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Merge memory checking functionality from sandbox
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Change-Id: I304c789a752c9f4af4944ca14b9bf1e7644da15a
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Vladimir Chtchetkine committed Feb 16, 2010
1 parent 5c73464 commit 75fba68
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Showing 5 changed files with 1,068 additions and 54 deletions.
1 change: 1 addition & 0 deletions .gitignore
@@ -1,2 +1,3 @@
*.pyc
*.*~
libc/kernel/original
122 changes: 89 additions & 33 deletions libc/bionic/malloc_debug_common.c
Expand Up @@ -27,8 +27,8 @@
*/

/*
* Contains definition of global variables and implementation of routines
* that are used by malloc leak detection code and other components in
* Contains definition of structures, global variables, and implementation of
* routines that are used by malloc leak detection code and other components in
* the system. The trick is that some components expect these data and
* routines to be defined / implemented in libc.so library, regardless
* whether or not MALLOC_LEAK_CHECK macro is defined. To make things even
Expand Down Expand Up @@ -237,11 +237,11 @@ void* memalign(size_t alignment, size_t bytes) {
// =============================================================================

#define debug_log(format, ...) \
__libc_android_log_print(ANDROID_LOG_DEBUG, "libc", (format), ##__VA_ARGS__ )
__libc_android_log_print(ANDROID_LOG_DEBUG, "libc", (format), ##__VA_ARGS__ )
#define error_log(format, ...) \
__libc_android_log_print(ANDROID_LOG_ERROR, "libc", (format), ##__VA_ARGS__ )
__libc_android_log_print(ANDROID_LOG_ERROR, "libc", (format), ##__VA_ARGS__ )
#define info_log(format, ...) \
__libc_android_log_print(ANDROID_LOG_INFO, "libc", (format), ##__VA_ARGS__ )
__libc_android_log_print(ANDROID_LOG_INFO, "libc", (format), ##__VA_ARGS__ )

/* Table for dispatching malloc calls, depending on environment. */
static MallocDebug gMallocUse __attribute__((aligned(32))) = {
Expand All @@ -259,43 +259,64 @@ extern char* __progname;
* CHK_SENTINEL_VALUE, and CHK_FILL_FREE macros.
* 10 - For adding pre-, and post- allocation stubs in order to detect
* buffer overruns.
* 20 - For enabling emulator memory allocation instrumentation detecting
* memory leaks and buffer overruns.
* Note that emulator's memory allocation instrumentation is not controlled by
* libc.debug.malloc value, but rather by emulator, started with -memcheck
* option. Note also, that if emulator has started with -memcheck option,
* emulator's instrumented memory allocation will take over value saved in
* libc.debug.malloc. In other words, if emulator has started with -memcheck
* option, libc.debug.malloc value is ignored.
* Actual functionality for debug levels 1-10 is implemented in
* libc_malloc_debug_leak.so, while functionality for debug level 20 is
* implemented in libc_malloc_debug_qemu.so and can be run inside the
* emulator only.
* 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.
*/
static void* libc_malloc_impl_handle = NULL;

/* Make sure we have MALLOC_ALIGNMENT that matches the one that is
* used in dlmalloc. Emulator's memchecker needs this value to properly
* align its guarding zones.
*/
#ifndef MALLOC_ALIGNMENT
#define MALLOC_ALIGNMENT ((size_t)8U)
#endif /* MALLOC_ALIGNMENT */

/* Initializes memory allocation framework once per process. */
static void malloc_init_impl(void)
{
const char* so_name = NULL;
unsigned int debug_level = 0;
MallocDebugInit malloc_debug_initialize = NULL;
unsigned int qemu_running = 0;
int len;
unsigned int debug_level = 0;
unsigned int memcheck_enabled = 0;
char env[PROP_VALUE_MAX];
char memcheck_tracing[PROP_VALUE_MAX];

/* Get custom malloc debug level. Note that emulator started with
* memory checking option will have priority over debug level set in
* libc.debug.malloc system property. */
if (__system_property_get("ro.kernel.qemu", env) && atoi(env)) {
qemu_running = 1;
if (__system_property_get("ro.kernel.memcheck", memcheck_tracing)) {
if (memcheck_tracing[0] != '0') {
// Emulator has started with memory tracing enabled. Enforce it.
debug_level = 20;
memcheck_enabled = 1;
}
}
}

// Get custom malloc debug level.
len = __system_property_get("libc.debug.malloc", env);
if (len) {
/* If debug level has not been set by memcheck option in the emulator,
* lets grab it from libc.debug.malloc system property. */
if (!debug_level && __system_property_get("libc.debug.malloc", env)) {
debug_level = atoi(env);
}

/* Debug level 0 means that we should use dlxxx allocation
* routines (default).
*/
* routines (default). */
if (!debug_level) {
return;
}

// Get emulator running status.
len = __system_property_get("ro.kernel.qemu", env);
if (len) {
qemu_running = atoi(env);
}

// Lets see which .so must be loaded for the requested debug level
switch (debug_level) {
case 1:
Expand All @@ -304,17 +325,23 @@ static void malloc_init_impl(void)
so_name = "/system/lib/libc_malloc_debug_leak.so";
break;
case 20:
// Quick check: debug level 20 can only be handled in emulator
// Quick check: debug level 20 can only be handled in emulator.
if (!qemu_running) {
info_log("%s: Debug level %d can only be set in emulator\n",
__progname, debug_level);
error_log("%s: Debug level %d can only be set in emulator\n",
__progname, debug_level);
return;
}
// Make sure that memory checking has been enabled in emulator.
if (!memcheck_enabled) {
error_log("%s: Memory checking is not enabled in the emulator\n",
__progname);
return;
}
so_name = "/system/lib/libc_malloc_debug_qemu.so";
break;
default:
info_log("%s: Debug level %d is unknown\n",
__progname, debug_level);
error_log("%s: Debug level %d is unknown\n",
__progname, debug_level);
return;
}

Expand All @@ -326,6 +353,36 @@ static void malloc_init_impl(void)
return;
}

// Initialize malloc debugging in the loaded module.
malloc_debug_initialize =
dlsym(libc_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);
return;
}
if (malloc_debug_initialize()) {
dlclose(libc_malloc_impl_handle);
return;
}

if (debug_level == 20) {
// For memory checker we need to do extra initialization.
int (*memcheck_initialize)(int, const char*) =
dlsym(libc_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);
return;
}
if (memcheck_initialize(MALLOC_ALIGNMENT, memcheck_tracing)) {
dlclose(libc_malloc_impl_handle);
return;
}
}

// Initialize malloc dispatch table with appropriate routines.
switch (debug_level) {
case 1:
Expand Down Expand Up @@ -374,8 +431,8 @@ static void malloc_init_impl(void)
break;
case 20:
__libc_android_log_print(ANDROID_LOG_INFO, "libc",
"%s using MALLOC_DEBUG = %d (instrumented for emulator)\n",
__progname, debug_level);
"%s[%u] using MALLOC_DEBUG = %d (instrumented for emulator)\n",
__progname, getpid(), debug_level);
gMallocUse.malloc =
dlsym(libc_malloc_impl_handle, "qemu_instrumented_malloc");
gMallocUse.free =
Expand Down Expand Up @@ -421,9 +478,8 @@ static pthread_once_t malloc_init_once_ctl = PTHREAD_ONCE_INIT;
*/
void malloc_debug_init(void)
{
/* We need to initialize malloc iff we impelement here custom
* malloc routines (i.e. USE_DL_PREFIX is defined) for libc.so
*/
/* We need to initialize malloc iff we implement here custom
* malloc routines (i.e. USE_DL_PREFIX is defined) for libc.so */
#if defined(USE_DL_PREFIX) && !defined(LIBC_STATIC)
if (pthread_once(&malloc_init_once_ctl, malloc_init_impl)) {
error_log("Unable to initialize malloc_debug component.");
Expand Down
15 changes: 15 additions & 0 deletions libc/bionic/malloc_debug_common.h
Expand Up @@ -70,13 +70,28 @@ struct HashTable {
/* Entry in malloc dispatch table. */
typedef struct MallocDebug MallocDebug;
struct MallocDebug {
/* Address of the actual malloc routine. */
void* (*malloc)(size_t bytes);
/* Address of the actual free routine. */
void (*free)(void* mem);
/* Address of the actual calloc routine. */
void* (*calloc)(size_t n_elements, size_t elem_size);
/* Address of the actual realloc routine. */
void* (*realloc)(void* oldMem, size_t bytes);
/* Address of the actual memalign routine. */
void* (*memalign)(size_t alignment, size_t bytes);
};

/* Malloc debugging initialization routine.
* This routine must be implemented in .so modules that implement malloc
* debugging. This routine is called once per process from malloc_init_impl
* routine implemented in bionic/libc/bionic/malloc_debug_common.c when malloc
* debugging gets initialized for the process.
* Return:
* 0 on success, -1 on failure.
*/
typedef int (*MallocDebugInit)(void);

#ifdef __cplusplus
}; /* end of extern "C" */
#endif
Expand Down
9 changes: 9 additions & 0 deletions libc/bionic/malloc_debug_leak.c
Expand Up @@ -629,3 +629,12 @@ void* leak_memalign(size_t alignment, size_t bytes)
}
return base;
}

/* Initializes malloc debugging framework.
* See comments on MallocDebugInit in malloc_debug_common.h
*/
int malloc_debug_initialize(void)
{
// We don't really have anything that requires initialization here.
return 0;
}

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