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-rw-r--r--lib/asan/asan_malloc_linux.cpp307
1 files changed, 307 insertions, 0 deletions
diff --git a/lib/asan/asan_malloc_linux.cpp b/lib/asan/asan_malloc_linux.cpp
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+++ b/lib/asan/asan_malloc_linux.cpp
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+//===-- asan_malloc_linux.cpp ---------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of AddressSanitizer, an address sanity checker.
+//
+// Linux-specific malloc interception.
+// We simply define functions like malloc, free, realloc, etc.
+// They will replace the corresponding libc functions automagically.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_platform.h"
+#if SANITIZER_FREEBSD || SANITIZER_FUCHSIA || SANITIZER_LINUX || \
+ SANITIZER_NETBSD || SANITIZER_RTEMS || SANITIZER_SOLARIS
+
+#include "sanitizer_common/sanitizer_allocator_checks.h"
+#include "sanitizer_common/sanitizer_errno.h"
+#include "sanitizer_common/sanitizer_tls_get_addr.h"
+#include "asan_allocator.h"
+#include "asan_interceptors.h"
+#include "asan_internal.h"
+#include "asan_malloc_local.h"
+#include "asan_stack.h"
+
+// ---------------------- Replacement functions ---------------- {{{1
+using namespace __asan;
+
+static uptr allocated_for_dlsym;
+static uptr last_dlsym_alloc_size_in_words;
+static const uptr kDlsymAllocPoolSize = SANITIZER_RTEMS ? 4096 : 1024;
+static uptr alloc_memory_for_dlsym[kDlsymAllocPoolSize];
+
+static INLINE bool IsInDlsymAllocPool(const void *ptr) {
+ uptr off = (uptr)ptr - (uptr)alloc_memory_for_dlsym;
+ return off < allocated_for_dlsym * sizeof(alloc_memory_for_dlsym[0]);
+}
+
+static void *AllocateFromLocalPool(uptr size_in_bytes) {
+ uptr size_in_words = RoundUpTo(size_in_bytes, kWordSize) / kWordSize;
+ void *mem = (void*)&alloc_memory_for_dlsym[allocated_for_dlsym];
+ last_dlsym_alloc_size_in_words = size_in_words;
+ allocated_for_dlsym += size_in_words;
+ CHECK_LT(allocated_for_dlsym, kDlsymAllocPoolSize);
+ return mem;
+}
+
+static void DeallocateFromLocalPool(const void *ptr) {
+ // Hack: since glibc 2.27 dlsym no longer uses stack-allocated memory to store
+ // error messages and instead uses malloc followed by free. To avoid pool
+ // exhaustion due to long object filenames, handle that special case here.
+ uptr prev_offset = allocated_for_dlsym - last_dlsym_alloc_size_in_words;
+ void *prev_mem = (void*)&alloc_memory_for_dlsym[prev_offset];
+ if (prev_mem == ptr) {
+ REAL(memset)(prev_mem, 0, last_dlsym_alloc_size_in_words * kWordSize);
+ allocated_for_dlsym = prev_offset;
+ last_dlsym_alloc_size_in_words = 0;
+ }
+}
+
+static int PosixMemalignFromLocalPool(void **memptr, uptr alignment,
+ uptr size_in_bytes) {
+ if (UNLIKELY(!CheckPosixMemalignAlignment(alignment)))
+ return errno_EINVAL;
+
+ CHECK(alignment >= kWordSize);
+
+ uptr addr = (uptr)&alloc_memory_for_dlsym[allocated_for_dlsym];
+ uptr aligned_addr = RoundUpTo(addr, alignment);
+ uptr aligned_size = RoundUpTo(size_in_bytes, kWordSize);
+
+ uptr *end_mem = (uptr*)(aligned_addr + aligned_size);
+ uptr allocated = end_mem - alloc_memory_for_dlsym;
+ if (allocated >= kDlsymAllocPoolSize)
+ return errno_ENOMEM;
+
+ allocated_for_dlsym = allocated;
+ *memptr = (void*)aligned_addr;
+ return 0;
+}
+
+#if SANITIZER_RTEMS
+void* MemalignFromLocalPool(uptr alignment, uptr size) {
+ void *ptr = nullptr;
+ alignment = Max(alignment, kWordSize);
+ PosixMemalignFromLocalPool(&ptr, alignment, size);
+ return ptr;
+}
+
+bool IsFromLocalPool(const void *ptr) {
+ return IsInDlsymAllocPool(ptr);
+}
+#endif
+
+static INLINE bool MaybeInDlsym() {
+ // Fuchsia doesn't use dlsym-based interceptors.
+ return !SANITIZER_FUCHSIA && asan_init_is_running;
+}
+
+static INLINE bool UseLocalPool() {
+ return EarlyMalloc() || MaybeInDlsym();
+}
+
+static void *ReallocFromLocalPool(void *ptr, uptr size) {
+ const uptr offset = (uptr)ptr - (uptr)alloc_memory_for_dlsym;
+ const uptr copy_size = Min(size, kDlsymAllocPoolSize - offset);
+ void *new_ptr;
+ if (UNLIKELY(UseLocalPool())) {
+ new_ptr = AllocateFromLocalPool(size);
+ } else {
+ ENSURE_ASAN_INITED();
+ GET_STACK_TRACE_MALLOC;
+ new_ptr = asan_malloc(size, &stack);
+ }
+ internal_memcpy(new_ptr, ptr, copy_size);
+ return new_ptr;
+}
+
+INTERCEPTOR(void, free, void *ptr) {
+ GET_STACK_TRACE_FREE;
+ if (UNLIKELY(IsInDlsymAllocPool(ptr))) {
+ DeallocateFromLocalPool(ptr);
+ return;
+ }
+ asan_free(ptr, &stack, FROM_MALLOC);
+}
+
+#if SANITIZER_INTERCEPT_CFREE
+INTERCEPTOR(void, cfree, void *ptr) {
+ GET_STACK_TRACE_FREE;
+ if (UNLIKELY(IsInDlsymAllocPool(ptr)))
+ return;
+ asan_free(ptr, &stack, FROM_MALLOC);
+}
+#endif // SANITIZER_INTERCEPT_CFREE
+
+INTERCEPTOR(void*, malloc, uptr size) {
+ if (UNLIKELY(UseLocalPool()))
+ // Hack: dlsym calls malloc before REAL(malloc) is retrieved from dlsym.
+ return AllocateFromLocalPool(size);
+ ENSURE_ASAN_INITED();
+ GET_STACK_TRACE_MALLOC;
+ return asan_malloc(size, &stack);
+}
+
+INTERCEPTOR(void*, calloc, uptr nmemb, uptr size) {
+ if (UNLIKELY(UseLocalPool()))
+ // Hack: dlsym calls calloc before REAL(calloc) is retrieved from dlsym.
+ return AllocateFromLocalPool(nmemb * size);
+ ENSURE_ASAN_INITED();
+ GET_STACK_TRACE_MALLOC;
+ return asan_calloc(nmemb, size, &stack);
+}
+
+INTERCEPTOR(void*, realloc, void *ptr, uptr size) {
+ if (UNLIKELY(IsInDlsymAllocPool(ptr)))
+ return ReallocFromLocalPool(ptr, size);
+ if (UNLIKELY(UseLocalPool()))
+ return AllocateFromLocalPool(size);
+ ENSURE_ASAN_INITED();
+ GET_STACK_TRACE_MALLOC;
+ return asan_realloc(ptr, size, &stack);
+}
+
+#if SANITIZER_INTERCEPT_REALLOCARRAY
+INTERCEPTOR(void*, reallocarray, void *ptr, uptr nmemb, uptr size) {
+ ENSURE_ASAN_INITED();
+ GET_STACK_TRACE_MALLOC;
+ return asan_reallocarray(ptr, nmemb, size, &stack);
+}
+#endif // SANITIZER_INTERCEPT_REALLOCARRAY
+
+#if SANITIZER_INTERCEPT_MEMALIGN
+INTERCEPTOR(void*, memalign, uptr boundary, uptr size) {
+ GET_STACK_TRACE_MALLOC;
+ return asan_memalign(boundary, size, &stack, FROM_MALLOC);
+}
+
+INTERCEPTOR(void*, __libc_memalign, uptr boundary, uptr size) {
+ GET_STACK_TRACE_MALLOC;
+ void *res = asan_memalign(boundary, size, &stack, FROM_MALLOC);
+ DTLS_on_libc_memalign(res, size);
+ return res;
+}
+#endif // SANITIZER_INTERCEPT_MEMALIGN
+
+#if SANITIZER_INTERCEPT_ALIGNED_ALLOC
+INTERCEPTOR(void*, aligned_alloc, uptr boundary, uptr size) {
+ GET_STACK_TRACE_MALLOC;
+ return asan_aligned_alloc(boundary, size, &stack);
+}
+#endif // SANITIZER_INTERCEPT_ALIGNED_ALLOC
+
+INTERCEPTOR(uptr, malloc_usable_size, void *ptr) {
+ GET_CURRENT_PC_BP_SP;
+ (void)sp;
+ return asan_malloc_usable_size(ptr, pc, bp);
+}
+
+#if SANITIZER_INTERCEPT_MALLOPT_AND_MALLINFO
+// We avoid including malloc.h for portability reasons.
+// man mallinfo says the fields are "long", but the implementation uses int.
+// It doesn't matter much -- we just need to make sure that the libc's mallinfo
+// is not called.
+struct fake_mallinfo {
+ int x[10];
+};
+
+INTERCEPTOR(struct fake_mallinfo, mallinfo, void) {
+ struct fake_mallinfo res;
+ REAL(memset)(&res, 0, sizeof(res));
+ return res;
+}
+
+INTERCEPTOR(int, mallopt, int cmd, int value) {
+ return 0;
+}
+#endif // SANITIZER_INTERCEPT_MALLOPT_AND_MALLINFO
+
+INTERCEPTOR(int, posix_memalign, void **memptr, uptr alignment, uptr size) {
+ if (UNLIKELY(UseLocalPool()))
+ return PosixMemalignFromLocalPool(memptr, alignment, size);
+ GET_STACK_TRACE_MALLOC;
+ return asan_posix_memalign(memptr, alignment, size, &stack);
+}
+
+INTERCEPTOR(void*, valloc, uptr size) {
+ GET_STACK_TRACE_MALLOC;
+ return asan_valloc(size, &stack);
+}
+
+#if SANITIZER_INTERCEPT_PVALLOC
+INTERCEPTOR(void*, pvalloc, uptr size) {
+ GET_STACK_TRACE_MALLOC;
+ return asan_pvalloc(size, &stack);
+}
+#endif // SANITIZER_INTERCEPT_PVALLOC
+
+INTERCEPTOR(void, malloc_stats, void) {
+ __asan_print_accumulated_stats();
+}
+
+#if SANITIZER_ANDROID
+// Format of __libc_malloc_dispatch has changed in Android L.
+// While we are moving towards a solution that does not depend on bionic
+// internals, here is something to support both K* and L releases.
+struct MallocDebugK {
+ void *(*malloc)(uptr bytes);
+ void (*free)(void *mem);
+ void *(*calloc)(uptr n_elements, uptr elem_size);
+ void *(*realloc)(void *oldMem, uptr bytes);
+ void *(*memalign)(uptr alignment, uptr bytes);
+ uptr (*malloc_usable_size)(void *mem);
+};
+
+struct MallocDebugL {
+ void *(*calloc)(uptr n_elements, uptr elem_size);
+ void (*free)(void *mem);
+ fake_mallinfo (*mallinfo)(void);
+ void *(*malloc)(uptr bytes);
+ uptr (*malloc_usable_size)(void *mem);
+ void *(*memalign)(uptr alignment, uptr bytes);
+ int (*posix_memalign)(void **memptr, uptr alignment, uptr size);
+ void* (*pvalloc)(uptr size);
+ void *(*realloc)(void *oldMem, uptr bytes);
+ void* (*valloc)(uptr size);
+};
+
+ALIGNED(32) const MallocDebugK asan_malloc_dispatch_k = {
+ WRAP(malloc), WRAP(free), WRAP(calloc),
+ WRAP(realloc), WRAP(memalign), WRAP(malloc_usable_size)};
+
+ALIGNED(32) const MallocDebugL asan_malloc_dispatch_l = {
+ WRAP(calloc), WRAP(free), WRAP(mallinfo),
+ WRAP(malloc), WRAP(malloc_usable_size), WRAP(memalign),
+ WRAP(posix_memalign), WRAP(pvalloc), WRAP(realloc),
+ WRAP(valloc)};
+
+namespace __asan {
+void ReplaceSystemMalloc() {
+ void **__libc_malloc_dispatch_p =
+ (void **)AsanDlSymNext("__libc_malloc_dispatch");
+ if (__libc_malloc_dispatch_p) {
+ // Decide on K vs L dispatch format by the presence of
+ // __libc_malloc_default_dispatch export in libc.
+ void *default_dispatch_p = AsanDlSymNext("__libc_malloc_default_dispatch");
+ if (default_dispatch_p)
+ *__libc_malloc_dispatch_p = (void *)&asan_malloc_dispatch_k;
+ else
+ *__libc_malloc_dispatch_p = (void *)&asan_malloc_dispatch_l;
+ }
+}
+} // namespace __asan
+
+#else // SANITIZER_ANDROID
+
+namespace __asan {
+void ReplaceSystemMalloc() {
+}
+} // namespace __asan
+#endif // SANITIZER_ANDROID
+
+#endif // SANITIZER_FREEBSD || SANITIZER_FUCHSIA || SANITIZER_LINUX ||
+ // SANITIZER_NETBSD || SANITIZER_SOLARIS