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-rw-r--r--libsanitizer/asan/asan_mac.cc218
1 files changed, 34 insertions, 184 deletions
diff --git a/libsanitizer/asan/asan_mac.cc b/libsanitizer/asan/asan_mac.cc
index ab3c6560825b..4bf79be1728b 100644
--- a/libsanitizer/asan/asan_mac.cc
+++ b/libsanitizer/asan/asan_mac.cc
@@ -22,18 +22,11 @@
#include "sanitizer_common/sanitizer_libc.h"
#include "sanitizer_common/sanitizer_mac.h"
-#if !SANITIZER_IOS
-#include <crt_externs.h> // for _NSGetArgv and _NSGetEnviron
-#else
-extern "C" {
- extern char ***_NSGetArgv(void);
-}
-#endif
-
-#include <dlfcn.h> // for dladdr()
+#include <dlfcn.h>
#include <fcntl.h>
#include <libkern/OSAtomic.h>
#include <mach-o/dyld.h>
+#include <mach-o/getsect.h>
#include <mach-o/loader.h>
#include <pthread.h>
#include <stdlib.h> // for free()
@@ -43,193 +36,26 @@ extern "C" {
#include <sys/ucontext.h>
#include <unistd.h>
+// from <crt_externs.h>, but we don't have that file on iOS
+extern "C" {
+ extern char ***_NSGetArgv(void);
+ extern char ***_NSGetEnviron(void);
+}
+
namespace __asan {
void InitializePlatformInterceptors() {}
+void InitializePlatformExceptionHandlers() {}
bool PlatformHasDifferentMemcpyAndMemmove() {
// On OS X 10.7 memcpy() and memmove() are both resolved
// into memmove$VARIANT$sse42.
- // See also http://code.google.com/p/address-sanitizer/issues/detail?id=34.
+ // See also https://github.com/google/sanitizers/issues/34.
// TODO(glider): need to check dynamically that memcpy() and memmove() are
// actually the same function.
return GetMacosVersion() == MACOS_VERSION_SNOW_LEOPARD;
}
-extern "C"
-void __asan_init();
-
-static const char kDyldInsertLibraries[] = "DYLD_INSERT_LIBRARIES";
-LowLevelAllocator allocator_for_env;
-
-// Change the value of the env var |name|, leaking the original value.
-// If |name_value| is NULL, the variable is deleted from the environment,
-// otherwise the corresponding "NAME=value" string is replaced with
-// |name_value|.
-void LeakyResetEnv(const char *name, const char *name_value) {
- char **env = GetEnviron();
- uptr name_len = internal_strlen(name);
- while (*env != 0) {
- uptr len = internal_strlen(*env);
- if (len > name_len) {
- const char *p = *env;
- if (!internal_memcmp(p, name, name_len) && p[name_len] == '=') {
- // Match.
- if (name_value) {
- // Replace the old value with the new one.
- *env = const_cast<char*>(name_value);
- } else {
- // Shift the subsequent pointers back.
- char **del = env;
- do {
- del[0] = del[1];
- } while (*del++);
- }
- }
- }
- env++;
- }
-}
-
-static bool reexec_disabled = false;
-
-void DisableReexec() {
- reexec_disabled = true;
-}
-
-extern "C" SANITIZER_WEAK_ATTRIBUTE double dyldVersionNumber;
-static const double kMinDyldVersionWithAutoInterposition = 360.0;
-
-bool DyldNeedsEnvVariable() {
- // Although sanitizer support was added to LLVM on OS X 10.7+, GCC users
- // still may want use them on older systems. On older Darwin platforms, dyld
- // doesn't export dyldVersionNumber symbol and we simply return true.
- if (!&dyldVersionNumber) return true;
- // If running on OS X 10.11+ or iOS 9.0+, dyld will interpose even if
- // DYLD_INSERT_LIBRARIES is not set. However, checking OS version via
- // GetMacosVersion() doesn't work for the simulator. Let's instead check
- // `dyldVersionNumber`, which is exported by dyld, against a known version
- // number from the first OS release where this appeared.
- return dyldVersionNumber < kMinDyldVersionWithAutoInterposition;
-}
-
-void MaybeReexec() {
- if (reexec_disabled) return;
-
- // Make sure the dynamic ASan runtime library is preloaded so that the
- // wrappers work. If it is not, set DYLD_INSERT_LIBRARIES and re-exec
- // ourselves.
- Dl_info info;
- CHECK(dladdr((void*)((uptr)__asan_init), &info));
- char *dyld_insert_libraries =
- const_cast<char*>(GetEnv(kDyldInsertLibraries));
- uptr old_env_len = dyld_insert_libraries ?
- internal_strlen(dyld_insert_libraries) : 0;
- uptr fname_len = internal_strlen(info.dli_fname);
- const char *dylib_name = StripModuleName(info.dli_fname);
- uptr dylib_name_len = internal_strlen(dylib_name);
-
- bool lib_is_in_env =
- dyld_insert_libraries && REAL(strstr)(dyld_insert_libraries, dylib_name);
- if (DyldNeedsEnvVariable() && !lib_is_in_env) {
- // DYLD_INSERT_LIBRARIES is not set or does not contain the runtime
- // library.
- char program_name[1024];
- uint32_t buf_size = sizeof(program_name);
- _NSGetExecutablePath(program_name, &buf_size);
- char *new_env = const_cast<char*>(info.dli_fname);
- if (dyld_insert_libraries) {
- // Append the runtime dylib name to the existing value of
- // DYLD_INSERT_LIBRARIES.
- new_env = (char*)allocator_for_env.Allocate(old_env_len + fname_len + 2);
- internal_strncpy(new_env, dyld_insert_libraries, old_env_len);
- new_env[old_env_len] = ':';
- // Copy fname_len and add a trailing zero.
- internal_strncpy(new_env + old_env_len + 1, info.dli_fname,
- fname_len + 1);
- // Ok to use setenv() since the wrappers don't depend on the value of
- // asan_inited.
- setenv(kDyldInsertLibraries, new_env, /*overwrite*/1);
- } else {
- // Set DYLD_INSERT_LIBRARIES equal to the runtime dylib name.
- setenv(kDyldInsertLibraries, info.dli_fname, /*overwrite*/0);
- }
- VReport(1, "exec()-ing the program with\n");
- VReport(1, "%s=%s\n", kDyldInsertLibraries, new_env);
- VReport(1, "to enable ASan wrappers.\n");
- execv(program_name, *_NSGetArgv());
-
- // We get here only if execv() failed.
- Report("ERROR: The process is launched without DYLD_INSERT_LIBRARIES, "
- "which is required for ASan to work. ASan tried to set the "
- "environment variable and re-execute itself, but execv() failed, "
- "possibly because of sandbox restrictions. Make sure to launch the "
- "executable with:\n%s=%s\n", kDyldInsertLibraries, new_env);
- CHECK("execv failed" && 0);
- }
-
- if (!lib_is_in_env)
- return;
-
- // DYLD_INSERT_LIBRARIES is set and contains the runtime library. Let's remove
- // the dylib from the environment variable, because interceptors are installed
- // and we don't want our children to inherit the variable.
-
- uptr env_name_len = internal_strlen(kDyldInsertLibraries);
- // Allocate memory to hold the previous env var name, its value, the '='
- // sign and the '\0' char.
- char *new_env = (char*)allocator_for_env.Allocate(
- old_env_len + 2 + env_name_len);
- CHECK(new_env);
- internal_memset(new_env, '\0', old_env_len + 2 + env_name_len);
- internal_strncpy(new_env, kDyldInsertLibraries, env_name_len);
- new_env[env_name_len] = '=';
- char *new_env_pos = new_env + env_name_len + 1;
-
- // Iterate over colon-separated pieces of |dyld_insert_libraries|.
- char *piece_start = dyld_insert_libraries;
- char *piece_end = NULL;
- char *old_env_end = dyld_insert_libraries + old_env_len;
- do {
- if (piece_start[0] == ':') piece_start++;
- piece_end = REAL(strchr)(piece_start, ':');
- if (!piece_end) piece_end = dyld_insert_libraries + old_env_len;
- if ((uptr)(piece_start - dyld_insert_libraries) > old_env_len) break;
- uptr piece_len = piece_end - piece_start;
-
- char *filename_start =
- (char *)internal_memrchr(piece_start, '/', piece_len);
- uptr filename_len = piece_len;
- if (filename_start) {
- filename_start += 1;
- filename_len = piece_len - (filename_start - piece_start);
- } else {
- filename_start = piece_start;
- }
-
- // If the current piece isn't the runtime library name,
- // append it to new_env.
- if ((dylib_name_len != filename_len) ||
- (internal_memcmp(filename_start, dylib_name, dylib_name_len) != 0)) {
- if (new_env_pos != new_env + env_name_len + 1) {
- new_env_pos[0] = ':';
- new_env_pos++;
- }
- internal_strncpy(new_env_pos, piece_start, piece_len);
- new_env_pos += piece_len;
- }
- // Move on to the next piece.
- piece_start = piece_end;
- } while (piece_start < old_env_end);
-
- // Can't use setenv() here, because it requires the allocator to be
- // initialized.
- // FIXME: instead of filtering DYLD_INSERT_LIBRARIES here, do it in
- // a separate function called after InitializeAllocator().
- if (new_env_pos == new_env + env_name_len + 1) new_env = NULL;
- LeakyResetEnv(kDyldInsertLibraries, new_env);
-}
-
// No-op. Mac does not support static linkage anyway.
void *AsanDoesNotSupportStaticLinkage() {
return 0;
@@ -241,6 +67,30 @@ void AsanCheckDynamicRTPrereqs() {}
// No-op. Mac does not support static linkage anyway.
void AsanCheckIncompatibleRT() {}
+void AsanApplyToGlobals(globals_op_fptr op, const void *needle) {
+ // Find the Mach-O header for the image containing the needle
+ Dl_info info;
+ int err = dladdr(needle, &info);
+ if (err == 0) return;
+
+#if __LP64__
+ const struct mach_header_64 *mh = (struct mach_header_64 *)info.dli_fbase;
+#else
+ const struct mach_header *mh = (struct mach_header *)info.dli_fbase;
+#endif
+
+ // Look up the __asan_globals section in that image and register its globals
+ unsigned long size = 0;
+ __asan_global *globals = (__asan_global *)getsectiondata(
+ mh,
+ "__DATA", "__asan_globals",
+ &size);
+
+ if (!globals) return;
+ if (size % sizeof(__asan_global) != 0) return;
+ op(globals, size / sizeof(__asan_global));
+}
+
void ReadContextStack(void *context, uptr *stack, uptr *ssize) {
UNIMPLEMENTED();
}