Fix detection of interfering branches for syscall at end of patch#3579
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rocallahan merged 1 commit intomasterfrom Aug 19, 2023
Merged
Fix detection of interfering branches for syscall at end of patch#3579rocallahan merged 1 commit intomasterfrom
rocallahan merged 1 commit intomasterfrom
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rocallahan
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Aug 19, 2023
src/Monkeypatcher.cc
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| found_potential_interfering_branch = true; | ||
| break; | ||
| if (hook.flags & PATCH_SYSCALL_INSTRUCTION_IS_LAST) { | ||
| if (!(hook.flags & PATCH_IS_MULTIPLE_INSTRUCTIONS)) { |
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Let's remove the ! by swapping the if/else blocks
…S_LAST The interfering branch check was assuming that the syscall (or rdtsc instruction) is at the start of the patch region. As a result, it was incorrectly ignoring interfering branches for PATCH_SYSCALL_INSTRUCTION_IS_LAST hooks (as well as detecting interfering branches that actually do not interfere).
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The interfering branch check was assuming that the syscall (or rdtsc instruction) is at the start of the patch region. As a result, it was incorrectly ignoring interfering branches for
PATCH_SYSCALL_INSTRUCTION_IS_LAST hooks (as well as detecting interfering branches that actually do not interfere).