[PATCH] D63841: [GWP-ASan] Add generic unwinders and structure backtrace output.

Wed Jun 26 13:47:21 PDT 2019

hctim added a comment.

The new output format using the libc based unwinder is below. The report can be symbolized properly by using addr2line, but we don't really want to fork/exec during crash handling for obvious reasons. The libc generic unwinder provides either a function offset or a binary offset, so they can be happily symbolized offline.

The sanitizer unwinder does a better job of symbolizing online.

  *** GWP-ASan detected a memory error ***
  Use after free at 0xf7f22ff0 (0 bytes into a 10-byte allocation at 0xf7f22ff0) by thread 171092 here:
    #0 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(_ZN8gwp_asan20GuardedPoolAllocator19reportErrorInternalEjNS0_5ErrorE+0x3c8) [0x5660a4b8]
    #1 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(_ZN8gwp_asan20GuardedPoolAllocator11reportErrorEjNS0_5ErrorE+0x2a) [0x5660a03a]
    #2 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(+0x1877e) [0x5660977e]
    #3 linux-gate.so.1(__kernel_rt_sigreturn+0) [0xf7f4b0a0]
    #4 /lib/i386-linux-gnu/libc.so.6(__libc_start_main+0xf1) [0xf7a8d4f1]

  0xf7f22ff0 was allocated by thread 171092 here:
    #0 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(_ZN8gwp_asan20GuardedPoolAllocator8allocateEj+0x1b9) [0x56609ce9]
    #1 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(+0x27c8e) [0x56618c8e]
    #2 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(+0x278ed) [0x566188ed]
    #3 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(malloc+0x20) [0x5661bee0]
    #4 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(main+0x2b) [0x5661de6b]
    #5 /lib/i386-linux-gnu/libc.so.6(__libc_start_main+0xf1) [0xf7a8d4f1]

  0xf7f22ff0 was deallocated by thread 171092 here:
    #0 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(_ZN8gwp_asan20GuardedPoolAllocator10deallocateEPv+0xb6) [0x56609f16]
    #1 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(+0x27f91) [0x56618f91]
    #2 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(+0x27e1e) [0x56618e1e]
    #3 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(cfree+0x1f) [0x5661beaf]
    #4 ./projects/compiler-rt/test/gwp_asan/I386LinuxConfig/Output/use_after_free.cpp.tmp(main+0x65) [0x5661dea5]
    #5 /lib/i386-linux-gnu/libc.so.6(__libc_start_main+0xf1) [0xf7a8d4f1]

  *** End GWP-ASan report ***

Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D63841/new/

https://reviews.llvm.org/D63841