//===-- esan_interceptors.cpp ---------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of EfficiencySanitizer, a family of performance tuners.
//
// Interception routines for the esan run-time.
//===----------------------------------------------------------------------===//
#include "esan.h"
#include "esan_shadow.h"
#include "interception/interception.h"
#include "sanitizer_common/sanitizer_common.h"
#include "sanitizer_common/sanitizer_libc.h"
#include "sanitizer_common/sanitizer_linux.h"
#include "sanitizer_common/sanitizer_stacktrace.h"
using namespace __esan; // NOLINT
#define CUR_PC() (StackTrace::GetCurrentPc())
//===----------------------------------------------------------------------===//
// Interception via sanitizer common interceptors
//===----------------------------------------------------------------------===//
// Get the per-platform defines for what is possible to intercept
#include "sanitizer_common/sanitizer_platform_interceptors.h"
// TODO(bruening): tsan disables several interceptors (getpwent, etc.) claiming
// that interception is a perf hit: should we do the same?
// We have no need to intercept:
#undef SANITIZER_INTERCEPT_TLS_GET_ADDR
// TODO(bruening): the common realpath interceptor assumes malloc is
// intercepted! We should try to parametrize that, though we'll
// intercept malloc soon ourselves and can then remove this undef.
#undef SANITIZER_INTERCEPT_REALPATH
// We provide our own version:
#undef SANITIZER_INTERCEPT_SIGPROCMASK
#define COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED (!EsanIsInitialized)
#define COMMON_INTERCEPT_FUNCTION(name) INTERCEPT_FUNCTION(name)
#define COMMON_INTERCEPT_FUNCTION_VER(name, ver) \
INTERCEPT_FUNCTION_VER(name, ver)
// We must initialize during early interceptors, to support tcmalloc.
// This means that for some apps we fully initialize prior to
// __esan_init() being called.
// We currently do not use ctx.
#define COMMON_INTERCEPTOR_ENTER(ctx, func, ...) \
do { \
if (UNLIKELY(COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED)) { \
if (!UNLIKELY(EsanDuringInit)) \
initializeLibrary(__esan_which_tool); \
return REAL(func)(__VA_ARGS__); \
} \
ctx = nullptr; \
(void)ctx; \
} while (false)
#define COMMON_INTERCEPTOR_ENTER_NOIGNORE(ctx, func, ...) \
COMMON_INTERCEPTOR_ENTER(ctx, func, __VA_ARGS__)
#define COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ptr, size) \
processRangeAccess(CUR_PC(), (uptr)ptr, size, true)
#define COMMON_INTERCEPTOR_READ_RANGE(ctx, ptr, size) \
processRangeAccess(CUR_PC(), (uptr)ptr, size, false)
// This is only called if the app explicitly calls exit(), not on
// a normal exit.
#define COMMON_INTERCEPTOR_ON_EXIT(ctx) finalizeLibrary()
#define COMMON_INTERCEPTOR_FILE_OPEN(ctx, file, path) \
do { \
(void)(ctx); \
(void)(file); \
(void)(path); \
} while (false)
#define COMMON_INTERCEPTOR_FILE_CLOSE(ctx, file) \
do { \
(void)(ctx); \
(void)(file); \
} while (false)
#define COMMON_INTERCEPTOR_LIBRARY_LOADED(filename, handle) \
do { \
(void)(filename); \
(void)(handle); \
} while (false)
#define COMMON_INTERCEPTOR_LIBRARY_UNLOADED() \
do { \
} while (false)
#define COMMON_INTERCEPTOR_ACQUIRE(ctx, u) \
do { \
(void)(ctx); \
(void)(u); \
} while (false)
#define COMMON_INTERCEPTOR_RELEASE(ctx, u) \
do { \
(void)(ctx); \
(void)(u); \
} while (false)
#define COMMON_INTERCEPTOR_DIR_ACQUIRE(ctx, path) \
do { \
(void)(ctx); \
(void)(path); \
} while (false)
#define COMMON_INTERCEPTOR_FD_ACQUIRE(ctx, fd) \
do { \
(void)(ctx); \
(void)(fd); \
} while (false)
#define COMMON_INTERCEPTOR_FD_RELEASE(ctx, fd) \
do { \
(void)(ctx); \
(void)(fd); \
} while (false)
#define COMMON_INTERCEPTOR_FD_ACCESS(ctx, fd) \
do { \
(void)(ctx); \
(void)(fd); \
} while (false)
#define COMMON_INTERCEPTOR_FD_SOCKET_ACCEPT(ctx, fd, newfd) \
do { \
(void)(ctx); \
(void)(fd); \
(void)(newfd); \
} while (false)
#define COMMON_INTERCEPTOR_SET_THREAD_NAME(ctx, name) \
do { \
(void)(ctx); \
(void)(name); \
} while (false)
#define COMMON_INTERCEPTOR_SET_PTHREAD_NAME(ctx, thread, name) \
do { \
(void)(ctx); \
(void)(thread); \
(void)(name); \
} while (false)
#define COMMON_INTERCEPTOR_BLOCK_REAL(name) REAL(name)
#define COMMON_INTERCEPTOR_MUTEX_LOCK(ctx, m) \
do { \
(void)(ctx); \
(void)(m); \
} while (false)
#define COMMON_INTERCEPTOR_MUTEX_UNLOCK(ctx, m) \
do { \
(void)(ctx); \
(void)(m); \
} while (false)
#define COMMON_INTERCEPTOR_MUTEX_REPAIR(ctx, m) \
do { \
(void)(ctx); \
(void)(m); \
} while (false)
#define COMMON_INTERCEPTOR_HANDLE_RECVMSG(ctx, msg) \
do { \
(void)(ctx); \
(void)(msg); \
} while (false)
#define COMMON_INTERCEPTOR_USER_CALLBACK_START() \
do { \
} while (false)
#define COMMON_INTERCEPTOR_USER_CALLBACK_END() \
do { \
} while (false)
#include "sanitizer_common/sanitizer_common_interceptors.inc"
//===----------------------------------------------------------------------===//
// Syscall interception
//===----------------------------------------------------------------------===//
// We want the caller's PC b/c unlike the other function interceptors these
// are separate pre and post functions called around the app's syscall().
#define COMMON_SYSCALL_PRE_READ_RANGE(ptr, size) \
processRangeAccess(GET_CALLER_PC(), (uptr)ptr, size, false)
#define COMMON_SYSCALL_PRE_WRITE_RANGE(ptr, size) \
do { \
(void)(ptr); \
(void)(size); \
} while (false)
#define COMMON_SYSCALL_POST_READ_RANGE(ptr, size) \
do { \
(void)(ptr); \
(void)(size); \
} while (false)
// The actual amount written is in post, not pre.
#define COMMON_SYSCALL_POST_WRITE_RANGE(ptr, size) \
processRangeAccess(GET_CALLER_PC(), (uptr)ptr, size, true)
#define COMMON_SYSCALL_ACQUIRE(addr) \
do { \
(void)(addr); \
} while (false)
#define COMMON_SYSCALL_RELEASE(addr) \
do { \
(void)(addr); \
} while (false)
#define COMMON_SYSCALL_FD_CLOSE(fd) \
do { \
(void)(fd); \
} while (false)
#define COMMON_SYSCALL_FD_ACQUIRE(fd) \
do { \
(void)(fd); \
} while (false)
#define COMMON_SYSCALL_FD_RELEASE(fd) \
do { \
(void)(fd); \
} while (false)
#define COMMON_SYSCALL_PRE_FORK() \
do { \
} while (false)
#define COMMON_SYSCALL_POST_FORK(res) \
do { \
(void)(res); \
} while (false)
#include "sanitizer_common/sanitizer_common_syscalls.inc"
//===----------------------------------------------------------------------===//
// Custom interceptors
//===----------------------------------------------------------------------===//
// TODO(bruening): move more of these to the common interception pool as they
// are shared with tsan and asan.
// While our other files match LLVM style, here we match sanitizer style as we
// expect to move these to the common pool.
INTERCEPTOR(char *, strcpy, char *dst, const char *src) { // NOLINT
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, strcpy, dst, src);
uptr srclen = internal_strlen(src);
COMMON_INTERCEPTOR_WRITE_RANGE(ctx, dst, srclen + 1);
COMMON_INTERCEPTOR_READ_RANGE(ctx, src, srclen + 1);
return REAL(strcpy)(dst, src); // NOLINT
}
INTERCEPTOR(char *, strncpy, char *dst, char *src, uptr n) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, strncpy, dst, src, n);
uptr srclen = internal_strnlen(src, n);
uptr copied_size = srclen + 1 > n ? n : srclen + 1;
COMMON_INTERCEPTOR_WRITE_RANGE(ctx, dst, copied_size);
COMMON_INTERCEPTOR_READ_RANGE(ctx, src, copied_size);
return REAL(strncpy)(dst, src, n);
}
INTERCEPTOR(int, open, const char *name, int flags, int mode) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, open, name, flags, mode);
COMMON_INTERCEPTOR_READ_STRING(ctx, name, 0);
return REAL(open)(name, flags, mode);
}
#if SANITIZER_LINUX
INTERCEPTOR(int, open64, const char *name, int flags, int mode) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, open64, name, flags, mode);
COMMON_INTERCEPTOR_READ_STRING(ctx, name, 0);
return REAL(open64)(name, flags, mode);
}
#define ESAN_MAYBE_INTERCEPT_OPEN64 INTERCEPT_FUNCTION(open64)
#else
#define ESAN_MAYBE_INTERCEPT_OPEN64
#endif
INTERCEPTOR(int, creat, const char *name, int mode) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, creat, name, mode);
COMMON_INTERCEPTOR_READ_STRING(ctx, name, 0);
return REAL(creat)(name, mode);
}
#if SANITIZER_LINUX
INTERCEPTOR(int, creat64, const char *name, int mode) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, creat64, name, mode);
COMMON_INTERCEPTOR_READ_STRING(ctx, name, 0);
return REAL(creat64)(name, mode);
}
#define ESAN_MAYBE_INTERCEPT_CREAT64 INTERCEPT_FUNCTION(creat64)
#else
#define ESAN_MAYBE_INTERCEPT_CREAT64
#endif
INTERCEPTOR(int, unlink, char *path) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, unlink, path);
COMMON_INTERCEPTOR_READ_STRING(ctx, path, 0);
return REAL(unlink)(path);
}
INTERCEPTOR(uptr, fread, void *ptr, uptr size, uptr nmemb, void *f) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, fread, ptr, size, nmemb, f);
COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ptr, size * nmemb);
return REAL(fread)(ptr, size, nmemb, f);
}
INTERCEPTOR(uptr, fwrite, const void *p, uptr size, uptr nmemb, void *f) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, fwrite, p, size, nmemb, f);
COMMON_INTERCEPTOR_READ_RANGE(ctx, p, size * nmemb);
return REAL(fwrite)(p, size, nmemb, f);
}
INTERCEPTOR(int, puts, const char *s) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, puts, s);
COMMON_INTERCEPTOR_READ_RANGE(ctx, s, internal_strlen(s));
return REAL(puts)(s);
}
INTERCEPTOR(int, rmdir, char *path) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, rmdir, path);
COMMON_INTERCEPTOR_READ_STRING(ctx, path, 0);
return REAL(rmdir)(path);
}
//===----------------------------------------------------------------------===//
// Shadow-related interceptors
//===----------------------------------------------------------------------===//
// These are candidates for sharing with all sanitizers if shadow memory
// support is also standardized.
INTERCEPTOR(void *, mmap, void *addr, SIZE_T sz, int prot, int flags,
int fd, OFF_T off) {
if (UNLIKELY(REAL(mmap) == nullptr)) {
// With esan init during interceptor init and a static libc preventing
// our early-calloc from triggering, we can end up here before our
// REAL pointer is set up.
return (void *)internal_mmap(addr, sz, prot, flags, fd, off);
}
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, mmap, addr, sz, prot, flags, fd, off);
if (!fixMmapAddr(&addr, sz, flags))
return (void *)-1;
void *result = REAL(mmap)(addr, sz, prot, flags, fd, off);
return (void *)checkMmapResult((uptr)result, sz);
}
#if SANITIZER_LINUX
INTERCEPTOR(void *, mmap64, void *addr, SIZE_T sz, int prot, int flags,
int fd, OFF64_T off) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, mmap64, addr, sz, prot, flags, fd, off);
if (!fixMmapAddr(&addr, sz, flags))
return (void *)-1;
void *result = REAL(mmap64)(addr, sz, prot, flags, fd, off);
return (void *)checkMmapResult((uptr)result, sz);
}
#define ESAN_MAYBE_INTERCEPT_MMAP64 INTERCEPT_FUNCTION(mmap64)
#else
#define ESAN_MAYBE_INTERCEPT_MMAP64
#endif
//===----------------------------------------------------------------------===//
// Signal-related interceptors
//===----------------------------------------------------------------------===//
#if SANITIZER_LINUX
typedef void (*signal_handler_t)(int);
INTERCEPTOR(signal_handler_t, signal, int signum, signal_handler_t handler) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, signal, signum, handler);
signal_handler_t result;
if (!processSignal(signum, handler, &result))
return result;
else
return REAL(signal)(signum, handler);
}
#define ESAN_MAYBE_INTERCEPT_SIGNAL INTERCEPT_FUNCTION(signal)
#else
#error Platform not supported
#define ESAN_MAYBE_INTERCEPT_SIGNAL
#endif
#if SANITIZER_LINUX
DECLARE_REAL(int, sigaction, int signum, const struct sigaction *act,
struct sigaction *oldact)
INTERCEPTOR(int, sigaction, int signum, const struct sigaction *act,
struct sigaction *oldact) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, sigaction, signum, act, oldact);
if (!processSigaction(signum, act, oldact))
return 0;
else
return REAL(sigaction)(signum, act, oldact);
}
// This is required to properly use internal_sigaction.
namespace __sanitizer {
int real_sigaction(int signum, const void *act, void *oldact) {
if (REAL(sigaction) == nullptr) {
// With an instrumented allocator, this is called during interceptor init
// and we need a raw syscall solution.
return internal_sigaction_syscall(signum, act, oldact);
}
return REAL(sigaction)(signum, (const struct sigaction *)act,
(struct sigaction *)oldact);
}
} // namespace __sanitizer
#define ESAN_MAYBE_INTERCEPT_SIGACTION INTERCEPT_FUNCTION(sigaction)
#else
#error Platform not supported
#define ESAN_MAYBE_INTERCEPT_SIGACTION
#endif
#if SANITIZER_LINUX
INTERCEPTOR(int, sigprocmask, int how, __sanitizer_sigset_t *set,
__sanitizer_sigset_t *oldset) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, sigprocmask, how, set, oldset);
int res = 0;
if (processSigprocmask(how, set, oldset))
res = REAL(sigprocmask)(how, set, oldset);
if (!res && oldset)
COMMON_INTERCEPTOR_WRITE_RANGE(ctx, oldset, sizeof(*oldset));
return res;
}
#define ESAN_MAYBE_INTERCEPT_SIGPROCMASK INTERCEPT_FUNCTION(sigprocmask)
#else
#define ESAN_MAYBE_INTERCEPT_SIGPROCMASK
#endif
#if !SANITIZER_WINDOWS
INTERCEPTOR(int, pthread_sigmask, int how, __sanitizer_sigset_t *set,
__sanitizer_sigset_t *oldset) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, pthread_sigmask, how, set, oldset);
int res = 0;
if (processSigprocmask(how, set, oldset))
res = REAL(sigprocmask)(how, set, oldset);
if (!res && oldset)
COMMON_INTERCEPTOR_WRITE_RANGE(ctx, oldset, sizeof(*oldset));
return res;
}
#define ESAN_MAYBE_INTERCEPT_PTHREAD_SIGMASK INTERCEPT_FUNCTION(pthread_sigmask)
#else
#define ESAN_MAYBE_INTERCEPT_PTHREAD_SIGMASK
#endif
//===----------------------------------------------------------------------===//
// Malloc interceptors
//===----------------------------------------------------------------------===//
static char early_alloc_buf[128];
static bool used_early_alloc_buf;
static void *handleEarlyAlloc(uptr size) {
// If esan is initialized during an interceptor (which happens with some
// tcmalloc implementations that call pthread_mutex_lock), the call from
// dlsym to calloc will deadlock. There is only one such calloc (dlsym
// allocates a single pthread key), so we work around it by using a
// static buffer for the calloc request. The loader currently needs
// 32 bytes but we size at 128 to allow for future changes.
// This solution will also allow us to deliberately intercept malloc & family
// in the future (to perform tool actions on each allocation, without
// replacing the allocator), as it also solves the problem of intercepting
// calloc when it will itself be called before its REAL pointer is
// initialized.
CHECK(!used_early_alloc_buf && size < sizeof(early_alloc_buf));
// We do not handle multiple threads here. This only happens at process init
// time, and while it's possible for a shared library to create early threads
// that race here, we consider that to be a corner case extreme enough that
// it's not worth the effort to handle.
used_early_alloc_buf = true;
return (void *)early_alloc_buf;
}
INTERCEPTOR(void*, calloc, uptr size, uptr n) {
if (EsanDuringInit && REAL(calloc) == nullptr)
return handleEarlyAlloc(size * n);
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, calloc, size, n);
void *res = REAL(calloc)(size, n);
// The memory is zeroed and thus is all written.
COMMON_INTERCEPTOR_WRITE_RANGE(nullptr, (uptr)res, size * n);
return res;
}
INTERCEPTOR(void, free, void *p) {
void *ctx;
COMMON_INTERCEPTOR_ENTER(ctx, free, p);
if (p == (void *)early_alloc_buf) {
// We expect just a singleton use but we clear this for cleanliness.
used_early_alloc_buf = false;
return;
}
REAL(free)(p);
}
namespace __esan {
void initializeInterceptors() {
InitializeCommonInterceptors();
INTERCEPT_FUNCTION(strcpy); // NOLINT
INTERCEPT_FUNCTION(strncpy);
INTERCEPT_FUNCTION(open);
ESAN_MAYBE_INTERCEPT_OPEN64;
INTERCEPT_FUNCTION(creat);
ESAN_MAYBE_INTERCEPT_CREAT64;
INTERCEPT_FUNCTION(unlink);
INTERCEPT_FUNCTION(fread);
INTERCEPT_FUNCTION(fwrite);
INTERCEPT_FUNCTION(puts);
INTERCEPT_FUNCTION(rmdir);
INTERCEPT_FUNCTION(mmap);
ESAN_MAYBE_INTERCEPT_MMAP64;
ESAN_MAYBE_INTERCEPT_SIGNAL;
ESAN_MAYBE_INTERCEPT_SIGACTION;
ESAN_MAYBE_INTERCEPT_SIGPROCMASK;
ESAN_MAYBE_INTERCEPT_PTHREAD_SIGMASK;
INTERCEPT_FUNCTION(calloc);
INTERCEPT_FUNCTION(free);
// TODO(bruening): intercept routines that other sanitizers intercept that
// are not in the common pool or here yet, ideally by adding to the common
// pool. Examples include wcslen and bcopy.
// TODO(bruening): there are many more libc routines that read or write data
// structures that no sanitizer is intercepting: sigaction, strtol, etc.
}
} // namespace __esan