Report("WARNING: strchr* interceptors are enabled even though "
"replace_str=0. Use intercept_strchr=0 to disable them.");
}
+ if (!f->replace_str && common_flags()->intercept_strndup) {
+ Report("WARNING: strndup* interceptors are enabled even though "
+ "replace_str=0. Use intercept_strndup=0 to disable them.");
+ }
}
} // namespace __asan
free(str);
}
+#if SANITIZER_TEST_HAS_STRNDUP
+TEST(AddressSanitizer, MAYBE_StrNDupOOBTest) {
+ size_t size = Ident(42);
+ char *str = MallocAndMemsetString(size);
+ char *new_str;
+ // Normal strndup calls.
+ str[size - 1] = '\0';
+ new_str = strndup(str, size - 13);
+ free(new_str);
+ new_str = strndup(str + size - 1, 13);
+ free(new_str);
+ // Argument points to not allocated memory.
+ EXPECT_DEATH(Ident(strndup(str - 1, 13)), LeftOOBReadMessage(1));
+ EXPECT_DEATH(Ident(strndup(str + size, 13)), RightOOBReadMessage(0));
+ // Overwrite the terminating '\0' and hit unallocated memory.
+ str[size - 1] = 'z';
+ EXPECT_DEATH(Ident(strndup(str, size + 13)), RightOOBReadMessage(0));
+ free(str);
+}
+#endif // SANITIZER_TEST_HAS_STRNDUP
+
TEST(AddressSanitizer, StrCpyOOBTest) {
size_t to_size = Ident(30);
size_t from_size = Ident(6); // less than to_size
// Get the per-platform defines for what is possible to intercept
#include "sanitizer_common/sanitizer_platform_interceptors.h"
+DECLARE_REAL_AND_INTERCEPTOR(void *, malloc, uptr)
+
// TODO(bruening): tsan disables several interceptors (getpwent, etc.) claiming
// that interception is a perf hit: should we do the same?
#define MSAN_MAYBE_INTERCEPT___STRDUP
#endif
-INTERCEPTOR(char *, strndup, char *src, SIZE_T n) {
- ENSURE_MSAN_INITED();
- GET_STORE_STACK_TRACE;
- // On FreeBSD strndup() leverages strnlen().
- InterceptorScope interceptor_scope;
- SIZE_T copy_size = REAL(strnlen)(src, n);
- char *res = REAL(strndup)(src, n);
- CopyShadowAndOrigin(res, src, copy_size, &stack);
- __msan_unpoison(res + copy_size, 1); // \0
- return res;
-}
-
-#if !SANITIZER_FREEBSD
-INTERCEPTOR(char *, __strndup, char *src, SIZE_T n) {
- ENSURE_MSAN_INITED();
- GET_STORE_STACK_TRACE;
- SIZE_T copy_size = REAL(strnlen)(src, n);
- char *res = REAL(__strndup)(src, n);
- CopyShadowAndOrigin(res, src, copy_size, &stack);
- __msan_unpoison(res + copy_size, 1); // \0
- return res;
-}
-#define MSAN_MAYBE_INTERCEPT___STRNDUP INTERCEPT_FUNCTION(__strndup)
-#else
-#define MSAN_MAYBE_INTERCEPT___STRNDUP
-#endif
-
INTERCEPTOR(char *, gcvt, double number, SIZE_T ndigit, char *buf) {
ENSURE_MSAN_INITED();
char *res = REAL(gcvt)(number, ndigit, buf);
return __msan_memcpy(to, from, size); \
}
+#define COMMON_INTERCEPTOR_COPY_STRING(ctx, to, from, size) \
+ do { \
+ GET_STORE_STACK_TRACE; \
+ CopyShadowAndOrigin(to, from, size, &stack); \
+ __msan_unpoison(to + size, 1); \
+ } while (false)
+
#include "sanitizer_common/sanitizer_platform_interceptors.h"
#include "sanitizer_common/sanitizer_common_interceptors.inc"
INTERCEPT_FUNCTION(stpcpy); // NOLINT
INTERCEPT_FUNCTION(strdup);
MSAN_MAYBE_INTERCEPT___STRDUP;
- INTERCEPT_FUNCTION(strndup);
- MSAN_MAYBE_INTERCEPT___STRNDUP;
INTERCEPT_FUNCTION(strncpy); // NOLINT
INTERCEPT_FUNCTION(gcvt);
INTERCEPT_FUNCTION(strcat); // NOLINT
TEST(MemorySanitizer, strndup) {
char buf[4] = "abc";
__msan_poison(buf + 2, sizeof(*buf));
- char *x = strndup(buf, 3);
+ char *x;
+ EXPECT_UMR(x = strndup(buf, 3));
EXPECT_NOT_POISONED(x[0]);
EXPECT_NOT_POISONED(x[1]);
EXPECT_POISONED(x[2]);
char buf[4] = "abc";
__msan_poison(buf + 1, sizeof(*buf));
__msan_poison(buf + 2, sizeof(*buf));
- char *x = strndup(buf, 2);
+ char *x;
+ EXPECT_UMR(x = strndup(buf, 2));
EXPECT_NOT_POISONED(x[0]);
EXPECT_POISONED(x[1]);
EXPECT_NOT_POISONED(x[2]);
// COMMON_INTERCEPTOR_MEMSET_IMPL
// COMMON_INTERCEPTOR_MEMMOVE_IMPL
// COMMON_INTERCEPTOR_MEMCPY_IMPL
+// COMMON_INTERCEPTOR_COPY_STRING
+// COMMON_INTERCEPTOR_STRNDUP_IMPL
//===----------------------------------------------------------------------===//
#include "interception/interception.h"
}
#endif
+#ifndef COMMON_INTERCEPTOR_COPY_STRING
+#define COMMON_INTERCEPTOR_COPY_STRING(ctx, to, from, size) {}
+#endif
+
+#ifndef COMMON_INTERCEPTOR_STRNDUP_IMPL
+#define COMMON_INTERCEPTOR_STRNDUP_IMPL(ctx, s, size) \
+ COMMON_INTERCEPTOR_ENTER(ctx, strndup, s, size); \
+ uptr from_length = internal_strnlen(s, size); \
+ uptr copy_length = Min(size, from_length); \
+ char *new_mem = (char *)WRAP(malloc)(copy_length + 1); \
+ if (common_flags()->intercept_strndup) { \
+ COMMON_INTERCEPTOR_READ_RANGE(ctx, s, copy_length + 1); \
+ } \
+ COMMON_INTERCEPTOR_COPY_STRING(ctx, new_mem, s, copy_length); \
+ internal_memcpy(new_mem, s, copy_length); \
+ new_mem[copy_length] = '\0'; \
+ return new_mem;
+#endif
+
struct FileMetadata {
// For open_memstream().
char **addr;
#define INIT_STRNLEN
#endif
+#if SANITIZER_INTERCEPT_STRNDUP
+INTERCEPTOR(char*, strndup, const char *s, uptr size) {
+ void *ctx;
+ COMMON_INTERCEPTOR_STRNDUP_IMPL(ctx, s, size);
+}
+#define INIT_STRNDUP COMMON_INTERCEPT_FUNCTION(strndup)
+#else
+#define INIT_STRNDUP
+#endif // SANITIZER_INTERCEPT_STRNDUP
+
+#if SANITIZER_INTERCEPT___STRNDUP
+INTERCEPTOR(char*, __strndup, const char *s, uptr size) {
+ void *ctx;
+ COMMON_INTERCEPTOR_STRNDUP_IMPL(ctx, s, size);
+}
+#define INIT___STRNDUP COMMON_INTERCEPT_FUNCTION(__strndup)
+#else
+#define INIT___STRNDUP
+#endif // SANITIZER_INTERCEPT___STRNDUP
+
#if SANITIZER_INTERCEPT_TEXTDOMAIN
INTERCEPTOR(char*, textdomain, const char *domainname) {
void *ctx;
INIT_TEXTDOMAIN;
INIT_STRLEN;
INIT_STRNLEN;
+ INIT_STRNDUP;
+ INIT___STRNDUP;
INIT_STRCMP;
INIT_STRNCMP;
INIT_STRCASECMP;
COMMON_FLAG(bool, intercept_strlen, true,
"If set, uses custom wrappers for strlen and strnlen functions "
"to find more errors.")
+COMMON_FLAG(bool, intercept_strndup, true,
+ "If set, uses custom wrappers for strndup functions "
+ "to find more errors.")
COMMON_FLAG(bool, intercept_strchr, true,
"If set, uses custom wrappers for strchr, strchrnul, and strrchr "
"functions to find more errors.")
# define SI_NOT_WINDOWS 0
#endif
+#if SANITIZER_POSIX
+# define SI_POSIX 1
+#else
+# define SI_POSIX 0
+#endif
+
#if SANITIZER_LINUX && !SANITIZER_ANDROID
# define SI_LINUX_NOT_ANDROID 1
#else
# define SI_UNIX_NOT_MAC 0
#endif
+#if SANITIZER_LINUX && !SANITIZER_FREEBSD
+# define SI_LINUX_NOT_FREEBSD 1
+# else
+# define SI_LINUX_NOT_FREEBSD 0
+#endif
+
#define SANITIZER_INTERCEPT_STRLEN 1
#define SANITIZER_INTERCEPT_STRNLEN SI_NOT_MAC
#define SANITIZER_INTERCEPT_STRCMP 1
#define SANITIZER_INTERCEPT_MEMMOVE 1
#define SANITIZER_INTERCEPT_MEMCPY 1
#define SANITIZER_INTERCEPT_MEMCMP 1
+#define SANITIZER_INTERCEPT_STRNDUP SI_POSIX
+#define SANITIZER_INTERCEPT___STRNDUP SI_LINUX_NOT_FREEBSD
#if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) && \
__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 1070
# define SI_MAC_DEPLOYMENT_BELOW_10_7 1
# define SANITIZER_TEST_HAS_PRINTF_L 0
#endif
+#if !defined(_MSC_VER)
+# define SANITIZER_TEST_HAS_STRNDUP 1
+#else
+# define SANITIZER_TEST_HAS_STRNDUP 0
+#endif
+
#endif // SANITIZER_TEST_UTILS_H
--- /dev/null
+// 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
+
+// When built as C on Linux, strndup is transformed to __strndup.
+// RUN: %clangxx_asan -O3 -xc %s -o %t && not %run %t 2>&1 | FileCheck %s
+
+// UNSUPPORTED: win32
+
+#include <string.h>
+
+char kString[] = "foo";
+
+int main(int argc, char **argv) {
+ char *copy = strndup(kString, 2);
+ int x = copy[2 + argc]; // BOOM
+ // CHECK: AddressSanitizer: heap-buffer-overflow
+ // CHECK: #0 {{.*}}main {{.*}}strndup_oob_test.cc:[[@LINE-2]]
+ // CHECK-LABEL: allocated by thread T{{.*}} here:
+ // CHECK: #{{[01]}} {{.*}}strndup
+ // CHECK: #{{.*}}main {{.*}}strndup_oob_test.cc:[[@LINE-6]]
+ // CHECK-LABEL: SUMMARY
+ // CHECK: strndup_oob_test.cc:[[@LINE-7]]
+ return x;
+}
--- /dev/null
+// RUN: %clangxx_msan %s -o %t && not %run %t 2>&1 | FileCheck --check-prefix=ON %s
+// RUN: %clangxx_msan %s -o %t && MSAN_OPTIONS=intercept_strndup=0 %run %t 2>&1 | FileCheck --check-prefix=OFF --allow-empty %s
+
+// When built as C on Linux, strndup is transformed to __strndup.
+// RUN: %clangxx_msan -O3 -xc %s -o %t && not %run %t 2>&1 | FileCheck --check-prefix=ON %s
+
+// UNSUPPORTED: win32
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sanitizer/msan_interface.h>
+
+int main(int argc, char **argv) {
+ char kString[4] = "abc";
+ __msan_poison(kString + 2, 1);
+ char *copy = strndup(kString, 4); // BOOM
+ assert(__msan_test_shadow(copy, 4) == 2); // Poisoning is preserved.
+ free(copy);
+ return 0;
+ // ON: Uninitialized bytes in __interceptor_{{(__)?}}strndup at offset 2 inside [{{.*}}, 4)
+ // ON: MemorySanitizer: use-of-uninitialized-value
+ // ON: #0 {{.*}}main {{.*}}strndup.cc:[[@LINE-6]]
+ // ON-LABEL: SUMMARY
+ // ON: {{.*}}strndup.cc:[[@LINE-8]]
+ // OFF-NOT: MemorySanitizer
+}
+