compiler-rt/test/asan/TestCases/strncpy-overflow.cpp

   1 // RUN: %clangxx_asan -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s
   2 // RUN: %clangxx_asan -O1 %s -o %t && not %run %t 2>&1 | FileCheck %s
   3 // RUN: %clangxx_asan -O2 %s -o %t && not %run %t 2>&1 | FileCheck %s
   4 // RUN: %clangxx_asan -O3 %s -o %t && not %run %t 2>&1 | FileCheck %s
   5
   6 // REQUIRES: compiler-rt-optimized
   7 // REQUIRES: stable-runtime
   8
   9 #include <string.h>
  10 #include <stdlib.h>
  11
  12 // We need a way to prevent the optimize from eliminating the
  13 // strncpy below (which otherwises writes to dead storage).  We
  14 // need the read to be out-of-line to prevent memory forwarding
  15 // from making the memory dead again.
  16 int sink_memory(int N, char *p) __attribute__((noinline));
  17 int sink_memory(int N, char *p) {
  18   int sum = 0;
  19   for (int i = 0; i < N; i++)
  20     sum += p[i];
  21   return sum;
  22 }
  23
  24 int main(int argc, char **argv) {
  25   char *hello = (char*)malloc(6);
  26   strcpy(hello, "hello");
  27   int rval = sink_memory(6, hello);
  28   char *short_buffer = (char*)malloc(9);
  29   strncpy(short_buffer, hello, 10);  // BOOM
  30   // CHECK: {{WRITE of size 10 at 0x.* thread T0}}
  31   // CHECK: {{    #0 0x.* in .*strncpy}}
  32   // CHECK: {{    #1 0x.* in main .*strncpy-overflow.cpp:}}[[@LINE-3]]
  33   // CHECK: {{0x.* is located 0 bytes after 9-byte region}}
  34   // CHECK: {{allocated by thread T0 here:}}
  35   // CHECK: {{    #0 0x.* in .*malloc}}
  36   // CHECK: {{    #[1-3] 0x.* in main .*strncpy-overflow.cpp:}}[[@LINE-8]]
  37   return rval + sink_memory(9, short_buffer);
  38 }