[compiler-rt] r250761 - [msan] Intercept mincore.

[Evgeniy Stepanov via llvm-commits]

Author: eugenis
Date: Mon Oct 19 18:39:11 2015
New Revision: 250761

URL: http://llvm.org/viewvc/llvm-project?rev=250761&view=rev
Log:
[msan] Intercept mincore.

Added:
    compiler-rt/trunk/test/msan/Linux/mincore.cc
Modified:
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc?rev=250761&r1=250760&r2=250761&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_interceptors.inc Mon Oct 19 18:39:11 2015
@@ -5219,6 +5219,23 @@ INTERCEPTOR(int, pthread_setcanceltype,
 #define INIT_PTHREAD_SETCANCEL
 #endif
 
+#if SANITIZER_INTERCEPT_MINCORE
+INTERCEPTOR(int, mincore, void *addr, uptr length, unsigned char *vec) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, mincore, addr, length, vec);
+  int res = REAL(mincore)(addr, length, vec);
+  if (res == 0) {
+    uptr page_size = GetPageSizeCached();
+    uptr vec_size = ((length + page_size - 1) & (~(page_size - 1))) / page_size;
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, vec, vec_size);
+  }
+  return res;
+}
+#define INIT_MINCORE COMMON_INTERCEPT_FUNCTION(mincore);
+#else
+#define INIT_MINCORE
+#endif
+
 static void InitializeCommonInterceptors() {
   static u64 metadata_mem[sizeof(MetadataHashMap) / sizeof(u64) + 1];
   interceptor_metadata_map = new((void *)&metadata_mem) MetadataHashMap();
@@ -5391,4 +5408,5 @@ static void InitializeCommonInterceptors
   INIT_FOPENCOOKIE;
   INIT_SEM;
   INIT_PTHREAD_SETCANCEL;
+  INIT_MINCORE;
 }

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h?rev=250761&r1=250760&r2=250761&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_platform_interceptors.h Mon Oct 19 18:39:11 2015
@@ -258,6 +258,7 @@
 #define SANITIZER_INTERCEPT_FOPENCOOKIE SI_LINUX_NOT_ANDROID
 #define SANITIZER_INTERCEPT_SEM SI_LINUX || SI_FREEBSD
 #define SANITIZER_INTERCEPT_PTHREAD_SETCANCEL SI_NOT_WINDOWS
+#define SANITIZER_INTERCEPT_MINCORE SI_LINUX
 
 #define SANITIZER_INTERCEPTOR_HOOKS SI_LINUX
 

Added: compiler-rt/trunk/test/msan/Linux/mincore.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/msan/Linux/mincore.cc?rev=250761&view=auto
==============================================================================
--- compiler-rt/trunk/test/msan/Linux/mincore.cc (added)
+++ compiler-rt/trunk/test/msan/Linux/mincore.cc Mon Oct 19 18:39:11 2015
@@ -0,0 +1,36 @@
+// RUN: %clangxx_msan -std=c++11 -O0 %s -o %t && %run %t
+
+#include <assert.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sanitizer/msan_interface.h>
+
+int main(void) {
+  unsigned char vec[20];
+  int res;
+  size_t PS = sysconf(_SC_PAGESIZE);
+  void *addr = mmap(nullptr, 20 * PS, PROT_READ | PROT_WRITE,
+                    MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+
+  __msan_poison(&vec, sizeof(vec));
+  res = mincore(addr, 10 * PS, vec);
+  assert(res == 0);
+  assert(__msan_test_shadow(vec, sizeof(vec)) == 10);
+
+  __msan_poison(&vec, sizeof(vec));
+  res = mincore(addr, 10 * PS + 42, vec);
+  assert(res == 0);
+  assert(__msan_test_shadow(vec, sizeof(vec)) == 11);
+
+  __msan_poison(&vec, sizeof(vec));
+  res = mincore(addr, 10 * PS - 1, vec);
+  assert(res == 0);
+  assert(__msan_test_shadow(vec, sizeof(vec)) == 10);
+
+  __msan_poison(&vec, sizeof(vec));
+  res = mincore(addr, 1, vec);
+  assert(res == 0);
+  assert(__msan_test_shadow(vec, sizeof(vec)) == 1);
+
+  return 0;
+}