bpf: Fix pcap filter bypass with --filter-trace-xdp and --filter-track-skb#635
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jschwinger233 merged 1 commit intomainfrom Jan 1, 2026
Merged
bpf: Fix pcap filter bypass with --filter-trace-xdp and --filter-track-skb#635jschwinger233 merged 1 commit intomainfrom
jschwinger233 merged 1 commit intomainfrom
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…k-skb When both flags are enabled (need to trace XDP programs), fexit/xdp unconditionally tracked all XDP packets for later SKB tracing, causing the pcap filter to be bypassed. Fix by adding a per-CPU boolean map to pass filter match status from fentry/xdp to fexit/xdp, so only filtered packets are tracked. Signed-off-by: Martynas Pumputis <[email protected]>
jschwinger233
approved these changes
Jan 1, 2026
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When both flags are enabled (need to trace XDP programs), fexit/xdp unconditionally tracked all XDP packets for later SKB tracing, causing the pcap filter to be bypassed.
Fix by adding a per-CPU boolean map to pass filter match status from fentry/xdp to fexit/xdp, so only filtered packets are tracked.
Fix #445.