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author | Martin Willi <martin@strongswan.org> | 2006-04-10 08:07:38 +0000 |
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committer | Martin Willi <martin@strongswan.org> | 2006-04-10 08:07:38 +0000 |
commit | 5113680f95e522c677cdd37072cfffbdca06831e (patch) | |
tree | 973ac57accbc66b042e5307942c6cbbbf4f19579 /Source/lib/utils/leak_detective.c | |
parent | 6862128151fb78f63685a8da5575783c426d64a7 (diff) | |
download | strongswan-5113680f95e522c677cdd37072cfffbdca06831e.tar.bz2 strongswan-5113680f95e522c677cdd37072cfffbdca06831e.tar.xz |
- split up in libstrong, charon, stroke, testing done
- new leak detective with malloc hook in library
- useable, but needs improvements
- logger_manager has now a single instance per library
- allows use of loggers from any linking prog
- a LOT of other things
Diffstat (limited to 'Source/lib/utils/leak_detective.c')
-rw-r--r-- | Source/lib/utils/leak_detective.c | 382 |
1 files changed, 382 insertions, 0 deletions
diff --git a/Source/lib/utils/leak_detective.c b/Source/lib/utils/leak_detective.c new file mode 100644 index 000000000..67c123be2 --- /dev/null +++ b/Source/lib/utils/leak_detective.c @@ -0,0 +1,382 @@ +/** + * @file leak_detective.c + * + * @brief Implementation of leak_detective_t. + */ + +/* + * Copyright (C) 2006 Martin Willi + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +#include <stddef.h> +#include <pthread.h> +#include <string.h> +#include <stdio.h> +#include <malloc.h> +#include <execinfo.h> +#include <signal.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <dlfcn.h> + +#include "leak_detective.h" + +#include <types.h> + +#ifdef LEAK_DETECTIVE + +/** + * Magic value which helps to detect memory corruption + */ +#define MEMORY_HEADER_MAGIC 0xF1367ADF + + +static void install_hooks(void); +static void uninstall_hooks(void); +static void *malloc_hook(size_t, const void *); +static void *realloc_hook(void *, size_t, const void *); +static void free_hook(void*, const void *); + +typedef struct memory_header_t memory_header_t; + +/** + * Header which is prepended to each allocated memory block + */ +struct memory_header_t { + /** + * Magci byte which must(!) hold MEMORY_HEADER_MAGIC + */ + u_int32_t magic; + + /** + * Number of bytes following after the header + */ + size_t bytes; + + /** + * Stack frames at the time of allocation + */ + void *stack_frames[STACK_FRAMES_COUNT]; + + /** + * Number of stacks frames obtained in stack_frames + */ + int stack_frame_count; + + /** + * Pointer to previous entry in linked list + */ + memory_header_t *previous; + + /** + * Pointer to next entry in linked list + */ + memory_header_t *next; +}; + +/** + * first mem header is just a dummy to chain + * the others on it... + */ +memory_header_t first_header = { + magic: MEMORY_HEADER_MAGIC, + bytes: 0, + stack_frame_count: 0, + previous: NULL, + next: NULL +}; + +/** + * standard hooks, used to temparily remove hooking + */ +void *old_malloc_hook, *old_realloc_hook, *old_free_hook; + + +pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; + + +/** + * log stack frames queried by backtrace() + * TODO: Dump symbols of static functions!!! + */ +void log_stack_frames(void *stack_frames, int stack_frame_count) +{ + char **strings; + size_t i; + + strings = backtrace_symbols (stack_frames, stack_frame_count); + + printf(" dumping %d stack frames.\n", stack_frame_count); + + for (i = 0; i < stack_frame_count; i++) + { + printf (" %s\n", strings[i]); + } + free (strings); +} + +void (*__malloc_initialize_hook) (void) = install_hooks; + +/** + * Installs the malloc hooks, enables leak detection + */ +void install_hooks() +{ + old_malloc_hook = __malloc_hook; + old_realloc_hook = __realloc_hook; + old_free_hook = __free_hook; + __malloc_hook = malloc_hook; + __realloc_hook = realloc_hook; + __free_hook = free_hook; +} + +/** + * Uninstalls the malloc hooks, disables leak detection + */ +void uninstall_hooks() +{ + __malloc_hook = old_malloc_hook; + __free_hook = old_free_hook; +} + +/** + * Hook function for malloc() + */ +static void *malloc_hook(size_t bytes, const void *caller) +{ + memory_header_t *hdr; + + pthread_mutex_lock(&mutex); + uninstall_hooks(); + hdr = malloc(bytes + sizeof(memory_header_t)); + + hdr->magic = MEMORY_HEADER_MAGIC; + hdr->bytes = bytes; + hdr->stack_frame_count = backtrace(hdr->stack_frames, STACK_FRAMES_COUNT); + + /* insert at the beginning of the list */ + hdr->next = first_header.next; + if (hdr->next) + { + hdr->next->previous = hdr; + } + hdr->previous = &first_header; + first_header.next = hdr; + install_hooks(); + pthread_mutex_unlock(&mutex); + return hdr + 1; +} + +/** + * Hook function for free() + */ +static void free_hook(void *ptr, const void *caller) +{ + void *stack_frames[STACK_FRAMES_COUNT]; + int stack_frame_count; + memory_header_t *hdr = ptr - sizeof(memory_header_t); + + /* allow freeing of NULL */ + if (ptr == NULL) + { + return; + } + + pthread_mutex_lock(&mutex); + if (hdr->magic != MEMORY_HEADER_MAGIC) + { + pthread_mutex_unlock(&mutex); + /* TODO: Since we get a lot of theses from the pthread lib, its deactivated for now... */ + return; + printf("freeing of invalid memory (%p)\n", ptr); + stack_frame_count = backtrace(stack_frames, STACK_FRAMES_COUNT); + log_stack_frames(stack_frames, stack_frame_count); + kill(0, SIGSEGV); + return; + } + /* remove magic from hdr */ + hdr->magic = 0; + + /* remove item from list */ + if (hdr->next) + { + hdr->next->previous = hdr->previous; + } + hdr->previous->next = hdr->next; + + uninstall_hooks(); + free(hdr); + install_hooks(); + pthread_mutex_unlock(&mutex); +} + +/** + * Hook function for realloc() + */ +static void *realloc_hook(void *old, size_t bytes, const void *caller) +{ + void *new; + memory_header_t *hdr = old - sizeof(memory_header_t); + void *stack_frames[STACK_FRAMES_COUNT]; + int stack_frame_count; + + /* allow reallocation of NULL */ + if (old == NULL) + { + return malloc_hook(bytes, caller); + } + if (hdr->magic != MEMORY_HEADER_MAGIC) + { + printf("reallocation of invalid memory (%p)\n", old); + stack_frame_count = backtrace(stack_frames, STACK_FRAMES_COUNT); + log_stack_frames(stack_frames, stack_frame_count); + kill(0, SIGSEGV); + return NULL; + } + + /* malloc and free is done with hooks */ + new = malloc_hook(bytes, caller); + memcpy(new, old, min(bytes, hdr->bytes)); + free_hook(old, caller); + + return new; +} + +/** + * Report leaks at library destruction + */ +void __attribute__ ((destructor)) report_leaks() +{ + memory_header_t *hdr; + int leaks = 0; + + for (hdr = first_header.next; hdr != NULL; hdr = hdr->next) + { + printf("Leak (%d bytes at %p)\n", hdr->bytes, hdr + 1); + log_stack_frames(hdr->stack_frames, hdr->stack_frame_count); + leaks++; + } + switch (leaks) + { + case 0: + printf("No leaks detected\n"); + break; + case 1: + printf("One leak detected\n"); + break; + default: + printf("%d leaks detected\n", leaks); + break; + } +} + +/* + * The following glibc functions are excluded from leak detection, since + * they use static allocated buffers or other ugly allocation hacks. + * The Makefile links theses function preferred to their counterparts + * in the target lib... + * TODO: Generic handling would be nice, with a list of blacklisted + * functions. + */ + + +char *inet_ntoa(struct in_addr in) +{ + char *(*_inet_ntoa)(struct in_addr); + void *handle; + char *result; + + pthread_mutex_lock(&mutex); + uninstall_hooks(); + + handle = dlopen("libc.so.6", RTLD_LAZY); + if (handle == NULL) + { + kill(0, SIGSEGV); + } + _inet_ntoa = dlsym(handle, "inet_ntoa"); + + if (_inet_ntoa == NULL) + { + kill(0, SIGSEGV); + } + result = _inet_ntoa(in); + dlclose(handle); + install_hooks(); + pthread_mutex_unlock(&mutex); + return result; +} + + +int pthread_create(pthread_t *__restrict __threadp, __const pthread_attr_t *__restrict __attr, + void *(*__start_routine) (void *), void *__restrict __arg) +{ + int (*_pthread_create) (pthread_t *__restrict __threadp, + __const pthread_attr_t *__restrict __attr, + void *(*__start_routine) (void *), + void *__restrict __arg); + void *handle; + int result; + + pthread_mutex_lock(&mutex); + uninstall_hooks(); + + handle = dlopen("libpthread.so.0", RTLD_LAZY); + if (handle == NULL) + { + kill(0, SIGSEGV); + } + _pthread_create = dlsym(handle, "pthread_create"); + + if (_pthread_create == NULL) + { + kill(0, SIGSEGV); + } + result = _pthread_create(__threadp, __attr, __start_routine, __arg); + dlclose(handle); + install_hooks(); + pthread_mutex_unlock(&mutex); + return result; +} + + +time_t mktime(struct tm *tm) +{ + time_t (*_mktime)(struct tm *tm); + time_t result; + void *handle; + + pthread_mutex_lock(&mutex); + uninstall_hooks(); + + handle = dlopen("libc.so.6", RTLD_LAZY); + if (handle == NULL) + { + kill(0, SIGSEGV); + } + _mktime = dlsym(handle, "mktime"); + + if (_mktime == NULL) + { + kill(0, SIGSEGV); + } + result = _mktime(tm); + dlclose(handle); + install_hooks(); + pthread_mutex_unlock(&mutex); + return result; +} + +#endif /* LEAK_DETECTION */ |