replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[sanitizers] read/write page fault detection on mac. 

Summary: Resubmit of http://reviews.llvm.org/D19495 enabled only on intel.

Subscribers: kubabrecka

Differential Revision: http://reviews.llvm.org/D19561

llvm-svn: 267750
This commit is contained in:
Mike Aizatsky 2016-04-27 18:02:21 +00:00
parent 2eabf2484f
commit ccd318dc7e
2 changed files with 32 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
compiler-rt/lib/sanitizer_common/sanitizer_mac.cc
View File

@ -506,7 +506,12 @@ void LogFullErrorReport(const char *buffer) {
}
SignalContext::WriteFlag SignalContext::GetWriteFlag(void *context) {
return UNKNOWN; // FIXME: implement this.
#if defined(__x86_64__) || defined(__i386__)
ucontext_t *ucontext = static_cast<ucontext_t*>(context);
return ucontext->uc_mcontext->__es.__err & 2 /*T_PF_WRITE*/ ? WRITE : READ;
#else
return UNKNOWN;
#endif
}
void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {

26
compiler-rt/test/asan/TestCases/Darwin/segv_read_write.c Normal file
View File

@ -0,0 +1,26 @@
// RUN: %clangxx_asan -std=c++11 -O0 %s -o %t
// RUN: not %run %t 2>&1 | FileCheck %s --check-prefix=READ
// RUN: not %run %t write 2>&1 | FileCheck %s --check-prefix=WRITE
// REQUIRES: x86-target-arch
#include <sys/mman.h>
static volatile int sink;
__attribute__((noinline)) void Read(int *ptr) { sink = *ptr; }
__attribute__((noinline)) void Write(int *ptr) { *ptr = 0; }
int main(int argc, char **argv) {
// Writes to shadow are detected as reads from shadow gap (because of how the
// shadow mapping works). This is kinda hard to fix. Test a random address in
// the application part of the address space.
void *volatile p =
mmap(nullptr, 4096, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
munmap(p, 4096);
if (argc == 1)
Read((int *)p);
else
Write((int *)p);
}
// READ: AddressSanitizer: SEGV on unknown address
// READ: The signal is caused by a READ memory access.
// WRITE: AddressSanitizer: SEGV on unknown address
// WRITE: The signal is caused by a WRITE memory access.