Reland "[compiler-rt] Intercept the bcmp() function."

Fix test issues on darwin: The REQUIRES for the test should be the same as the
guard for whether we intercept bcmp.

llvm-svn: 355204

compiler-rt/lib/asan/tests/asan_mem_test.cc

@@ -9,7 +9,11 @@
 // This file is a part of AddressSanitizer, an address sanity checker.
 //
 //===----------------------------------------------------------------------===//
+#include <string.h>
 #include "asan_test_utils.h"
+#if defined(_GNU_SOURCE)
+#include <strings.h>  // for bcmp
+#endif
 #include <vector>
 
 template<typename T>
@@ -205,37 +209,43 @@ TEST(AddressSanitizer, MemMoveOOBTest) {
   MemTransferOOBTestTemplate<int, MemMoveWrapper>(1024);
 }
 
-
-TEST(AddressSanitizer, MemCmpOOBTest) {
+template <int (*cmpfn)(const void *, const void *, size_t)>
+void CmpOOBTestCommon() {
   size_t size = Ident(100);
   char *s1 = MallocAndMemsetString(size);
   char *s2 = MallocAndMemsetString(size);
-  // Normal memcmp calls.
-  Ident(memcmp(s1, s2, size));
-  Ident(memcmp(s1 + size - 1, s2 + size - 1, 1));
-  Ident(memcmp(s1 - 1, s2 - 1, 0));
+  // Normal cmpfn calls.
+  Ident(cmpfn(s1, s2, size));
+  Ident(cmpfn(s1 + size - 1, s2 + size - 1, 1));
+  Ident(cmpfn(s1 - 1, s2 - 1, 0));
   // One of arguments points to not allocated memory.
-  EXPECT_DEATH(Ident(memcmp)(s1 - 1, s2, 1), LeftOOBReadMessage(1));
-  EXPECT_DEATH(Ident(memcmp)(s1, s2 - 1, 1), LeftOOBReadMessage(1));
-  EXPECT_DEATH(Ident(memcmp)(s1 + size, s2, 1), RightOOBReadMessage(0));
-  EXPECT_DEATH(Ident(memcmp)(s1, s2 + size, 1), RightOOBReadMessage(0));
+  EXPECT_DEATH(Ident(cmpfn)(s1 - 1, s2, 1), LeftOOBReadMessage(1));
+  EXPECT_DEATH(Ident(cmpfn)(s1, s2 - 1, 1), LeftOOBReadMessage(1));
+  EXPECT_DEATH(Ident(cmpfn)(s1 + size, s2, 1), RightOOBReadMessage(0));
+  EXPECT_DEATH(Ident(cmpfn)(s1, s2 + size, 1), RightOOBReadMessage(0));
   // Hit unallocated memory and die.
-  EXPECT_DEATH(Ident(memcmp)(s1 + 1, s2 + 1, size), RightOOBReadMessage(0));
-  EXPECT_DEATH(Ident(memcmp)(s1 + size - 1, s2, 2), RightOOBReadMessage(0));
+  EXPECT_DEATH(Ident(cmpfn)(s1 + 1, s2 + 1, size), RightOOBReadMessage(0));
+  EXPECT_DEATH(Ident(cmpfn)(s1 + size - 1, s2, 2), RightOOBReadMessage(0));
   // Zero bytes are not terminators and don't prevent from OOB.
   s1[size - 1] = '\0';
   s2[size - 1] = '\0';
-  EXPECT_DEATH(Ident(memcmp)(s1, s2, size + 1), RightOOBReadMessage(0));
+  EXPECT_DEATH(Ident(cmpfn)(s1, s2, size + 1), RightOOBReadMessage(0));
 
   // Even if the buffers differ in the first byte, we still assume that
-  // memcmp may access the whole buffer and thus reporting the overflow here:
+  // cmpfn may access the whole buffer and thus reporting the overflow here:
   s1[0] = 1;
   s2[0] = 123;
-  EXPECT_DEATH(Ident(memcmp)(s1, s2, size + 1), RightOOBReadMessage(0));
+  EXPECT_DEATH(Ident(cmpfn)(s1, s2, size + 1), RightOOBReadMessage(0));
 
   free(s1);
   free(s2);
 }
 
+TEST(AddressSanitizer, MemCmpOOBTest) { CmpOOBTestCommon<memcmp>(); }
 
-
+TEST(AddressSanitizer, BCmpOOBTest) {
+#if (defined(__linux__) && !defined(__ANDROID__) && defined(_GNU_SOURCE)) || \
+    defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
+  CmpOOBTestCommon<bcmp>();
+#endif
+}

compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc

@@ -819,16 +819,14 @@ INTERCEPTOR(void *, memcpy, void *dst, const void *src, uptr size) {
 #endif
 
 #if SANITIZER_INTERCEPT_MEMCMP
-
 DECLARE_WEAK_INTERCEPTOR_HOOK(__sanitizer_weak_hook_memcmp, uptr called_pc,
                               const void *s1, const void *s2, uptr n,
                               int result)
 
-INTERCEPTOR(int, memcmp, const void *a1, const void *a2, uptr size) {
-  if (COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED)
-    return internal_memcmp(a1, a2, size);
-  void *ctx;
-  COMMON_INTERCEPTOR_ENTER(ctx, memcmp, a1, a2, size);
+// Common code for `memcmp` and `bcmp`.
+int MemcmpInterceptorCommon(void *ctx,
+                            int (*real_fn)(const void *, const void *, uptr),
+                            const void *a1, const void *a2, uptr size) {
   if (common_flags()->intercept_memcmp) {
     if (common_flags()->strict_memcmp) {
       // Check the entire regions even if the first bytes of the buffers are
@@ -854,17 +852,39 @@ INTERCEPTOR(int, memcmp, const void *a1, const void *a2, uptr size) {
       return r;
     }
   }
-  int result = REAL(memcmp(a1, a2, size));
+  int result = real_fn(a1, a2, size);
   CALL_WEAK_INTERCEPTOR_HOOK(__sanitizer_weak_hook_memcmp, GET_CALLER_PC(), a1,
                              a2, size, result);
   return result;
 }
 
+INTERCEPTOR(int, memcmp, const void *a1, const void *a2, uptr size) {
+  if (COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED)
+    return internal_memcmp(a1, a2, size);
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, memcmp, a1, a2, size);
+  return MemcmpInterceptorCommon(ctx, REAL(memcmp), a1, a2, size);
+}
+
 #define INIT_MEMCMP COMMON_INTERCEPT_FUNCTION(memcmp)
 #else
 #define INIT_MEMCMP
 #endif
 
+#if SANITIZER_INTERCEPT_BCMP
+INTERCEPTOR(int, bcmp, const void *a1, const void *a2, uptr size) {
+  if (COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED)
+    return internal_memcmp(a1, a2, size);
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, bcmp, a1, a2, size);
+  return MemcmpInterceptorCommon(ctx, REAL(bcmp), a1, a2, size);
+}
+
+#define INIT_BCMP COMMON_INTERCEPT_FUNCTION(bcmp)
+#else
+#define INIT_BCMP
+#endif
+
 #if SANITIZER_INTERCEPT_MEMCHR
 INTERCEPTOR(void*, memchr, const void *s, int c, SIZE_T n) {
   if (COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED)
@@ -9492,6 +9512,7 @@ static void InitializeCommonInterceptors() {
   INIT_MEMCPY;
   INIT_MEMCHR;
   INIT_MEMCMP;
+  INIT_BCMP;
   INIT_MEMRCHR;
   INIT_MEMMEM;
   INIT_READ;

compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h

@@ -142,6 +142,9 @@
 #define SANITIZER_INTERCEPT_MEMMOVE 1
 #define SANITIZER_INTERCEPT_MEMCPY 1
 #define SANITIZER_INTERCEPT_MEMCMP SI_NOT_FUCHSIA
+#define SANITIZER_INTERCEPT_BCMP \
+  SANITIZER_INTERCEPT_MEMCMP &&  \
+      ((SI_POSIX && _GNU_SOURCE) || SI_NETBSD || SI_OPENBSD || SI_FREEBSD)
 #define SANITIZER_INTERCEPT_STRNDUP SI_POSIX
 #define SANITIZER_INTERCEPT___STRNDUP SI_LINUX_NOT_FREEBSD
 #if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \

compiler-rt/test/asan/TestCases/Posix/bcmp_test.cc

@@ -0,0 +1,18 @@
+// RUN: %clangxx_asan -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_asan -O1 %s -o %t && not %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_asan -O2 %s -o %t && not %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_asan -O3 %s -o %t && not %run %t 2>&1 | FileCheck %s
+
+// REQUIRES: compiler-rt-optimized, (linux && !android) || openbsd || freebsd || netbsd 
+// XFAIL: darwin
+
+#include <string.h>
+int main(int argc, char **argv) {
+  char a1[] = {static_cast<char>(argc), 2, 3, 4};
+  char a2[] = {1, static_cast<char>(2 * argc), 3, 4};
+  int res = bcmp(a1, a2, 4 + argc); // BOOM
+  // CHECK: AddressSanitizer: stack-buffer-overflow
+  // CHECK: {{#1.*bcmp}}
+  // CHECK: {{#2.*main}}
+  return res;
+}

compiler-rt/test/asan/TestCases/memcmp_test.cc

@@ -11,7 +11,7 @@ int main(int argc, char **argv) {
   char a2[] = {1, static_cast<char>(2*argc), 3, 4};
   int res = memcmp(a1, a2, 4 + argc);  // BOOM
   // CHECK: AddressSanitizer: stack-buffer-overflow
-  // CHECK: {{#0.*memcmp}}
-  // CHECK: {{#1.*main}}
+  // CHECK: {{#1.*memcmp}}
+  // CHECK: {{#2.*main}}
   return res;
 }

compiler-rt/test/msan/memcmp_test.cc

@@ -13,6 +13,6 @@ int main(int argc, char **argv) {
   if (!res)
     printf("equals");
   return 0;
-  // CHECK: Uninitialized bytes in __interceptor_memcmp at offset 3
+  // CHECK: Uninitialized bytes in MemcmpInterceptorCommon at offset 3
   // CHECK: MemorySanitizer: use-of-uninitialized-value
 }

compiler-rt/test/msan/scoped-interceptors.cc

@@ -37,7 +37,7 @@ int main(int argc, char *argv[]) {
     case '2': {
       int cmp = memcmp(uninit, uninit, sizeof(uninit));  // BOOM
       break;
-      // CASE-2: Uninitialized bytes in __interceptor_memcmp
+      // CASE-2: Uninitialized bytes in MemcmpInterceptorCommon
     }
     case '3': {
       size_t len = strlen(uninit);  // BOOM

compiler-rt/test/sanitizer_common/TestCases/Posix/weak_hook_test.cc

@@ -6,8 +6,11 @@
 // XFAIL: lsan
 // XFAIL: ubsan
 
-#include <string.h>
 #include <assert.h>
+#include <string.h>
+#if defined(_GNU_SOURCE)
+#include <strings.h> // for bcmp
+#endif
 
 bool seen_memcmp, seen_strncmp, seen_strncasecmp, seen_strcmp, seen_strcasecmp,
     seen_strstr, seen_strcasestr, seen_memmem;
@@ -59,6 +62,12 @@ int main() {
   int_sink = memcmp(s1, s2, sizeof(s2));
   assert(seen_memcmp);
 
+#if (defined(__linux__) && !defined(__ANDROID__) && defined(_GNU_SOURCE)) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
+  seen_memcmp = false;
+  int_sink = bcmp(s1, s2, sizeof(s2));
+  assert(seen_memcmp);
+#endif
+
   int_sink = strncmp(s1, s2, sizeof(s2));
   assert(seen_strncmp);