading to it remaining active and accessing freed memory. To fix this call timer_delete_sync() to deactivate the timer. Another small issue is that timer_delete_sync is called unconditionally in appletb_kbd_remove(), fix this by checking for a valid kbd->backlight_dev before calling timer_delete_sync. Fixes: 93a0fc4 ("HID: hid-appletb-kbd: add support for automatic brightness control while using the touchbar") Cc: [email protected] Signed-off-by: Qasim Ijaz <[email protected]> Reviewed-by: Aditya Garg <[email protected]> Signed-off-by: Jiri Kosina <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

Without the change `perf `hangs up on charaster devices. On my system it's enough to run system-wide sampler for a few seconds to get the hangup: $ perf record -a -g --call-graph=dwarf $ perf report # hung `strace` shows that hangup happens on reading on a character device `/dev/dri/renderD128` $ strace -y -f -p 2780484 strace: Process 2780484 attached pread64(101</dev/dri/renderD128>, strace: Process 2780484 detached It's call trace descends into `elfutils`: $ gdb -p 2780484 (gdb) bt #0 0x00007f5e508f04b7 in __libc_pread64 (fd=101, buf=0x7fff9df7edb0, count=0, offset=0) at ../sysdeps/unix/sysv/linux/pread64.c:25 gregkh#1 0x00007f5e52b79515 in read_file () from /<<NIX>>/elfutils-0.192/lib/libelf.so.1 gregkh#2 0x00007f5e52b25666 in libdw_open_elf () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 gregkh#3 0x00007f5e52b25907 in __libdw_open_file () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 gregkh#4 0x00007f5e52b120a9 in dwfl_report_elf@@ELFUTILS_0.156 () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 gregkh#5 0x000000000068bf20 in __report_module (al=al@entry=0x7fff9df80010, ip=ip@entry=139803237033216, ui=ui@entry=0x5369b5e0) at util/dso.h:537 gregkh#6 0x000000000068c3d1 in report_module (ip=139803237033216, ui=0x5369b5e0) at util/unwind-libdw.c:114 gregkh#7 frame_callback (state=0x535aef10, arg=0x5369b5e0) at util/unwind-libdw.c:242 gregkh#8 0x00007f5e52b261d3 in dwfl_thread_getframes () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 gregkh#9 0x00007f5e52b25bdb in get_one_thread_cb () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 gregkh#10 0x00007f5e52b25faa in dwfl_getthreads () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 gregkh#11 0x00007f5e52b26514 in dwfl_getthread_frames () from /<<NIX>>/elfutils-0.192/lib/libdw.so.1 gregkh#12 0x000000000068c6ce in unwind__get_entries (cb=cb@entry=0x5d4620 <unwind_entry>, arg=arg@entry=0x10cd5fa0, thread=thread@entry=0x1076a290, data=data@entry=0x7fff9df80540, max_stack=max_stack@entry=127, best_effort=best_effort@entry=false) at util/thread.h:152 gregkh#13 0x00000000005dae95 in thread__resolve_callchain_unwind (evsel=0x106006d0, thread=0x1076a290, cursor=0x10cd5fa0, sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2939 gregkh#14 thread__resolve_callchain_unwind (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, sample=0x7fff9df80540, max_stack=127, symbols=true) at util/machine.c:2920 gregkh#15 __thread__resolve_callchain (thread=0x1076a290, cursor=0x10cd5fa0, evsel=0x106006d0, evsel@entry=0x7fff9df80440, sample=0x7fff9df80540, parent=parent@entry=0x7fff9df804a0, root_al=root_al@entry=0x7fff9df80440, max_stack=127, symbols=true) at util/machine.c:2970 gregkh#16 0x00000000005d0cb2 in thread__resolve_callchain (thread=<optimized out>, cursor=<optimized out>, evsel=0x7fff9df80440, sample=<optimized out>, parent=0x7fff9df804a0, root_al=0x7fff9df80440, max_stack=127) at util/machine.h:198 gregkh#17 sample__resolve_callchain (sample=<optimized out>, cursor=<optimized out>, parent=parent@entry=0x7fff9df804a0, evsel=evsel@entry=0x106006d0, al=al@entry=0x7fff9df80440, max_stack=max_stack@entry=127) at util/callchain.c:1127 gregkh#18 0x0000000000617e08 in hist_entry_iter__add (iter=iter@entry=0x7fff9df80480, al=al@entry=0x7fff9df80440, max_stack_depth=127, arg=arg@entry=0x7fff9df81ae0) at util/hist.c:1255 gregkh#19 0x000000000045d2d0 in process_sample_event (tool=0x7fff9df81ae0, event=<optimized out>, sample=0x7fff9df80540, evsel=0x106006d0, machine=<optimized out>) at builtin-report.c:334 gregkh#20 0x00000000005e3bb1 in perf_session__deliver_event (session=0x105ff2c0, event=0x7f5c7d735ca0, tool=0x7fff9df81ae0, file_offset=2914716832, file_path=0x105ffbf0 "perf.data") at util/session.c:1367 gregkh#21 0x00000000005e8d93 in do_flush (oe=0x105ffa50, show_progress=false) at util/ordered-events.c:245 gregkh#22 __ordered_events__flush (oe=0x105ffa50, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:324 #23 0x00000000005e1f64 in perf_session__process_user_event (session=0x105ff2c0, event=0x7f5c7d752b18, file_offset=2914835224, file_path=0x105ffbf0 "perf.data") at util/session.c:1419 #24 0x00000000005e47c7 in reader__read_event (rd=rd@entry=0x7fff9df81260, session=session@entry=0x105ff2c0, --Type <RET> for more, q to quit, c to continue without paging-- quit prog=prog@entry=0x7fff9df81220) at util/session.c:2132 #25 0x00000000005e4b37 in reader__process_events (rd=0x7fff9df81260, session=0x105ff2c0, prog=0x7fff9df81220) at util/session.c:2181 #26 __perf_session__process_events (session=0x105ff2c0) at util/session.c:2226 #27 perf_session__process_events (session=session@entry=0x105ff2c0) at util/session.c:2390 #28 0x0000000000460add in __cmd_report (rep=0x7fff9df81ae0) at builtin-report.c:1076 #29 cmd_report (argc=<optimized out>, argv=<optimized out>) at builtin-report.c:1827 #30 0x00000000004c5a40 in run_builtin (p=p@entry=0xd8f7f8 <commands+312>, argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:351 #31 0x00000000004c5d63 in handle_internal_command (argc=argc@entry=1, argv=argv@entry=0x7fff9df844b0) at perf.c:404 #32 0x0000000000442de3 in run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:448 #33 main (argc=<optimized out>, argv=0x7fff9df844b0) at perf.c:556 The hangup happens because nothing in` perf` or `elfutils` checks if a mapped file is easily readable. The change conservatively skips all non-regular files. Signed-off-by: Sergei Trofimovich <[email protected]> Acked-by: Namhyung Kim <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>

Symbolize stack traces by creating a live machine. Add this functionality to dump_stack and switch dump_stack users to use it. Switch TUI to use it. Add stack traces to the child test function which can be useful to diagnose blocked code. Example output: ``` $ perf test -vv PERF_RECORD_ ... 7: PERF_RECORD_* events & perf_sample fields: 7: PERF_RECORD_* events & perf_sample fields : Running (1 active) ^C Signal (2) while running tests. Terminating tests with the same signal Internal test harness failure. Completing any started tests: : 7: PERF_RECORD_* events & perf_sample fields: ---- unexpected signal (2) ---- #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0 gregkh#1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 gregkh#2 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64 gregkh#3 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72 gregkh#4 0x7fc12fef1393 in __nanosleep nanosleep.c:26 gregkh#5 0x7fc12ff02d68 in __sleep sleep.c:55 gregkh#6 0x55788c63196b in test__PERF_RECORD perf-record.c:0 gregkh#7 0x55788c620fb0 in run_test_child builtin-test.c:0 gregkh#8 0x55788c5bd18d in start_command run-command.c:127 gregkh#9 0x55788c621ef3 in __cmd_test builtin-test.c:0 gregkh#10 0x55788c6225bf in cmd_test ??:0 gregkh#11 0x55788c5afbd0 in run_builtin perf.c:0 gregkh#12 0x55788c5afeeb in handle_internal_command perf.c:0 gregkh#13 0x55788c52b383 in main ??:0 gregkh#14 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74 gregkh#15 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 gregkh#16 0x55788c52b9d1 in _start ??:0 ---- unexpected signal (2) ---- #0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0 gregkh#1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 gregkh#2 0x7fc12fea3a14 in pthread_sigmask@GLIBC_2.2.5 pthread_sigmask.c:45 gregkh#3 0x7fc12fe49fd9 in __GI___sigprocmask sigprocmask.c:26 gregkh#4 0x7fc12ff2601b in __longjmp_chk longjmp.c:36 gregkh#5 0x55788c6210c0 in print_test_result.isra.0 builtin-test.c:0 gregkh#6 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0 gregkh#7 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64 gregkh#8 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72 gregkh#9 0x7fc12fef1393 in __nanosleep nanosleep.c:26 gregkh#10 0x7fc12ff02d68 in __sleep sleep.c:55 gregkh#11 0x55788c63196b in test__PERF_RECORD perf-record.c:0 gregkh#12 0x55788c620fb0 in run_test_child builtin-test.c:0 gregkh#13 0x55788c5bd18d in start_command run-command.c:127 gregkh#14 0x55788c621ef3 in __cmd_test builtin-test.c:0 gregkh#15 0x55788c6225bf in cmd_test ??:0 gregkh#16 0x55788c5afbd0 in run_builtin perf.c:0 gregkh#17 0x55788c5afeeb in handle_internal_command perf.c:0 gregkh#18 0x55788c52b383 in main ??:0 gregkh#19 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74 gregkh#20 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 gregkh#21 0x55788c52b9d1 in _start ??:0 7: PERF_RECORD_* events & perf_sample fields : Skip (permissions) ``` Signed-off-by: Ian Rogers <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>

Calling perf top with branch filters enabled on Intel CPU's with branch counters logging (A.K.A LBR event logging [1]) support results in a segfault. $ perf top -e '{cpu_core/cpu-cycles/,cpu_core/event=0xc6,umask=0x3,frontend=0x11,name=frontend_retired_dsb_miss/}' -j any,counter ... Thread 27 "perf" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fffafff76c0 (LWP 949003)] perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653 653 *width = env->cpu_pmu_caps ? env->br_cntr_width : (gdb) bt #0 perf_env__find_br_cntr_info (env=0xf66dc0 <perf_env>, nr=0x0, width=0x7fffafff62c0) at util/env.c:653 gregkh#1 0x00000000005b1599 in symbol__account_br_cntr (branch=0x7fffcc3db580, evsel=0xfea2d0, offset=12, br_cntr=8) at util/annotate.c:345 gregkh#2 0x00000000005b17fb in symbol__account_cycles (addr=5658172, start=5658160, sym=0x7fffcc0ee420, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:389 gregkh#3 0x00000000005b1976 in addr_map_symbol__account_cycles (ams=0x7fffcd7b01d0, start=0x7fffcd7b02b0, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:422 gregkh#4 0x000000000068d57f in hist__account_cycles (bs=0x110d288, al=0x7fffafff6540, sample=0x7fffafff6760, nonany_branch_mode=false, total_cycles=0x0, evsel=0xfea2d0) at util/hist.c:2850 gregkh#5 0x0000000000446216 in hist_iter__top_callback (iter=0x7fffafff6590, al=0x7fffafff6540, single=true, arg=0x7fffffff9e00) at builtin-top.c:737 gregkh#6 0x0000000000689787 in hist_entry_iter__add (iter=0x7fffafff6590, al=0x7fffafff6540, max_stack_depth=127, arg=0x7fffffff9e00) at util/hist.c:1359 gregkh#7 0x0000000000446710 in perf_event__process_sample (tool=0x7fffffff9e00, event=0x110d250, evsel=0xfea2d0, sample=0x7fffafff6760, machine=0x108c968) at builtin-top.c:845 gregkh#8 0x0000000000447735 in deliver_event (qe=0x7fffffffa120, qevent=0x10fc200) at builtin-top.c:1211 gregkh#9 0x000000000064ccae in do_flush (oe=0x7fffffffa120, show_progress=false) at util/ordered-events.c:245 gregkh#10 0x000000000064d005 in __ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP, timestamp=0) at util/ordered-events.c:324 gregkh#11 0x000000000064d0ef in ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP) at util/ordered-events.c:342 gregkh#12 0x00000000004472a9 in process_thread (arg=0x7fffffff9e00) at builtin-top.c:1120 gregkh#13 0x00007ffff6e7dba8 in start_thread (arg=<optimized out>) at pthread_create.c:448 gregkh#14 0x00007ffff6f01b8c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78 The cause is that perf_env__find_br_cntr_info tries to access a null pointer pmu_caps in the perf_env struct. A similar issue exists for homogeneous core systems which use the cpu_pmu_caps structure. Fix this by populating cpu_pmu_caps and pmu_caps structures with values from sysfs when calling perf top with branch stack sampling enabled. [1], LBR event logging introduced here: https://lore.kernel.org/all/[email protected]/ Reviewed-by: Ian Rogers <[email protected]> Signed-off-by: Thomas Falcon <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>

Receiving HSR frame with insufficient space to hold HSR tag in the skb can result in a crash (kernel BUG): [ 45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1 [ 45.392559] ------------[ cut here ]------------ [ 45.392912] kernel BUG at net/core/skbuff.c:211! [ 45.393276] Oops: invalid opcode: 0000 [gregkh#1] SMP DEBUG_PAGEALLOC KASAN NOPTI [ 45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 gregkh#12 PREEMPT(undef) [ 45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 45.395273] RIP: 0010:skb_panic+0x15b/0x1d0 <snip registers, remove unreliable trace> [ 45.402911] Call Trace: [ 45.403105] <IRQ> [ 45.404470] skb_push+0xcd/0xf0 [ 45.404726] br_dev_queue_push_xmit+0x7c/0x6c0 [ 45.406513] br_forward_finish+0x128/0x260 [ 45.408483] __br_forward+0x42d/0x590 [ 45.409464] maybe_deliver+0x2eb/0x420 [ 45.409763] br_flood+0x174/0x4a0 [ 45.410030] br_handle_frame_finish+0xc7c/0x1bc0 [ 45.411618] br_handle_frame+0xac3/0x1230 [ 45.413674] __netif_receive_skb_core.constprop.0+0x808/0x3df0 [ 45.422966] __netif_receive_skb_one_core+0xb4/0x1f0 [ 45.424478] __netif_receive_skb+0x22/0x170 [ 45.424806] process_backlog+0x242/0x6d0 [ 45.425116] __napi_poll+0xbb/0x630 [ 45.425394] net_rx_action+0x4d1/0xcc0 [ 45.427613] handle_softirqs+0x1a4/0x580 [ 45.427926] do_softirq+0x74/0x90 [ 45.428196] </IRQ> This issue was found by syzkaller. The panic happens in br_dev_queue_push_xmit() once it receives a corrupted skb with ETH header already pushed in linear data. When it attempts the skb_push() call, there's not enough headroom and skb_push() panics. The corrupted skb is put on the queue by HSR layer, which makes a sequence of unintended transformations when it receives a specific corrupted HSR frame (with incomplete TAG). Fix it by dropping and consuming frames that are not long enough to contain both ethernet and hsr headers. Alternative fix would be to check for enough headroom before skb_push() in br_dev_queue_push_xmit(). In the reproducer, this is injected via AF_PACKET, but I don't easily see why it couldn't be sent over the wire from adjacent network. Further Details: In the reproducer, the following network interface chain is set up: ┌────────────────┐ ┌────────────────┐ │ veth0_to_hsr ├───┤ hsr_slave0 ┼───┐ └────────────────┘ └────────────────┘ │ │ ┌──────┐ ├─┤ hsr0 ├───┐ │ └──────┘ │ ┌────────────────┐ ┌────────────────┐ │ │┌────────┐ │ veth1_to_hsr ┼───┤ hsr_slave1 ├───┘ └┤ │ └────────────────┘ └────────────────┘ ┌┼ bridge │ ││ │ │└────────┘ │ ┌───────┐ │ │ ... ├──────┘ └───────┘ To trigger the events leading up to crash, reproducer sends a corrupted HSR frame with incomplete TAG, via AF_PACKET socket on 'veth0_to_hsr'. The first HSR-layer function to process this frame is hsr_handle_frame(). It and then checks if the protocol is ETH_P_PRP or ETH_P_HSR. If it is, it calls skb_set_network_header(skb, ETH_HLEN + HSR_HLEN), without checking that the skb is long enough. For the crashing frame it is not, and hence the skb->network_header and skb->mac_len fields are set incorrectly, pointing after the end of the linear buffer. I will call this a BUG#1 and it is what is addressed by this patch. In the crashing scenario before the fix, the skb continues to go down the hsr path as follows. hsr_handle_frame() then calls this sequence hsr_forward_skb() fill_frame_info() hsr->proto_ops->fill_frame_info() hsr_fill_frame_info() hsr_fill_frame_info() contains a check that intends to check whether the skb actually contains the HSR header. But the check relies on the skb->mac_len field which was erroneously setup due to BUG#1, so the check passes and the execution continues back in the hsr_forward_skb(): hsr_forward_skb() hsr_forward_do() hsr->proto_ops->get_untagged_frame() hsr_get_untagged_frame() create_stripped_skb_hsr() In create_stripped_skb_hsr(), a copy of the skb is created and is further corrupted by operation that attempts to strip the HSR tag in a call to __pskb_copy(). The skb enters create_stripped_skb_hsr() with ethernet header pushed in linear buffer. The skb_pull(skb_in, HSR_HLEN) thus pulls 6 bytes of ethernet header into the headroom, creating skb_in with a headroom of size 8. The subsequent __pskb_copy() then creates an skb with headroom of just 2 and skb->len of just 12, this is how it looks after the copy: gdb) p skb->len $10 = 12 (gdb) p skb->data $11 = (unsigned char *) 0xffff888041e45382 "\252\252\252\252\252!\210\373", (gdb) p skb->head $12 = (unsigned char *) 0xffff888041e45380 "" It seems create_stripped_skb_hsr() assumes that ETH header is pulled in the headroom when it's entered, because it just pulls HSR header on top. But that is not the case in our code-path and we end up with the corrupted skb instead. I will call this BUG#2 *I got confused here because it seems that under no conditions can create_stripped_skb_hsr() work well, the assumption it makes is not true during the processing of hsr frames - since the skb_push() in hsr_handle_frame to skb_pull in hsr_deliver_master(). I wonder whether I missed something here.* Next, the execution arrives in hsr_deliver_master(). It calls skb_pull(ETH_HLEN), which just returns NULL - the SKB does not have enough space for the pull (as it only has 12 bytes in total at this point). *The skb_pull() here further suggests that ethernet header is meant to be pushed through the whole hsr processing and create_stripped_skb_hsr() should pull it before doing the HSR header pull.* hsr_deliver_master() then puts the corrupted skb on the queue, it is then picked up from there by bridge frame handling layer and finally lands in br_dev_queue_push_xmit where it panics. Cc: [email protected] Fixes: 48b491a ("net: hsr: fix mac_len checks") Reported-by: [email protected] Signed-off-by: Jakub Acs <[email protected]> Reviewed-by: Eric Dumazet <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

commit 7af76e9 upstream. Receiving HSR frame with insufficient space to hold HSR tag in the skb can result in a crash (kernel BUG): [ 45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1 [ 45.392559] ------------[ cut here ]------------ [ 45.392912] kernel BUG at net/core/skbuff.c:211! [ 45.393276] Oops: invalid opcode: 0000 [gregkh#1] SMP DEBUG_PAGEALLOC KASAN NOPTI [ 45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 gregkh#12 PREEMPT(undef) [ 45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 45.395273] RIP: 0010:skb_panic+0x15b/0x1d0 <snip registers, remove unreliable trace> [ 45.402911] Call Trace: [ 45.403105] <IRQ> [ 45.404470] skb_push+0xcd/0xf0 [ 45.404726] br_dev_queue_push_xmit+0x7c/0x6c0 [ 45.406513] br_forward_finish+0x128/0x260 [ 45.408483] __br_forward+0x42d/0x590 [ 45.409464] maybe_deliver+0x2eb/0x420 [ 45.409763] br_flood+0x174/0x4a0 [ 45.410030] br_handle_frame_finish+0xc7c/0x1bc0 [ 45.411618] br_handle_frame+0xac3/0x1230 [ 45.413674] __netif_receive_skb_core.constprop.0+0x808/0x3df0 [ 45.422966] __netif_receive_skb_one_core+0xb4/0x1f0 [ 45.424478] __netif_receive_skb+0x22/0x170 [ 45.424806] process_backlog+0x242/0x6d0 [ 45.425116] __napi_poll+0xbb/0x630 [ 45.425394] net_rx_action+0x4d1/0xcc0 [ 45.427613] handle_softirqs+0x1a4/0x580 [ 45.427926] do_softirq+0x74/0x90 [ 45.428196] </IRQ> This issue was found by syzkaller. The panic happens in br_dev_queue_push_xmit() once it receives a corrupted skb with ETH header already pushed in linear data. When it attempts the skb_push() call, there's not enough headroom and skb_push() panics. The corrupted skb is put on the queue by HSR layer, which makes a sequence of unintended transformations when it receives a specific corrupted HSR frame (with incomplete TAG). Fix it by dropping and consuming frames that are not long enough to contain both ethernet and hsr headers. Alternative fix would be to check for enough headroom before skb_push() in br_dev_queue_push_xmit(). In the reproducer, this is injected via AF_PACKET, but I don't easily see why it couldn't be sent over the wire from adjacent network. Further Details: In the reproducer, the following network interface chain is set up: ┌────────────────┐ ┌────────────────┐ │ veth0_to_hsr ├───┤ hsr_slave0 ┼───┐ └────────────────┘ └────────────────┘ │ │ ┌──────┐ ├─┤ hsr0 ├───┐ │ └──────┘ │ ┌────────────────┐ ┌────────────────┐ │ │┌────────┐ │ veth1_to_hsr ┼───┤ hsr_slave1 ├───┘ └┤ │ └────────────────┘ └────────────────┘ ┌┼ bridge │ ││ │ │└────────┘ │ ┌───────┐ │ │ ... ├──────┘ └───────┘ To trigger the events leading up to crash, reproducer sends a corrupted HSR frame with incomplete TAG, via AF_PACKET socket on 'veth0_to_hsr'. The first HSR-layer function to process this frame is hsr_handle_frame(). It and then checks if the protocol is ETH_P_PRP or ETH_P_HSR. If it is, it calls skb_set_network_header(skb, ETH_HLEN + HSR_HLEN), without checking that the skb is long enough. For the crashing frame it is not, and hence the skb->network_header and skb->mac_len fields are set incorrectly, pointing after the end of the linear buffer. I will call this a BUG#1 and it is what is addressed by this patch. In the crashing scenario before the fix, the skb continues to go down the hsr path as follows. hsr_handle_frame() then calls this sequence hsr_forward_skb() fill_frame_info() hsr->proto_ops->fill_frame_info() hsr_fill_frame_info() hsr_fill_frame_info() contains a check that intends to check whether the skb actually contains the HSR header. But the check relies on the skb->mac_len field which was erroneously setup due to BUG#1, so the check passes and the execution continues back in the hsr_forward_skb(): hsr_forward_skb() hsr_forward_do() hsr->proto_ops->get_untagged_frame() hsr_get_untagged_frame() create_stripped_skb_hsr() In create_stripped_skb_hsr(), a copy of the skb is created and is further corrupted by operation that attempts to strip the HSR tag in a call to __pskb_copy(). The skb enters create_stripped_skb_hsr() with ethernet header pushed in linear buffer. The skb_pull(skb_in, HSR_HLEN) thus pulls 6 bytes of ethernet header into the headroom, creating skb_in with a headroom of size 8. The subsequent __pskb_copy() then creates an skb with headroom of just 2 and skb->len of just 12, this is how it looks after the copy: gdb) p skb->len $10 = 12 (gdb) p skb->data $11 = (unsigned char *) 0xffff888041e45382 "\252\252\252\252\252!\210\373", (gdb) p skb->head $12 = (unsigned char *) 0xffff888041e45380 "" It seems create_stripped_skb_hsr() assumes that ETH header is pulled in the headroom when it's entered, because it just pulls HSR header on top. But that is not the case in our code-path and we end up with the corrupted skb instead. I will call this BUG#2 *I got confused here because it seems that under no conditions can create_stripped_skb_hsr() work well, the assumption it makes is not true during the processing of hsr frames - since the skb_push() in hsr_handle_frame to skb_pull in hsr_deliver_master(). I wonder whether I missed something here.* Next, the execution arrives in hsr_deliver_master(). It calls skb_pull(ETH_HLEN), which just returns NULL - the SKB does not have enough space for the pull (as it only has 12 bytes in total at this point). *The skb_pull() here further suggests that ethernet header is meant to be pushed through the whole hsr processing and create_stripped_skb_hsr() should pull it before doing the HSR header pull.* hsr_deliver_master() then puts the corrupted skb on the queue, it is then picked up from there by bridge frame handling layer and finally lands in br_dev_queue_push_xmit where it panics. Cc: [email protected] Fixes: 48b491a ("net: hsr: fix mac_len checks") Reported-by: [email protected] Signed-off-by: Jakub Acs <[email protected]> Reviewed-by: Eric Dumazet <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

…CAN XL step 3/3" Vincent Mailhol <[email protected]> says: In November last year, I sent an RFC to introduce CAN XL [1]. That RFC, despite positive feedback, was put on hold due to some unanswered question concerning the PWM encoding [2]. While stuck, some small preparation work was done in parallel in [3] by refactoring the struct can_priv and doing some trivial clean-up and renaming. Initially, [3] received zero feedback but was eventually merged after splitting it in smaller parts and resending it. Finally, in July this year, we clarified the remaining mysteries about PWM calculation, thus unlocking the series. Summer being a bit busy because of some personal matters brings us to now. After doing all the refactoring and adding all the CAN XL features, the final result is more than 30 patches, definitively too much for a single series. So I am splitting the remaining changes three: - can: rework the CAN MTU logic [4] - can: netlink: preparation before introduction of CAN XL (this series) - CAN XL (will come right after the two preparation series get merged) And thus, this series continues and finishes the preparation work done in [3] and [4]. It contains all the refactoring needed to smoothly introduce CAN XL. The goal is to: - split the functions in smaller pieces: CAN XL will introduce a fair amount of code. And some functions which are already fairly long (86 lines for can_validate(), 215 lines for can_changelink()) would grow to disproportionate sizes if the CAN XL logic were to be inlined in those functions. - repurpose the existing code to handle both CAN FD and CAN XL: a huge part of CAN XL simply reuses the CAN FD logic. All the existing CAN FD logic is made more generic to handle both CAN FD and XL. In more details: - Patch gregkh#1 moves struct data_bittiming_params from dev.h to bittiming.h and patch gregkh#2 makes can_get_relative_tdco() FD agnostic before also moving it to bittiming.h. - Patch gregkh#3 adds some comments to netlink.h tagging which IFLA symbols are FD specific. - Patches gregkh#4 to gregkh#6 are refactoring can_validate() and can_validate_bittiming(). - Patches gregkh#7 to gregkh#11 are refactoring can_changelink() and can_tdc_changelink(). - Patches gregkh#12 and gregkh#13 are refactoring can_get_size() and can_tdc_get_size(). - Patches gregkh#14 to gregkh#17 are refactoring can_fill_info() and can_tdc_fill_info(). - Patch gregkh#18 makes can_calc_tdco() FD agnostic. - Patch gregkh#19 adds can_get_ctrlmode_str() which converts control mode flags into strings. This is done in preparation of patch gregkh#20. - Patch gregkh#20 is the final patch and improves the user experience by providing detailed error messages whenever invalid parameters are provided. All those error messages came into handy when debugging the upcoming CAN XL patches. Aside from the last patch, the other changes do not impact any of the existing functionalities. The follow up series which introduces CAN XL is nearly completed but will be sent only once this one is approved: one thing at a time, I do not want to overwhelm people (including myself). [1] https://lore.kernel.org/linux-can/[email protected]/ [2] https://lore.kernel.org/linux-can/[email protected]/ [3] https://lore.kernel.org/linux-can/[email protected]/ [4] https://lore.kernel.org/linux-can/[email protected]/ Link: https://patch.msgid.link/[email protected] Signed-off-by: Marc Kleine-Budde <[email protected]>

Petr Machata says: ==================== selftests: Mark auto-deferring functions clearly selftests/net/lib.sh contains a suite of iproute2 wrappers that automatically schedule the corresponding cleanup through defer. The fact they do so is however not immediately obvious, one needs to know which functions are handling the deferral behind the scenes, and which expect the caller to handle cleanups themselves. A convention for these auto-deferring functions would help both writing and patch review. This patchset does so by marking these functions with an adf_ prefix. We already have a few such functions: forwarding/lib.sh has adf_mcd_start() and a few selftests add private helpers that conform to this convention. Patches gregkh#1 to gregkh#8 gradually convert individual functions, one per patch. Patch gregkh#9 renames an auto-deferring private helpers named dfr_* to adf_*. The plan is not to retro-rename all private helpers, but I happened to know about this one. Patches gregkh#10 to gregkh#12 introduce several autodefer helpers for commonly used forwarding/lib.sh functions, and opportunistically convert straightforward instances of 'action; defer counteraction' to the new helpers. Patch gregkh#13 adds some README verbiage to pitch defer and the adf_* convention. ==================== Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

The test starts a workload and then opens events. If the events fail to open, for example because of perf_event_paranoid, the gopipe of the workload is leaked and the file descriptor leak check fails when the test exits. To avoid this cancel the workload when opening the events fails. Before: ``` $ perf test -vv 7 7: PERF_RECORD_* events & perf_sample fields: --- start --- test child forked, pid 1189568 Using CPUID GenuineIntel-6-B7-1 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 exclude_kernel 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 exclude_kernel 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3 Attempt to add: software/cpu-clock/ ..after resolving event: software/config=0/ cpu-clock -> software/cpu-clock/ ------------------------------------------------------------ perf_event_attr: type 1 (PERF_TYPE_SOFTWARE) size 136 config 0x9 (PERF_COUNT_SW_DUMMY) sample_type IP|TID|TIME|CPU read_format ID|LOST disabled 1 inherit 1 mmap 1 comm 1 enable_on_exec 1 task 1 sample_id_all 1 mmap2 1 comm_exec 1 ksymbol 1 bpf_event 1 { wakeup_events, wakeup_watermark } 1 ------------------------------------------------------------ sys_perf_event_open: pid 1189569 cpu 0 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 perf_evlist__open: Permission denied ---- end(-2) ---- Leak of file descriptor 6 that opened: 'pipe:[14200347]' ---- unexpected signal (6) ---- iFailed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon #0 0x565358f6666e in child_test_sig_handler builtin-test.c:311 gregkh#1 0x7f29ce849df0 in __restore_rt libc_sigaction.c:0 gregkh#2 0x7f29ce89e95c in __pthread_kill_implementation pthread_kill.c:44 gregkh#3 0x7f29ce849cc2 in raise raise.c:27 gregkh#4 0x7f29ce8324ac in abort abort.c:81 gregkh#5 0x565358f662d4 in check_leaks builtin-test.c:226 gregkh#6 0x565358f6682e in run_test_child builtin-test.c:344 gregkh#7 0x565358ef7121 in start_command run-command.c:128 gregkh#8 0x565358f67273 in start_test builtin-test.c:545 gregkh#9 0x565358f6771d in __cmd_test builtin-test.c:647 gregkh#10 0x565358f682bd in cmd_test builtin-test.c:849 gregkh#11 0x565358ee5ded in run_builtin perf.c:349 gregkh#12 0x565358ee6085 in handle_internal_command perf.c:401 gregkh#13 0x565358ee61de in run_argv perf.c:448 gregkh#14 0x565358ee6527 in main perf.c:555 gregkh#15 0x7f29ce833ca8 in __libc_start_call_main libc_start_call_main.h:74 gregkh#16 0x7f29ce833d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 gregkh#17 0x565358e391c1 in _start perf[851c1] 7: PERF_RECORD_* events & perf_sample fields : FAILED! ``` After: ``` $ perf test 7 7: PERF_RECORD_* events & perf_sample fields : Skip (permissions) ``` Fixes: 16d00fe ("perf tests: Move test__PERF_RECORD into separate object") Signed-off-by: Ian Rogers <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Athira Rajeev <[email protected]> Cc: Chun-Tse Shao <[email protected]> Cc: Howard Chu <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

[ Upstream commit 48918ca ] The test starts a workload and then opens events. If the events fail to open, for example because of perf_event_paranoid, the gopipe of the workload is leaked and the file descriptor leak check fails when the test exits. To avoid this cancel the workload when opening the events fails. Before: ``` $ perf test -vv 7 7: PERF_RECORD_* events & perf_sample fields: --- start --- test child forked, pid 1189568 Using CPUID GenuineIntel-6-B7-1 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0xa00000000 (cpu_atom/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 exclude_kernel 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) config 0x400000000 (cpu_core/PERF_COUNT_HW_CPU_CYCLES/) disabled 1 exclude_kernel 1 ------------------------------------------------------------ sys_perf_event_open: pid 0 cpu -1 group_fd -1 flags 0x8 = 3 Attempt to add: software/cpu-clock/ ..after resolving event: software/config=0/ cpu-clock -> software/cpu-clock/ ------------------------------------------------------------ perf_event_attr: type 1 (PERF_TYPE_SOFTWARE) size 136 config 0x9 (PERF_COUNT_SW_DUMMY) sample_type IP|TID|TIME|CPU read_format ID|LOST disabled 1 inherit 1 mmap 1 comm 1 enable_on_exec 1 task 1 sample_id_all 1 mmap2 1 comm_exec 1 ksymbol 1 bpf_event 1 { wakeup_events, wakeup_watermark } 1 ------------------------------------------------------------ sys_perf_event_open: pid 1189569 cpu 0 group_fd -1 flags 0x8 sys_perf_event_open failed, error -13 perf_evlist__open: Permission denied ---- end(-2) ---- Leak of file descriptor 6 that opened: 'pipe:[14200347]' ---- unexpected signal (6) ---- iFailed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon Failed to read build ID for //anon #0 0x565358f6666e in child_test_sig_handler builtin-test.c:311 #1 0x7f29ce849df0 in __restore_rt libc_sigaction.c:0 #2 0x7f29ce89e95c in __pthread_kill_implementation pthread_kill.c:44 #3 0x7f29ce849cc2 in raise raise.c:27 #4 0x7f29ce8324ac in abort abort.c:81 #5 0x565358f662d4 in check_leaks builtin-test.c:226 #6 0x565358f6682e in run_test_child builtin-test.c:344 #7 0x565358ef7121 in start_command run-command.c:128 #8 0x565358f67273 in start_test builtin-test.c:545 #9 0x565358f6771d in __cmd_test builtin-test.c:647 #10 0x565358f682bd in cmd_test builtin-test.c:849 #11 0x565358ee5ded in run_builtin perf.c:349 #12 0x565358ee6085 in handle_internal_command perf.c:401 #13 0x565358ee61de in run_argv perf.c:448 #14 0x565358ee6527 in main perf.c:555 #15 0x7f29ce833ca8 in __libc_start_call_main libc_start_call_main.h:74 #16 0x7f29ce833d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128 #17 0x565358e391c1 in _start perf[851c1] 7: PERF_RECORD_* events & perf_sample fields : FAILED! ``` After: ``` $ perf test 7 7: PERF_RECORD_* events & perf_sample fields : Skip (permissions) ``` Fixes: 16d00fe ("perf tests: Move test__PERF_RECORD into separate object") Signed-off-by: Ian Rogers <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Athira Rajeev <[email protected]> Cc: Chun-Tse Shao <[email protected]> Cc: Howard Chu <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

Marc Kleine-Budde <[email protected]> says: Similarly to how CAN FD reuses the bittiming logic of Classical CAN, CAN XL also reuses the entirety of CAN FD features, and, on top of that, adds new features which are specific to CAN XL. A so-called 'mixed-mode' is intended to have (XL-tolerant) CAN FD nodes and CAN XL nodes on one CAN segment, where the FD-controllers can talk CC/FD and the XL-controllers can talk CC/FD/XL. This mixed-mode utilizes the known error-signalling (ES) for sending CC/FD/XL frames. For CAN FD and CAN XL the tranceiver delay compensation (TDC) is supported to use common CAN and CAN-SIG transceivers. The CANXL-only mode disables the error-signalling in the CAN XL controller. This mode does not allow CC/FD frames to be sent but additionally offers a CAN XL transceiver mode switching (TMS) to send CAN XL frames with up to 20Mbit/s data rate. The TMS utilizes a PWM configuration which is added to the netlink interface. Configured with CAN_CTRLMODE_FD and CAN_CTRLMODE_XL this leads to: FD=0 XL=0 CC-only mode (ES=1) FD=1 XL=0 FD/CC mixed-mode (ES=1) FD=1 XL=1 XL/FD/CC mixed-mode (ES=1) FD=0 XL=1 XL-only mode (ES=0, TMS optional) Patch gregkh#1 print defined ctrlmode strings capitalized to increase the readability and to be in line with the 'ip' tool (iproute2). Patch gregkh#2 is a small clean-up which makes can_calc_bittiming() use NL_SET_ERR_MSG() instead of netdev_err(). Patch gregkh#3 adds a check in can_dev_dropped_skb() to drop CAN FD frames when CAN FD is turned off. Patch gregkh#4 adds CAN_CTRLMODE_RESTRICTED. Note that contrary to the other CAN_CTRL_MODE_XL_* that are introduced in the later patches, this control mode is not specific to CAN XL. The nuance is that because this restricted mode was only added in ISO 11898-1:2024, it is made mandatory for CAN XL devices but optional for other protocols. This is why this patch is added as a preparation before introducing the core CAN XL logic. Patch gregkh#5 adds all the CAN XL features which are inherited from CAN FD: the nominal bittiming, the data bittiming and the TDC. Patch gregkh#6 add a new CAN_CTRLMODE_XL_TMS control mode which is specific to CAN XL to enable the transceiver mode switching (TMS) in XL-only mode. Patch gregkh#7 adds a check in can_dev_dropped_skb() to drop CAN CC/FD frames when the CAN XL controller is in CAN XL-only mode. The introduced can_dev_in_xl_only_mode() function also determines the error-signalling configuration for the CAN XL controllers. Patch gregkh#8 to gregkh#11 add the PWM logic for the CAN XL TMS mode. Patch gregkh#12 to gregkh#14 add different default sample-points for standard CAN and CAN SIG transceivers (with TDC) and CAN XL transceivers using PWM in the CAN XL TMS mode. Patch gregkh#15 add a dummy_can driver for netlink testing and debugging. Patch gregkh#16 check CAN frame type (CC/FD/XL) when writing those frames to the CAN_RAW socket and reject them if it's not supported by the CAN interface. Patch gregkh#17 increase the resolution when printing the bitrate error and round-up the value to 0.01% in the case the resolution would still provide values which would lead to 0.00%. Link: https://patch.msgid.link/[email protected] Signed-off-by: Marc Kleine-Budde <[email protected]>

On systems using the hash MMU, there is a software SLB preload cache that mirrors the entries loaded into the hardware SLB buffer. This preload cache is subject to periodic eviction — typically after every 256 context switches — to remove old entry. To optimize performance, the kernel skips switch_mmu_context() in switch_mm_irqs_off() when the prev and next mm_struct are the same. However, on hash MMU systems, this can lead to inconsistencies between the hardware SLB and the software preload cache. If an SLB entry for a process is evicted from the software cache on one CPU, and the same process later runs on another CPU without executing switch_mmu_context(), the hardware SLB may retain stale entries. If the kernel then attempts to reload that entry, it can trigger an SLB multi-hit error. The following timeline shows how stale SLB entries are created and can cause a multi-hit error when a process moves between CPUs without a MMU context switch. CPU 0 CPU 1 ----- ----- Process P exec swapper/1 load_elf_binary begin_new_exc activate_mm switch_mm_irqs_off switch_mmu_context switch_slb /* * This invalidates all * the entries in the HW * and setup the new HW * SLB entries as per the * preload cache. */ context_switch sched_migrate_task migrates process P to cpu-1 Process swapper/0 context switch (to process P) (uses mm_struct of Process P) switch_mm_irqs_off() switch_slb load_slb++ /* * load_slb becomes 0 here * and we evict an entry from * the preload cache with * preload_age(). We still * keep HW SLB and preload * cache in sync, that is * because all HW SLB entries * anyways gets evicted in * switch_slb during SLBIA. * We then only add those * entries back in HW SLB, * which are currently * present in preload_cache * (after eviction). */ load_elf_binary continues... setup_new_exec() slb_setup_new_exec() sched_switch event sched_migrate_task migrates process P to cpu-0 context_switch from swapper/0 to Process P switch_mm_irqs_off() /* * Since both prev and next mm struct are same we don't call * switch_mmu_context(). This will cause the HW SLB and SW preload * cache to go out of sync in preload_new_slb_context. Because there * was an SLB entry which was evicted from both HW and preload cache * on cpu-1. Now later in preload_new_slb_context(), when we will try * to add the same preload entry again, we will add this to the SW * preload cache and then will add it to the HW SLB. Since on cpu-0 * this entry was never invalidated, hence adding this entry to the HW * SLB will cause a SLB multi-hit error. */ load_elf_binary continues... START_THREAD start_thread preload_new_slb_context /* * This tries to add a new EA to preload cache which was earlier * evicted from both cpu-1 HW SLB and preload cache. This caused the * HW SLB of cpu-0 to go out of sync with the SW preload cache. The * reason for this was, that when we context switched back on CPU-0, * we should have ideally called switch_mmu_context() which will * bring the HW SLB entries on CPU-0 in sync with SW preload cache * entries by setting up the mmu context properly. But we didn't do * that since the prev mm_struct running on cpu-0 was same as the * next mm_struct (which is true for swapper / kernel threads). So * now when we try to add this new entry into the HW SLB of cpu-0, * we hit a SLB multi-hit error. */ WARNING: CPU: 0 PID: 1810970 at arch/powerpc/mm/book3s64/slb.c:62 assert_slb_presence+0x2c/0x50(48 results) 02:47:29 [20157/42149] Modules linked in: CPU: 0 UID: 0 PID: 1810970 Comm: dd Not tainted 6.16.0-rc3-dirty gregkh#12 VOLUNTARY Hardware name: IBM pSeries (emulated by qemu) POWER8 (architected) 0x4d0200 0xf000004 of:SLOF,HEAD hv:linux,kvm pSeries NIP: c00000000015426c LR: c0000000001543b4 CTR: 0000000000000000 REGS: c0000000497c77e0 TRAP: 0700 Not tainted (6.16.0-rc3-dirty) MSR: 8000000002823033 <SF,VEC,VSX,FP,ME,IR,DR,RI,LE> CR: 28888482 XER: 00000000 CFAR: c0000000001543b0 IRQMASK: 3 <...> NIP [c00000000015426c] assert_slb_presence+0x2c/0x50 LR [c0000000001543b4] slb_insert_entry+0x124/0x390 Call Trace: 0x7fffceb5ffff (unreliable) preload_new_slb_context+0x100/0x1a0 start_thread+0x26c/0x420 load_elf_binary+0x1b04/0x1c40 bprm_execve+0x358/0x680 do_execveat_common+0x1f8/0x240 sys_execve+0x58/0x70 system_call_exception+0x114/0x300 system_call_common+0x160/0x2c4 >From the above analysis, during early exec the hardware SLB is cleared, and entries from the software preload cache are reloaded into hardware by switch_slb. However, preload_new_slb_context and slb_setup_new_exec also attempt to load some of the same entries, which can trigger a multi-hit. In most cases, these additional preloads simply hit existing entries and add nothing new. Removing these functions avoids redundant preloads and eliminates the multi-hit issue. This patch removes these two functions. We tested process switching performance using the context_switch benchmark on POWER9/hash, and observed no regression. Without this patch: 129041 ops/sec With this patch: 129341 ops/sec We also measured SLB faults during boot, and the counts are essentially the same with and without this patch. SLB faults without this patch: 19727 SLB faults with this patch: 19786 Fixes: 5434ae7 ("powerpc/64s/hash: Add a SLB preload cache") cc: [email protected] Suggested-by: Nicholas Piggin <[email protected]> Signed-off-by: Donet Tom <[email protected]> Signed-off-by: Ritesh Harjani (IBM) <[email protected]> Signed-off-by: Madhavan Srinivasan <[email protected]> Link: https://patch.msgid.link/0ac694ae683494fe8cadbd911a1a5018d5d3c541.1761834163.git.ritesh.list@gmail.com

commit 9d274c1 upstream. We have been seeing crashes on duplicate keys in btrfs_set_item_key_safe(): BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192) ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.c:2620! invalid opcode: 0000 [gregkh#1] PREEMPT SMP PTI CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 gregkh#6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs] With the following stack trace: #0 btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4) gregkh#1 btrfs_drop_extents (fs/btrfs/file.c:411:4) gregkh#2 log_one_extent (fs/btrfs/tree-log.c:4732:9) gregkh#3 btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9) gregkh#4 btrfs_log_inode (fs/btrfs/tree-log.c:6626:9) gregkh#5 btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8) gregkh#6 btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8) gregkh#7 btrfs_sync_file (fs/btrfs/file.c:1933:8) gregkh#8 vfs_fsync_range (fs/sync.c:188:9) gregkh#9 vfs_fsync (fs/sync.c:202:9) gregkh#10 do_fsync (fs/sync.c:212:9) gregkh#11 __do_sys_fdatasync (fs/sync.c:225:9) gregkh#12 __se_sys_fdatasync (fs/sync.c:223:1) gregkh#13 __x64_sys_fdatasync (fs/sync.c:223:1) gregkh#14 do_syscall_x64 (arch/x86/entry/common.c:52:14) gregkh#15 do_syscall_64 (arch/x86/entry/common.c:83:7) gregkh#16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121) So we're logging a changed extent from fsync, which is splitting an extent in the log tree. But this split part already exists in the tree, triggering the BUG(). This is the state of the log tree at the time of the crash, dumped with drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py) to get more details than btrfs_print_leaf() gives us: >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"]) leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610 leaf 33439744 flags 0x100000000000000 fs uuid e5bd3946-400c-4223-8923-190ef1f18677 chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160 generation 7 transid 9 size 8192 nbytes 8473563889606862198 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 204 flags 0x10(PREALLOC) atime 1716417703.220000000 (2024-05-22 15:41:43) ctime 1716417704.983333333 (2024-05-22 15:41:44) mtime 1716417704.983333333 (2024-05-22 15:41:44) otime 17592186044416.000000000 (559444-03-08 01:40:16) item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13 index 195 namelen 3 name: 193 item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37 location key (0 UNKNOWN.0 0) type XATTR transid 7 data_len 1 name_len 6 name: user.a data a item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53 generation 9 type 1 (regular) extent data disk byte 303144960 nr 12288 extent data offset 0 nr 4096 ram 12288 extent compression 0 (none) item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 4096 nr 8192 item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 8192 nr 4096 ... So the real problem happened earlier: notice that items 4 (4k-12k) and 5 (8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and item 5 starts at i_size. Here is the state of the filesystem tree at the time of the crash: >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0)) >>> print_extent_buffer(nodes[0]) leaf 30425088 level 0 items 184 generation 9 owner 5 leaf 30425088 flags 0x100000000000000 fs uuid e5bd3946-400c-4223-8923-190ef1f18677 chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da ... item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160 generation 7 transid 7 size 4096 nbytes 12288 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 6 flags 0x10(PREALLOC) atime 1716417703.220000000 (2024-05-22 15:41:43) ctime 1716417703.220000000 (2024-05-22 15:41:43) mtime 1716417703.220000000 (2024-05-22 15:41:43) otime 1716417703.220000000 (2024-05-22 15:41:43) item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13 index 195 namelen 3 name: 193 item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37 location key (0 UNKNOWN.0 0) type XATTR transid 7 data_len 1 name_len 6 name: user.a data a item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53 generation 9 type 1 (regular) extent data disk byte 303144960 nr 12288 extent data offset 0 nr 8192 ram 12288 extent compression 0 (none) item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 8192 nr 4096 Item 5 in the log tree corresponds to item 183 in the filesystem tree, but nothing matches item 4. Furthermore, item 183 is the last item in the leaf. btrfs_log_prealloc_extents() is responsible for logging prealloc extents beyond i_size. It first truncates any previously logged prealloc extents that start beyond i_size. Then, it walks the filesystem tree and copies the prealloc extent items to the log tree. If it hits the end of a leaf, then it calls btrfs_next_leaf(), which unlocks the tree and does another search. However, while the filesystem tree is unlocked, an ordered extent completion may modify the tree. In particular, it may insert an extent item that overlaps with an extent item that was already copied to the log tree. This may manifest in several ways depending on the exact scenario, including an EEXIST error that is silently translated to a full sync, overlapping items in the log tree, or this crash. This particular crash is triggered by the following sequence of events: - Initially, the file has i_size=4k, a regular extent from 0-4k, and a prealloc extent beyond i_size from 4k-12k. The prealloc extent item is the last item in its B-tree leaf. - The file is fsync'd, which copies its inode item and both extent items to the log tree. - An xattr is set on the file, which sets the BTRFS_INODE_COPY_EVERYTHING flag. - The range 4k-8k in the file is written using direct I/O. i_size is extended to 8k, but the ordered extent is still in flight. - The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this calls copy_inode_items_to_log(), which calls btrfs_log_prealloc_extents(). - btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the filesystem tree. Since it starts before i_size, it skips it. Since it is the last item in its B-tree leaf, it calls btrfs_next_leaf(). - btrfs_next_leaf() unlocks the path. - The ordered extent completion runs, which converts the 4k-8k part of the prealloc extent to written and inserts the remaining prealloc part from 8k-12k. - btrfs_next_leaf() does a search and finds the new prealloc extent 8k-12k. - btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into the log tree. Note that it overlaps with the 4k-12k prealloc extent that was copied to the log tree by the first fsync. - fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k extent that was written. - This tries to drop the range 4k-8k in the log tree, which requires adjusting the start of the 4k-12k prealloc extent in the log tree to 8k. - btrfs_set_item_key_safe() sees that there is already an extent starting at 8k in the log tree and calls BUG(). Fix this by detecting when we're about to insert an overlapping file extent item in the log tree and truncating the part that would overlap. CC: [email protected] # 6.1+ Reviewed-by: Filipe Manana <[email protected]> Signed-off-by: Omar Sandoval <[email protected]> Signed-off-by: David Sterba <[email protected]> Signed-off-by: Harshvardhan Jha <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

… 'T' When perf report with annotation for a symbol, press 's' and 'T', then exit the annotate browser. Once annotate the same symbol, the annotate browser will crash. The browser.arch was required to be correctly updated when data type feature was enabled by 'T'. Usually it was initialized by symbol__annotate2 function. If a symbol has already been correctly annotated at the first time, it should not call the symbol__annotate2 function again, thus the browser.arch will not get initialized. Then at the second time to show the annotate browser, the data type needs to be displayed but the browser.arch is empty. Stack trace as below: Perf: Segmentation fault -------- backtrace -------- #0 0x55d365 in ui__signal_backtrace setup.c:0 gregkh#1 0x7f5ff1a3e930 in __restore_rt libc.so.6[3e930] gregkh#2 0x570f08 in arch__is perf[570f08] gregkh#3 0x562186 in annotate_get_insn_location perf[562186] gregkh#4 0x562626 in __hist_entry__get_data_type annotate.c:0 gregkh#5 0x56476d in annotation_line__write perf[56476d] gregkh#6 0x54e2db in annotate_browser__write annotate.c:0 gregkh#7 0x54d061 in ui_browser__list_head_refresh perf[54d061] gregkh#8 0x54dc9e in annotate_browser__refresh annotate.c:0 gregkh#9 0x54c03d in __ui_browser__refresh browser.c:0 gregkh#10 0x54ccf8 in ui_browser__run perf[54ccf8] gregkh#11 0x54eb92 in __hist_entry__tui_annotate perf[54eb92] gregkh#12 0x552293 in do_annotate hists.c:0 gregkh#13 0x55941c in evsel__hists_browse hists.c:0 gregkh#14 0x55b00f in evlist__tui_browse_hists perf[55b00f] gregkh#15 0x42ff02 in cmd_report perf[42ff02] gregkh#16 0x494008 in run_builtin perf.c:0 gregkh#17 0x494305 in handle_internal_command perf.c:0 gregkh#18 0x410547 in main perf[410547] gregkh#19 0x7f5ff1a295d0 in __libc_start_call_main libc.so.6[295d0] gregkh#20 0x7f5ff1a29680 in __libc_start_main@@GLIBC_2.34 libc.so.6[29680] gregkh#21 0x410b75 in _start perf[410b75] Fixes: 1d4374a ("perf annotate: Add 'T' hot key to toggle data type display") Reviewed-by: James Clark <[email protected]> Tested-by: Namhyung Kim <[email protected]> Signed-off-by: Tianyou Li <[email protected]> Signed-off-by: Namhyung Kim <[email protected]>

When using perf record with the `--overwrite` option, a segmentation fault occurs if an event fails to open. For example: perf record -e cycles-ct -F 1000 -a --overwrite Error: cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' perf: Segmentation fault #0 0x6466b6 in dump_stack debug.c:366 gregkh#1 0x646729 in sighandler_dump_stack debug.c:378 gregkh#2 0x453fd1 in sigsegv_handler builtin-record.c:722 gregkh#3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090] gregkh#4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862 gregkh#5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943 gregkh#6 0x458090 in record__synthesize builtin-record.c:2075 gregkh#7 0x45a85a in __cmd_record builtin-record.c:2888 gregkh#8 0x45deb6 in cmd_record builtin-record.c:4374 gregkh#9 0x4e5e33 in run_builtin perf.c:349 gregkh#10 0x4e60bf in handle_internal_command perf.c:401 gregkh#11 0x4e6215 in run_argv perf.c:448 gregkh#12 0x4e653a in main perf.c:555 gregkh#13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72] gregkh#14 0x43a3ee in _start ??:0 The --overwrite option implies --tail-synthesize, which collects non-sample events reflecting the system status when recording finishes. However, when evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist is not initialized and remains NULL. The code unconditionally calls record__synthesize() in the error path, which iterates through the NULL evlist pointer and causes a segfault. To fix it, move the record__synthesize() call inside the error check block, so it's only called when there was no error during recording, ensuring that evlist is properly initialized. Fixes: 4ea648a ("perf record: Add --tail-synthesize option") Signed-off-by: Shuai Xue <[email protected]> Signed-off-by: Namhyung Kim <[email protected]>

[ Upstream commit 163e5f2 ] When using perf record with the `--overwrite` option, a segmentation fault occurs if an event fails to open. For example: perf record -e cycles-ct -F 1000 -a --overwrite Error: cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' perf: Segmentation fault #0 0x6466b6 in dump_stack debug.c:366 gregkh#1 0x646729 in sighandler_dump_stack debug.c:378 gregkh#2 0x453fd1 in sigsegv_handler builtin-record.c:722 gregkh#3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090] gregkh#4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862 gregkh#5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943 gregkh#6 0x458090 in record__synthesize builtin-record.c:2075 gregkh#7 0x45a85a in __cmd_record builtin-record.c:2888 gregkh#8 0x45deb6 in cmd_record builtin-record.c:4374 gregkh#9 0x4e5e33 in run_builtin perf.c:349 gregkh#10 0x4e60bf in handle_internal_command perf.c:401 gregkh#11 0x4e6215 in run_argv perf.c:448 gregkh#12 0x4e653a in main perf.c:555 gregkh#13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72] gregkh#14 0x43a3ee in _start ??:0 The --overwrite option implies --tail-synthesize, which collects non-sample events reflecting the system status when recording finishes. However, when evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist is not initialized and remains NULL. The code unconditionally calls record__synthesize() in the error path, which iterates through the NULL evlist pointer and causes a segfault. To fix it, move the record__synthesize() call inside the error check block, so it's only called when there was no error during recording, ensuring that evlist is properly initialized. Fixes: 4ea648a ("perf record: Add --tail-synthesize option") Signed-off-by: Shuai Xue <[email protected]> Signed-off-by: Namhyung Kim <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

[ Upstream commit 163e5f2 ] When using perf record with the `--overwrite` option, a segmentation fault occurs if an event fails to open. For example: perf record -e cycles-ct -F 1000 -a --overwrite Error: cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' perf: Segmentation fault #0 0x6466b6 in dump_stack debug.c:366 #1 0x646729 in sighandler_dump_stack debug.c:378 #2 0x453fd1 in sigsegv_handler builtin-record.c:722 #3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090] #4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862 #5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943 #6 0x458090 in record__synthesize builtin-record.c:2075 #7 0x45a85a in __cmd_record builtin-record.c:2888 #8 0x45deb6 in cmd_record builtin-record.c:4374 #9 0x4e5e33 in run_builtin perf.c:349 #10 0x4e60bf in handle_internal_command perf.c:401 #11 0x4e6215 in run_argv perf.c:448 #12 0x4e653a in main perf.c:555 #13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72] #14 0x43a3ee in _start ??:0 The --overwrite option implies --tail-synthesize, which collects non-sample events reflecting the system status when recording finishes. However, when evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist is not initialized and remains NULL. The code unconditionally calls record__synthesize() in the error path, which iterates through the NULL evlist pointer and causes a segfault. To fix it, move the record__synthesize() call inside the error check block, so it's only called when there was no error during recording, ensuring that evlist is properly initialized. Fixes: 4ea648a ("perf record: Add --tail-synthesize option") Signed-off-by: Shuai Xue <[email protected]> Signed-off-by: Namhyung Kim <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

Update dh.c

0956506

here, converting bytes to u64, we need to right shift 3, not 6.

gregkh closed this Feb 13, 2024

imaami pushed a commit to imaami/linux that referenced this pull request Apr 20, 2024

sched/alt: Fix limited cpufreq for schedutil.

327100b

Here is the first fix for gregkh#12, which fix the limited cpufreq for schedutil. But it still tend to stay at max cpufreq.

luc14n0 pushed a commit to luc14n0/openSUSE-kernel that referenced this pull request Apr 23, 2024

sched/alt: Fix limited cpufreq for schedutil.

7ff5906

Here is the first fix for gregkh#12, which fix the limited cpufreq for schedutil. But it still tend to stay at max cpufreq.

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Update dh.c #12

Update dh.c #12

Uh oh!

HelenHZhang commented Feb 12, 2024 •

edited

Loading

Uh oh!

HelenHZhang commented Feb 13, 2024

Uh oh!

gregkh commented Feb 13, 2024

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

Update dh.c #12

Update dh.c #12

Uh oh!

Conversation

HelenHZhang commented Feb 12, 2024 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

HelenHZhang commented Feb 13, 2024

Uh oh!

gregkh commented Feb 13, 2024

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

HelenHZhang commented Feb 12, 2024 •

edited

Loading