Implement malloc_usable_size for debug impls.
- Implemented chk_memalign.
- Fixed a few bugs in leak_memalign.
- Implemented {leak,fill,check,qemu}_malloc_usable_size.
- Make malloc_usable_size update at run time.
- Add malloc_test.cpp as a small set of tests for the
malloc debug routines.
- Fix the qemu routines since it's been broken since it moved to C++.
- Add support for the %u format to the out_vformat in libc_logging.cpp.
This is used by the emulator code.
Tested using the bionic-unit-tests with setprop libc.debug.malloc
set to 1, 5, and 10.
I tested as much as possible on the emulator, but tracing doesn't appear
to be working properly.
Bug: 6143477
Merge change from internal master.
(cherry-picked from commit 3d594c258045783fc9e1956ce7a4d91e302f011e)
Change-Id: I4ae00fffba82315a8c283f35893fd554460722fb
diff --git a/libc/bionic/libc_logging.cpp b/libc/bionic/libc_logging.cpp
index 8de1192..74e599c 100644
--- a/libc/bionic/libc_logging.cpp
+++ b/libc/bionic/libc_logging.cpp
@@ -348,7 +348,7 @@
buffer[0] = '0';
buffer[1] = 'x';
format_integer(buffer + 2, sizeof(buffer) - 2, value, 'x');
- } else if (c == 'd' || c == 'i' || c == 'o' || c == 'x' || c == 'X') {
+ } else if (c == 'd' || c == 'i' || c == 'o' || c == 'u' || c == 'x' || c == 'X') {
/* integers - first read value from stack */
uint64_t value;
int is_signed = (c == 'd' || c == 'i' || c == 'o');
diff --git a/libc/bionic/malloc_debug_check.cpp b/libc/bionic/malloc_debug_check.cpp
index 91cf287..11a6ec1 100644
--- a/libc/bionic/malloc_debug_check.cpp
+++ b/libc/bionic/malloc_debug_check.cpp
@@ -74,6 +74,10 @@
struct hdr_t {
uint32_t tag;
+ void* base; // Always points to the memory allocated using dlmalloc.
+ // For memory allocated in chk_memalign, this value will
+ // not be the same as the location of the start of this
+ // structure.
hdr_t* prev;
hdr_t* next;
uintptr_t bt[MAX_BACKTRACE_DEPTH];
@@ -82,7 +86,7 @@
int freed_bt_depth;
size_t size;
char front_guard[FRONT_GUARD_LEN];
-} __attribute__((packed));
+} __attribute__((packed, aligned(MALLOC_ALIGNMENT)));
struct ftr_t {
char rear_guard[REAR_GUARD_LEN];
@@ -100,21 +104,26 @@
return reinterpret_cast<hdr_t*>(user) - 1;
}
+static inline const hdr_t* const_meta(const void* user) {
+ return reinterpret_cast<const hdr_t*>(user) - 1;
+}
+
+
static unsigned gAllocatedBlockCount;
-static hdr_t *tail;
-static hdr_t *head;
+static hdr_t* tail;
+static hdr_t* head;
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
static unsigned backlog_num;
-static hdr_t *backlog_tail;
-static hdr_t *backlog_head;
+static hdr_t* backlog_tail;
+static hdr_t* backlog_head;
static pthread_mutex_t backlog_lock = PTHREAD_MUTEX_INITIALIZER;
-static inline void init_front_guard(hdr_t *hdr) {
+static inline void init_front_guard(hdr_t* hdr) {
memset(hdr->front_guard, FRONT_GUARD, FRONT_GUARD_LEN);
}
-static inline bool is_front_guard_valid(hdr_t *hdr) {
+static inline bool is_front_guard_valid(hdr_t* hdr) {
for (size_t i = 0; i < FRONT_GUARD_LEN; i++) {
if (hdr->front_guard[i] != FRONT_GUARD) {
return 0;
@@ -123,12 +132,12 @@
return 1;
}
-static inline void init_rear_guard(hdr_t *hdr) {
+static inline void init_rear_guard(hdr_t* hdr) {
ftr_t* ftr = to_ftr(hdr);
memset(ftr->rear_guard, REAR_GUARD, REAR_GUARD_LEN);
}
-static inline bool is_rear_guard_valid(hdr_t *hdr) {
+static inline bool is_rear_guard_valid(hdr_t* hdr) {
unsigned i;
int valid = 1;
int first_mismatch = -1;
@@ -149,7 +158,7 @@
return valid;
}
-static inline void add_locked(hdr_t *hdr, hdr_t **tail, hdr_t **head) {
+static inline void add_locked(hdr_t* hdr, hdr_t** tail, hdr_t** head) {
hdr->prev = NULL;
hdr->next = *head;
if (*head)
@@ -159,7 +168,7 @@
*head = hdr;
}
-static inline int del_locked(hdr_t *hdr, hdr_t **tail, hdr_t **head) {
+static inline int del_locked(hdr_t* hdr, hdr_t** tail, hdr_t** head) {
if (hdr->prev) {
hdr->prev->next = hdr->next;
} else {
@@ -173,7 +182,7 @@
return 0;
}
-static inline void add(hdr_t *hdr, size_t size) {
+static inline void add(hdr_t* hdr, size_t size) {
ScopedPthreadMutexLocker locker(&lock);
hdr->tag = ALLOCATION_TAG;
hdr->size = size;
@@ -183,7 +192,7 @@
add_locked(hdr, &tail, &head);
}
-static inline int del(hdr_t *hdr) {
+static inline int del(hdr_t* hdr) {
if (hdr->tag != ALLOCATION_TAG) {
return -1;
}
@@ -194,13 +203,13 @@
return 0;
}
-static inline void poison(hdr_t *hdr) {
+static inline void poison(hdr_t* hdr) {
memset(user(hdr), FREE_POISON, hdr->size);
}
-static int was_used_after_free(hdr_t *hdr) {
+static int was_used_after_free(hdr_t* hdr) {
unsigned i;
- const char *data = (const char *)user(hdr);
+ const char* data = reinterpret_cast<const char *>(user(hdr));
for (i = 0; i < hdr->size; i++)
if (data[i] != FREE_POISON)
return 1;
@@ -208,7 +217,7 @@
}
/* returns 1 if valid, *safe == 1 if safe to dump stack */
-static inline int check_guards(hdr_t *hdr, int *safe) {
+static inline int check_guards(hdr_t* hdr, int* safe) {
*safe = 1;
if (!is_front_guard_valid(hdr)) {
if (hdr->front_guard[0] == FRONT_GUARD) {
@@ -233,7 +242,7 @@
}
/* returns 1 if valid, *safe == 1 if safe to dump stack */
-static inline int check_allocation_locked(hdr_t *hdr, int *safe) {
+static inline int check_allocation_locked(hdr_t* hdr, int* safe) {
int valid = 1;
*safe = 1;
@@ -270,9 +279,9 @@
return valid;
}
-static inline int del_and_check_locked(hdr_t *hdr,
- hdr_t **tail, hdr_t **head, unsigned *cnt,
- int *safe) {
+static inline int del_and_check_locked(hdr_t* hdr,
+ hdr_t** tail, hdr_t** head, unsigned* cnt,
+ int* safe) {
int valid = check_allocation_locked(hdr, safe);
if (safe) {
(*cnt)--;
@@ -281,7 +290,7 @@
return valid;
}
-static inline void del_from_backlog_locked(hdr_t *hdr) {
+static inline void del_from_backlog_locked(hdr_t* hdr) {
int safe;
del_and_check_locked(hdr,
&backlog_tail, &backlog_head, &backlog_num,
@@ -289,17 +298,17 @@
hdr->tag = 0; /* clear the tag */
}
-static inline void del_from_backlog(hdr_t *hdr) {
+static inline void del_from_backlog(hdr_t* hdr) {
ScopedPthreadMutexLocker locker(&backlog_lock);
del_from_backlog_locked(hdr);
}
-static inline int del_leak(hdr_t *hdr, int *safe) {
+static inline int del_leak(hdr_t* hdr, int* safe) {
ScopedPthreadMutexLocker locker(&lock);
return del_and_check_locked(hdr, &tail, &head, &gAllocatedBlockCount, safe);
}
-static inline void add_to_backlog(hdr_t *hdr) {
+static inline void add_to_backlog(hdr_t* hdr) {
ScopedPthreadMutexLocker locker(&backlog_lock);
hdr->tag = BACKLOG_TAG;
backlog_num++;
@@ -307,9 +316,9 @@
poison(hdr);
/* If we've exceeded the maximum backlog, clear it up */
while (backlog_num > gMallocDebugBacklog) {
- hdr_t *gone = backlog_tail;
+ hdr_t* gone = backlog_tail;
del_from_backlog_locked(gone);
- dlfree(gone);
+ dlfree(gone->base);
}
}
@@ -318,6 +327,7 @@
hdr_t* hdr = static_cast<hdr_t*>(dlmalloc(sizeof(hdr_t) + size + sizeof(ftr_t)));
if (hdr) {
+ hdr->base = hdr;
hdr->bt_depth = get_backtrace(hdr->bt, MAX_BACKTRACE_DEPTH);
add(hdr, size);
return user(hdr);
@@ -325,13 +335,44 @@
return NULL;
}
-extern "C" void* chk_memalign(size_t, size_t bytes) {
-// log_message("%s: %s\n", __FILE__, __FUNCTION__);
- // XXX: it's better to use malloc, than being wrong
- return chk_malloc(bytes);
+extern "C" void* chk_memalign(size_t alignment, size_t bytes) {
+ if (alignment <= MALLOC_ALIGNMENT) {
+ return chk_malloc(bytes);
+ }
+
+ // Make the alignment a power of two.
+ if (alignment & (alignment-1)) {
+ alignment = 1L << (31 - __builtin_clz(alignment));
+ }
+
+ // here, alignment is at least MALLOC_ALIGNMENT<<1 bytes
+ // we will align by at least MALLOC_ALIGNMENT bytes
+ // and at most alignment-MALLOC_ALIGNMENT bytes
+ size_t size = (alignment-MALLOC_ALIGNMENT) + bytes;
+ if (size < bytes) { // Overflow.
+ return NULL;
+ }
+
+ void* base = dlmalloc(sizeof(hdr_t) + size + sizeof(ftr_t));
+ if (base != NULL) {
+ // Check that the actual pointer that will be returned is aligned
+ // properly.
+ uintptr_t ptr = reinterpret_cast<uintptr_t>(user(reinterpret_cast<hdr_t*>(base)));
+ if ((ptr % alignment) != 0) {
+ // Align the pointer.
+ ptr += ((-ptr) % alignment);
+ }
+
+ hdr_t* hdr = meta(reinterpret_cast<void*>(ptr));
+ hdr->base = base;
+ hdr->bt_depth = get_backtrace(hdr->bt, MAX_BACKTRACE_DEPTH);
+ add(hdr, bytes);
+ return user(hdr);
+ }
+ return base;
}
-extern "C" void chk_free(void *ptr) {
+extern "C" void chk_free(void* ptr) {
// log_message("%s: %s\n", __FILE__, __FUNCTION__);
if (!ptr) /* ignore free(NULL) */
@@ -366,7 +407,7 @@
}
}
-extern "C" void *chk_realloc(void *ptr, size_t size) {
+extern "C" void* chk_realloc(void* ptr, size_t size) {
// log_message("%s: %s\n", __FILE__, __FUNCTION__);
if (!ptr) {
@@ -414,8 +455,23 @@
}
}
- hdr = static_cast<hdr_t*>(dlrealloc(hdr, sizeof(hdr_t) + size + sizeof(ftr_t)));
+ if (hdr->base != hdr) {
+ // An allocation from memalign, so create another allocation and
+ // copy the data out.
+ void* newMem = dlmalloc(sizeof(hdr_t) + size + sizeof(ftr_t));
+ if (newMem) {
+ memcpy(newMem, hdr, sizeof(hdr_t) + hdr->size);
+ dlfree(hdr->base);
+ hdr = static_cast<hdr_t*>(newMem);
+ } else {
+ dlfree(hdr->base);
+ hdr = NULL;
+ }
+ } else {
+ hdr = static_cast<hdr_t*>(dlrealloc(hdr, sizeof(hdr_t) + size + sizeof(ftr_t)));
+ }
if (hdr) {
+ hdr->base = hdr;
hdr->bt_depth = get_backtrace(hdr->bt, MAX_BACKTRACE_DEPTH);
add(hdr, size);
return user(hdr);
@@ -424,11 +480,12 @@
return NULL;
}
-extern "C" void *chk_calloc(int nmemb, size_t size) {
+extern "C" void* chk_calloc(int nmemb, size_t size) {
// log_message("%s: %s\n", __FILE__, __FUNCTION__);
size_t total_size = nmemb * size;
hdr_t* hdr = static_cast<hdr_t*>(dlcalloc(1, sizeof(hdr_t) + total_size + sizeof(ftr_t)));
if (hdr) {
+ hdr->base = hdr;
hdr->bt_depth = get_backtrace(hdr->bt, MAX_BACKTRACE_DEPTH);
add(hdr, total_size);
return user(hdr);
@@ -436,6 +493,18 @@
return NULL;
}
+extern "C" size_t chk_malloc_usable_size(const void* ptr) {
+ // dlmalloc_usable_size returns 0 for NULL and unknown blocks.
+ if (ptr == NULL)
+ return 0;
+
+ const hdr_t* hdr = const_meta(ptr);
+
+ // The sentinel tail is written just after the request block bytes
+ // so there is no extra room we can report here.
+ return hdr->size;
+}
+
static void ReportMemoryLeaks() {
// We only track leaks at level 10.
if (gMallocDebugLevel != 10) {
diff --git a/libc/bionic/malloc_debug_common.cpp b/libc/bionic/malloc_debug_common.cpp
index 9cc84c3..ccceb14 100644
--- a/libc/bionic/malloc_debug_common.cpp
+++ b/libc/bionic/malloc_debug_common.cpp
@@ -190,10 +190,6 @@
return dlmallinfo();
}
-extern "C" size_t malloc_usable_size(const void* mem) {
- return dlmalloc_usable_size(mem);
-}
-
extern "C" void* valloc(size_t bytes) {
return dlvalloc(bytes);
}
@@ -215,8 +211,9 @@
/* Table for dispatching malloc calls, initialized with default dispatchers. */
extern const MallocDebug __libc_malloc_default_dispatch;
-const MallocDebug __libc_malloc_default_dispatch __attribute__((aligned(32))) = {
- dlmalloc, dlfree, dlcalloc, dlrealloc, dlmemalign
+const MallocDebug __libc_malloc_default_dispatch __attribute__((aligned(32))) =
+{
+ dlmalloc, dlfree, dlcalloc, dlrealloc, dlmemalign, dlmalloc_usable_size,
};
/* Selector of dispatch table to use for dispatching malloc calls. */
@@ -242,6 +239,10 @@
return __libc_malloc_dispatch->memalign(alignment, bytes);
}
+extern "C" size_t malloc_usable_size(const void* mem) {
+ return __libc_malloc_dispatch->malloc_usable_size(mem);
+}
+
/* We implement malloc debugging only in libc.so, so code below
* must be excluded if we compile this file for static libc.a
*/
@@ -253,7 +254,7 @@
/* Table for dispatching malloc calls, depending on environment. */
static MallocDebug gMallocUse __attribute__((aligned(32))) = {
- dlmalloc, dlfree, dlcalloc, dlrealloc, dlmemalign
+ dlmalloc, dlfree, dlcalloc, dlrealloc, dlmemalign, dlmalloc_usable_size
};
extern const char* __progname;
@@ -276,15 +277,10 @@
* Actual functionality for debug levels 1-10 is implemented in
* libc_malloc_debug_leak.so, while functionality for emultor's instrumented
* allocations is implemented in libc_malloc_debug_qemu.so and can be run inside
- * the emulator only.
+ * the emulator only.
*/
static void* libc_malloc_impl_handle = NULL;
-// This must match the alignment used by dlmalloc.
-#ifndef MALLOC_ALIGNMENT
-#define MALLOC_ALIGNMENT ((size_t)(2 * sizeof(void *)))
-#endif
-
/* This variable is set to the value of property libc.debug.malloc.backlog,
* when the value of libc.debug.malloc = 10. It determines the size of the
* backlog we use to detect multiple frees. If the property is not set, the
@@ -296,41 +292,26 @@
/* The value of libc.debug.malloc. */
int gMallocDebugLevel;
-static void InitMalloc(MallocDebug* table, const char* prefix) {
- __libc_format_log(ANDROID_LOG_INFO, "libc", "%s: using libc.debug.malloc %d (%s)\n",
- __progname, gMallocDebugLevel, prefix);
+template<typename FunctionType>
+void InitMallocFunction(void* malloc_impl_handler, FunctionType* func, const char* prefix, const char* suffix) {
+ char symbol[128];
+ snprintf(symbol, sizeof(symbol), "%s_%s", prefix, suffix);
+ *func = reinterpret_cast<FunctionType>(dlsym(malloc_impl_handler, symbol));
+ if (*func == NULL) {
+ error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
+ }
+}
- char symbol[128];
+static void InitMalloc(void* malloc_impl_handler, MallocDebug* table, const char* prefix) {
+ __libc_format_log(ANDROID_LOG_INFO, "libc", "%s: using libc.debug.malloc %d (%s)\n",
+ __progname, gMallocDebugLevel, prefix);
- snprintf(symbol, sizeof(symbol), "%s_malloc", prefix);
- table->malloc = reinterpret_cast<MallocDebugMalloc>(dlsym(libc_malloc_impl_handle, symbol));
- if (table->malloc == NULL) {
- error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
- }
-
- snprintf(symbol, sizeof(symbol), "%s_free", prefix);
- table->free = reinterpret_cast<MallocDebugFree>(dlsym(libc_malloc_impl_handle, symbol));
- if (table->free == NULL) {
- error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
- }
-
- snprintf(symbol, sizeof(symbol), "%s_calloc", prefix);
- table->calloc = reinterpret_cast<MallocDebugCalloc>(dlsym(libc_malloc_impl_handle, symbol));
- if (table->calloc == NULL) {
- error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
- }
-
- snprintf(symbol, sizeof(symbol), "%s_realloc", prefix);
- table->realloc = reinterpret_cast<MallocDebugRealloc>(dlsym(libc_malloc_impl_handle, symbol));
- if (table->realloc == NULL) {
- error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
- }
-
- snprintf(symbol, sizeof(symbol), "%s_memalign", prefix);
- table->memalign = reinterpret_cast<MallocDebugMemalign>(dlsym(libc_malloc_impl_handle, symbol));
- if (table->memalign == NULL) {
- error_log("%s: dlsym(\"%s\") failed", __progname, symbol);
- }
+ InitMallocFunction<MallocDebugMalloc>(malloc_impl_handler, &table->malloc, prefix, "malloc");
+ InitMallocFunction<MallocDebugFree>(malloc_impl_handler, &table->free, prefix, "free");
+ InitMallocFunction<MallocDebugCalloc>(malloc_impl_handler, &table->calloc, prefix, "calloc");
+ InitMallocFunction<MallocDebugRealloc>(malloc_impl_handler, &table->realloc, prefix, "realloc");
+ InitMallocFunction<MallocDebugMemalign>(malloc_impl_handler, &table->memalign, prefix, "memalign");
+ InitMallocFunction<MallocDebugMallocUsableSize>(malloc_impl_handler, &table->malloc_usable_size, prefix, "malloc_usable_size");
}
/* Initializes memory allocation framework once per process. */
@@ -422,24 +403,24 @@
}
// Load .so that implements the required malloc debugging functionality.
- libc_malloc_impl_handle = dlopen(so_name, RTLD_LAZY);
- if (libc_malloc_impl_handle == NULL) {
+ void* malloc_impl_handle = dlopen(so_name, RTLD_LAZY);
+ if (malloc_impl_handle == NULL) {
error_log("%s: Missing module %s required for malloc debug level %d: %s",
__progname, so_name, gMallocDebugLevel, dlerror());
return;
}
// Initialize malloc debugging in the loaded module.
- malloc_debug_initialize = reinterpret_cast<MallocDebugInit>(dlsym(libc_malloc_impl_handle,
+ malloc_debug_initialize = reinterpret_cast<MallocDebugInit>(dlsym(malloc_impl_handle,
"malloc_debug_initialize"));
if (malloc_debug_initialize == NULL) {
error_log("%s: Initialization routine is not found in %s\n",
__progname, so_name);
- dlclose(libc_malloc_impl_handle);
+ dlclose(malloc_impl_handle);
return;
}
if (malloc_debug_initialize() == -1) {
- dlclose(libc_malloc_impl_handle);
+ dlclose(malloc_impl_handle);
return;
}
@@ -447,34 +428,35 @@
// For memory checker we need to do extra initialization.
typedef int (*MemCheckInit)(int, const char*);
MemCheckInit memcheck_initialize =
- reinterpret_cast<MemCheckInit>(dlsym(libc_malloc_impl_handle,
+ reinterpret_cast<MemCheckInit>(dlsym(malloc_impl_handle,
"memcheck_initialize"));
if (memcheck_initialize == NULL) {
error_log("%s: memcheck_initialize routine is not found in %s\n",
__progname, so_name);
- dlclose(libc_malloc_impl_handle);
+ dlclose(malloc_impl_handle);
return;
}
if (memcheck_initialize(MALLOC_ALIGNMENT, memcheck_tracing)) {
- dlclose(libc_malloc_impl_handle);
+ dlclose(malloc_impl_handle);
return;
}
}
+
// Initialize malloc dispatch table with appropriate routines.
switch (gMallocDebugLevel) {
case 1:
- InitMalloc(&gMallocUse, "leak");
+ InitMalloc(malloc_impl_handle, &gMallocUse, "leak");
break;
case 5:
- InitMalloc(&gMallocUse, "fill");
+ InitMalloc(malloc_impl_handle, &gMallocUse, "fill");
break;
case 10:
- InitMalloc(&gMallocUse, "chk");
+ InitMalloc(malloc_impl_handle, &gMallocUse, "chk");
break;
case 20:
- InitMalloc(&gMallocUse, "qemu_instrumented");
+ InitMalloc(malloc_impl_handle, &gMallocUse, "qemu_instrumented");
break;
default:
break;
@@ -485,13 +467,14 @@
(gMallocUse.free == NULL) ||
(gMallocUse.calloc == NULL) ||
(gMallocUse.realloc == NULL) ||
- (gMallocUse.memalign == NULL)) {
+ (gMallocUse.memalign == NULL) ||
+ (gMallocUse.malloc_usable_size == NULL)) {
error_log("%s: some symbols for libc.debug.malloc level %d were not found (see above)",
__progname, gMallocDebugLevel);
- dlclose(libc_malloc_impl_handle);
- libc_malloc_impl_handle = NULL;
+ dlclose(malloc_impl_handle);
} else {
__libc_malloc_dispatch = &gMallocUse;
+ libc_malloc_impl_handle = malloc_impl_handle;
}
}
diff --git a/libc/bionic/malloc_debug_common.h b/libc/bionic/malloc_debug_common.h
index 12d0e65..a3f9909 100644
--- a/libc/bionic/malloc_debug_common.h
+++ b/libc/bionic/malloc_debug_common.h
@@ -45,6 +45,11 @@
#define MAX_SIZE_T (~(size_t)0)
+// This must match the alignment used by dlmalloc.
+#ifndef MALLOC_ALIGNMENT
+#define MALLOC_ALIGNMENT ((size_t)(2 * sizeof(void *)))
+#endif
+
// =============================================================================
// Structures
// =============================================================================
@@ -71,12 +76,14 @@
typedef void* (*MallocDebugCalloc)(size_t, size_t);
typedef void* (*MallocDebugRealloc)(void*, size_t);
typedef void* (*MallocDebugMemalign)(size_t, size_t);
+typedef size_t (*MallocDebugMallocUsableSize)(const void*);
struct MallocDebug {
MallocDebugMalloc malloc;
MallocDebugFree free;
MallocDebugCalloc calloc;
MallocDebugRealloc realloc;
MallocDebugMemalign memalign;
+ MallocDebugMallocUsableSize malloc_usable_size;
};
/* Malloc debugging initialization and finalization routines.
diff --git a/libc/bionic/malloc_debug_leak.cpp b/libc/bionic/malloc_debug_leak.cpp
index 2db8a1f..45b45c2 100644
--- a/libc/bionic/malloc_debug_leak.cpp
+++ b/libc/bionic/malloc_debug_leak.cpp
@@ -67,9 +67,6 @@
// stack trace functions
// =============================================================================
-#ifndef MALLOC_ALIGNMENT
-#define MALLOC_ALIGNMENT ((size_t)8U)
-#endif
#define GUARD 0x48151642
#define DEBUG 0
@@ -80,12 +77,16 @@
struct AllocationEntry {
HashEntry* entry;
uint32_t guard;
-};
+} __attribute__((aligned(MALLOC_ALIGNMENT)));
-static AllocationEntry* to_header(void* mem) {
+static inline AllocationEntry* to_header(void* mem) {
return reinterpret_cast<AllocationEntry*>(mem) - 1;
}
+static inline const AllocationEntry* const_to_header(const void* mem) {
+ return reinterpret_cast<const AllocationEntry*>(mem) - 1;
+}
+
// =============================================================================
// Hash Table functions
// =============================================================================
@@ -229,17 +230,16 @@
}
extern "C" void* fill_realloc(void* mem, size_t bytes) {
- void* buffer = fill_malloc(bytes);
- if (mem == NULL) {
- return buffer;
+ size_t oldSize = dlmalloc_usable_size(mem);
+ void* newMem = dlrealloc(mem, bytes);
+ if (newMem) {
+ // If this is larger than before, fill the extra with our pattern.
+ size_t newSize = dlmalloc_usable_size(newMem);
+ if (newSize > oldSize) {
+ memset(reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(newMem)+oldSize), CHK_FILL_FREE, newSize-oldSize);
+ }
}
- if (buffer) {
- size_t old_size = dlmalloc_usable_size(mem);
- size_t size = (bytes < old_size)?(bytes):(old_size);
- memcpy(buffer, mem, size);
- fill_free(mem);
- }
- return buffer;
+ return newMem;
}
extern "C" void* fill_memalign(size_t alignment, size_t bytes) {
@@ -250,11 +250,17 @@
return buffer;
}
+extern "C" size_t fill_malloc_usable_size(const void* mem) {
+ // Since we didn't allocate extra bytes before or after, we can
+ // report the normal usable size here.
+ return dlmalloc_usable_size(mem);
+}
+
// =============================================================================
// malloc leak functions
// =============================================================================
-static void* MEMALIGN_GUARD = reinterpret_cast<void*>(0xA1A41520);
+static uint32_t MEMALIGN_GUARD = 0xA1A41520;
extern "C" void* leak_malloc(size_t bytes) {
// allocate enough space infront of the allocation to store the pointer for
@@ -296,9 +302,10 @@
if (header->guard != GUARD) {
// could be a memaligned block
- if (reinterpret_cast<void**>(mem)[-1] == MEMALIGN_GUARD) {
- mem = reinterpret_cast<void**>(mem)[-2];
- header = to_header(mem);
+ if (header->guard == MEMALIGN_GUARD) {
+ // For memaligned blocks, header->entry points to the memory
+ // allocated through leak_malloc.
+ header = to_header(header->entry);
}
}
@@ -338,19 +345,26 @@
if (oldMem == NULL) {
return leak_malloc(bytes);
}
+
void* newMem = NULL;
AllocationEntry* header = to_header(oldMem);
- if (header && header->guard == GUARD) {
- size_t oldSize = header->entry->size & ~SIZE_FLAG_MASK;
- newMem = leak_malloc(bytes);
- if (newMem != NULL) {
- size_t copySize = (oldSize <= bytes) ? oldSize : bytes;
- memcpy(newMem, oldMem, copySize);
- leak_free(oldMem);
- }
- } else {
- newMem = dlrealloc(oldMem, bytes);
+ if (header->guard == MEMALIGN_GUARD) {
+ // Get the real header.
+ header = to_header(header->entry);
+ } else if (header->guard != GUARD) {
+ debug_log("WARNING bad header guard: '0x%x'! and invalid entry: %p\n",
+ header->guard, header->entry);
+ return NULL;
}
+
+ newMem = leak_malloc(bytes);
+ if (newMem != NULL) {
+ size_t oldSize = header->entry->size & ~SIZE_FLAG_MASK;
+ size_t copySize = (oldSize <= bytes) ? oldSize : bytes;
+ memcpy(newMem, oldMem, copySize);
+ }
+ leak_free(oldMem);
+
return newMem;
}
@@ -375,7 +389,7 @@
void* base = leak_malloc(size);
if (base != NULL) {
- intptr_t ptr = reinterpret_cast<intptr_t>(base);
+ uintptr_t ptr = reinterpret_cast<uintptr_t>(base);
if ((ptr % alignment) == 0) {
return base;
}
@@ -383,11 +397,38 @@
// align the pointer
ptr += ((-ptr) % alignment);
- // there is always enough space for the base pointer and the guard
- reinterpret_cast<void**>(ptr)[-1] = MEMALIGN_GUARD;
- reinterpret_cast<void**>(ptr)[-2] = base;
+ // Already allocated enough space for the header. This assumes
+ // that the malloc alignment is at least 8, otherwise, this is
+ // not guaranteed to have the space for the header.
+ AllocationEntry* header = to_header(reinterpret_cast<void*>(ptr));
+ header->guard = MEMALIGN_GUARD;
+ header->entry = reinterpret_cast<HashEntry*>(base);
return reinterpret_cast<void*>(ptr);
}
return base;
}
+
+extern "C" size_t leak_malloc_usable_size(const void* mem) {
+ if (mem != NULL) {
+ // Check the guard to make sure it is valid.
+ const AllocationEntry* header = const_to_header((void*)mem);
+
+ if (header->guard == MEMALIGN_GUARD) {
+ // If this is a memalign'd pointer, then grab the header from
+ // entry.
+ header = const_to_header(header->entry);
+ } else if (header->guard != GUARD) {
+ debug_log("WARNING bad header guard: '0x%x'! and invalid entry: %p\n",
+ header->guard, header->entry);
+ return 0;
+ }
+
+ size_t ret = dlmalloc_usable_size(header);
+ if (ret != 0) {
+ // The usable area starts at 'mem' and stops at 'header+ret'.
+ return reinterpret_cast<uintptr_t>(header) + ret - reinterpret_cast<uintptr_t>(mem);
+ }
+ }
+ return 0;
+}
diff --git a/libc/bionic/malloc_debug_qemu.cpp b/libc/bionic/malloc_debug_qemu.cpp
index 34ddb87..4c666a9 100644
--- a/libc/bionic/malloc_debug_qemu.cpp
+++ b/libc/bionic/malloc_debug_qemu.cpp
@@ -137,7 +137,7 @@
* will respond with information about allocated block that contains this
* pointer.
*/
- void* ptr;
+ const void* ptr;
/* Id of the process that initialized libc instance, in which this query
* is called. This field is used by the emulator to report errors in
@@ -469,7 +469,7 @@
* Return:
* Zero on success, or -1 on failure.
*/
-static inline int query_qemu_malloc_info(void* ptr, MallocDesc* desc, uint32_t routine) {
+static inline int query_qemu_malloc_info(const void* ptr, MallocDesc* desc, uint32_t routine) {
volatile MallocDescQuery query;
query.ptr = ptr;
@@ -574,11 +574,12 @@
// API routines
// =============================================================================
-void* qemu_instrumented_malloc(size_t bytes);
-void qemu_instrumented_free(void* mem);
-void* qemu_instrumented_calloc(size_t n_elements, size_t elem_size);
-void* qemu_instrumented_realloc(void* mem, size_t bytes);
-void* qemu_instrumented_memalign(size_t alignment, size_t bytes);
+extern "C" void* qemu_instrumented_malloc(size_t bytes);
+extern "C" void qemu_instrumented_free(void* mem);
+extern "C" void* qemu_instrumented_calloc(size_t n_elements, size_t elem_size);
+extern "C" void* qemu_instrumented_realloc(void* mem, size_t bytes);
+extern "C" void* qemu_instrumented_memalign(size_t alignment, size_t bytes);
+extern "C" size_t qemu_instrumented_malloc_usable_size(const void* mem);
/* Initializes malloc debugging instrumentation for the emulator.
* This routine is called from malloc_init_impl routine implemented in
@@ -589,7 +590,7 @@
* Return:
* 0 on success, or -1 on failure.
*/
-int malloc_debug_initialize() {
+extern "C" int malloc_debug_initialize() {
/* We will be using emulator's magic page to report memory allocation
* activities. In essence, what magic page does, it translates writes to
* the memory mapped spaces into writes to an I/O port that emulator
@@ -627,7 +628,7 @@
* Return:
* 0 on success, or -1 on failure.
*/
-int memcheck_initialize(int alignment, const char* memcheck_param) {
+extern "C" int memcheck_initialize(int alignment, const char* memcheck_param) {
malloc_alignment = alignment;
/* Parse -memcheck parameter for the guest tracing flags. */
@@ -673,7 +674,7 @@
* bytes (plus prefix, and suffix guards), and report allocation to the
* emulator.
*/
-void* qemu_instrumented_malloc(size_t bytes) {
+extern "C" void* qemu_instrumented_malloc(size_t bytes) {
MallocDesc desc;
/* Initialize block descriptor and allocate memory. Note that dlmalloc
@@ -708,7 +709,7 @@
* Primary responsibility of this routine is to free requested memory, and
* report free block to the emulator.
*/
-void qemu_instrumented_free(void* mem) {
+extern "C" void qemu_instrumented_free(void* mem) {
MallocDesc desc;
if (mem == NULL) {
@@ -751,7 +752,7 @@
/* This routine serves as entry point for 'calloc'.
* This routine behaves similarly to qemu_instrumented_malloc.
*/
-void* qemu_instrumented_calloc(size_t n_elements, size_t elem_size) {
+extern "C" void* qemu_instrumented_calloc(size_t n_elements, size_t elem_size) {
if (n_elements == 0 || elem_size == 0) {
// Just let go zero bytes allocation.
qemu_info_log("::: <libc_pid=%03u, pid=%03u>: Zero calloc redir to malloc",
@@ -823,7 +824,7 @@
* allocation, but overall it doesn't seem to matter, as caller of realloc
* should not expect that pointer returned after shrinking will remain the same.
*/
-void* qemu_instrumented_realloc(void* mem, size_t bytes) {
+extern "C" void* qemu_instrumented_realloc(void* mem, size_t bytes) {
MallocDesc new_desc;
MallocDesc cur_desc;
size_t to_copy;
@@ -927,7 +928,7 @@
/* This routine serves as entry point for 'memalign'.
* This routine behaves similarly to qemu_instrumented_malloc.
*/
-void* qemu_instrumented_memalign(size_t alignment, size_t bytes) {
+extern "C" void* qemu_instrumented_memalign(size_t alignment, size_t bytes) {
MallocDesc desc;
if (bytes == 0) {
@@ -967,3 +968,27 @@
malloc_pid, getpid(), alignment, bytes);
return mallocdesc_user_ptr(&desc);
}
+
+extern "C" size_t qemu_instrumented_malloc_usable_size(const void* mem) {
+ MallocDesc cur_desc;
+
+ // Query emulator for the reallocating block information.
+ if (query_qemu_malloc_info(mem, &cur_desc, 2)) {
+ // Note that this violation should be already caught in the emulator.
+ error_log("<libc_pid=%03u, pid=%03u>: malloc_usable_size(%p) query_info failed.",
+ malloc_pid, getpid(), mem);
+ return 0;
+ }
+
+ /* Make sure that reallocating pointer value is what we would expect
+ * for this memory block. Note that this violation should be already caught
+ * in the emulator.*/
+ if (mem != mallocdesc_user_ptr(&cur_desc)) {
+ log_mdesc(error, &cur_desc, "<libc_pid=%03u, pid=%03u>: malloc_usable_size(%p) is invalid for ",
+ malloc_pid, getpid(), mem);
+ return 0;
+ }
+
+ /* during instrumentation, we can't really report anything more than requested_bytes */
+ return cur_desc.requested_bytes;
+}