diff options
3 files changed, 29 insertions, 0 deletions
diff --git a/compiler-rt/include/sanitizer/common_interface_defs.h b/compiler-rt/include/sanitizer/common_interface_defs.h index ef645e52711..47df81b68dd 100644 --- a/compiler-rt/include/sanitizer/common_interface_defs.h +++ b/compiler-rt/include/sanitizer/common_interface_defs.h @@ -111,6 +111,15 @@ extern "C" { // Sets the callback to be called right before death on error. // Passing 0 will unset the callback. void __sanitizer_set_death_callback(void (*callback)(void)); + + // Interceptor hooks. + // Whenever a libc function interceptor is called it checks if the + // corresponding weak hook is defined, and it so -- calls it. + // The primary use case is data-flow-guided fuzzing, where the fuzzer needs + // to know what is being passed to libc functions, e.g. memcmp. + // FIXME: implement more hooks. + void __sanitizer_weak_hook_memcmp(void *called_pc, const void *s1, + const void *s2, size_t n); #ifdef __cplusplus } // extern "C" #endif diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc index b14dce62a9e..f5e96708cfe 100644 --- a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc +++ b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc @@ -39,6 +39,16 @@ #include <stdarg.h> +#if SANITIZER_INTERCEPTOR_HOOKS +#define CALL_WEAK_INTERCEPTOR_HOOK4(f, ...) \ + do { \ + if (f) \ + f(__VA_ARGS__); \ + } while (false); +#else +#define CALL_WEAK_INTERCEPTOR_HOOK4(f, a1, a2, a3, a4) +#endif // SANITIZER_INTERCEPTOR_HOOKS + #if SANITIZER_WINDOWS && !defined(va_copy) #define va_copy(dst, src) ((dst) = (src)) #endif // _WIN32 @@ -363,11 +373,20 @@ INTERCEPTOR(char *, strpbrk, const char *s1, const char *s2) { #endif #if SANITIZER_INTERCEPT_MEMCMP + +extern "C" { +SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE +void __sanitizer_weak_hook_memcmp(uptr called_pc, const void *s1, + const void *s2, uptr n); +} // extern "C" + INTERCEPTOR(int, memcmp, const void *a1, const void *a2, uptr size) { void *ctx; COMMON_INTERCEPTOR_ENTER(ctx, memcmp, a1, a2, size); if (COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED) return internal_memcmp(a1, a2, size); + CALL_WEAK_INTERCEPTOR_HOOK4(__sanitizer_weak_hook_memcmp, GET_CALLER_PC(), a1, + a2, size); if (common_flags()->intercept_memcmp) { if (common_flags()->strict_memcmp) { // Check the entire regions even if the first bytes of the buffers are diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h index 52886b6ee91..a666b252827 100644 --- a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h +++ b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h @@ -254,5 +254,6 @@ #define SANITIZER_INTERCEPT_MLOCKX SI_NOT_WINDOWS #define SANITIZER_INTERCEPT_FOPENCOOKIE SI_LINUX_NOT_ANDROID +#define SANITIZER_INTERCEPTOR_HOOKS SI_LINUX #endif // #ifndef SANITIZER_PLATFORM_INTERCEPTORS_H |
