compiler-rt/test/asan/TestCases/Linux/segv_read_write.c

   1 // RUN: %clangxx_asan -std=c++11 -O0 %s -o %t
   2 // RUN: not %run %t       2>&1 | FileCheck %s --check-prefix=READ
   3 // RUN: not %run %t write 2>&1 | FileCheck %s --check-prefix=WRITE
   4 // UNSUPPORTED: target={{(powerpc64|mips|s390).*}}
   5
   6 #include <sys/mman.h>
   7
   8 static volatile int sink;
   9 __attribute__((noinline)) void Read(int *ptr) { sink = *ptr; }
  10 __attribute__((noinline)) void Write(int *ptr) { *ptr = 0; }
  11 int main(int argc, char **argv) {
  12   // Writes to shadow are detected as reads from shadow gap (because of how the
  13   // shadow mapping works). This is kinda hard to fix. Test a random address in
  14   // the application part of the address space.
  15   void *volatile p =
  16       mmap(nullptr, 4096, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
  17   munmap(p, 4096);
  18   if (argc == 1)
  19     Read((int *)p);
  20   else
  21     Write((int *)p);
  22 }
  23 // READ: AddressSanitizer: SEGV on unknown address
  24 // READ: The signal is caused by a READ memory access.
  25 // WRITE: AddressSanitizer: SEGV on unknown address
  26 // WRITE: The signal is caused by a WRITE memory access.