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authorMartin Willi <martin@strongswan.org>2006-04-10 08:07:38 +0000
committerMartin Willi <martin@strongswan.org>2006-04-10 08:07:38 +0000
commit5113680f95e522c677cdd37072cfffbdca06831e (patch)
tree973ac57accbc66b042e5307942c6cbbbf4f19579 /Source/lib/utils/leak_detective.c
parent6862128151fb78f63685a8da5575783c426d64a7 (diff)
downloadstrongswan-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.c382
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
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+++ 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 */