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Diffstat (limited to 'malloc/hooks.c')
-rw-r--r--malloc/hooks.c45
1 files changed, 37 insertions, 8 deletions
diff --git a/malloc/hooks.c b/malloc/hooks.c
index a5c97f3..0f8f274 100644
--- a/malloc/hooks.c
+++ b/malloc/hooks.c
@@ -1,5 +1,5 @@
/* Malloc implementation for multiple threads without lock contention.
- Copyright (C) 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Wolfram Gloger <wg@malloc.de>, 2001.
@@ -146,9 +146,9 @@ mem2mem_check(ptr, sz) Void_t *ptr; size_t sz;
static mchunkptr
internal_function
#if __STD_C
-mem2chunk_check(Void_t* mem)
+mem2chunk_check(Void_t* mem, unsigned char **magic_p)
#else
-mem2chunk_check(mem) Void_t* mem;
+mem2chunk_check(mem, magic_p) Void_t* mem; unsigned char **magic_p;
#endif
{
mchunkptr p;
@@ -173,7 +173,6 @@ mem2chunk_check(mem) Void_t* mem;
for(sz += SIZE_SZ-1; (c = ((unsigned char*)p)[sz]) != magic; sz -= c) {
if(c<=0 || sz<(c+2*SIZE_SZ)) return NULL;
}
- ((unsigned char*)p)[sz] ^= 0xFF;
} else {
unsigned long offset, page_mask = malloc_getpagesize-1;
@@ -193,8 +192,10 @@ mem2chunk_check(mem) Void_t* mem;
for(sz -= 1; (c = ((unsigned char*)p)[sz]) != magic; sz -= c) {
if(c<=0 || sz<(c+2*SIZE_SZ)) return NULL;
}
- ((unsigned char*)p)[sz] ^= 0xFF;
}
+ ((unsigned char*)p)[sz] ^= 0xFF;
+ if (magic_p)
+ *magic_p = (unsigned char *)p + sz;
return p;
}
@@ -232,7 +233,11 @@ top_check()
sbrk_size = front_misalign + mp_.top_pad + MINSIZE;
sbrk_size += pagesz - ((unsigned long)(brk + sbrk_size) & (pagesz - 1));
new_brk = (char*)(MORECORE (sbrk_size));
- if (new_brk == (char*)(MORECORE_FAILURE)) return -1;
+ if (new_brk == (char*)(MORECORE_FAILURE))
+ {
+ MALLOC_FAILURE_ACTION;
+ return -1;
+ }
/* Call the `morecore' hook if necessary. */
if (__after_morecore_hook)
(*__after_morecore_hook) ();
@@ -253,6 +258,11 @@ malloc_check(sz, caller) size_t sz; const Void_t *caller;
{
Void_t *victim;
+ if (sz+1 == 0) {
+ MALLOC_FAILURE_ACTION;
+ return NULL;
+ }
+
(void)mutex_lock(&main_arena.mutex);
victim = (top_check() >= 0) ? _int_malloc(&main_arena, sz+1) : NULL;
(void)mutex_unlock(&main_arena.mutex);
@@ -270,7 +280,7 @@ free_check(mem, caller) Void_t* mem; const Void_t *caller;
if(!mem) return;
(void)mutex_lock(&main_arena.mutex);
- p = mem2chunk_check(mem);
+ p = mem2chunk_check(mem, NULL);
if(!p) {
(void)mutex_unlock(&main_arena.mutex);
@@ -302,10 +312,19 @@ realloc_check(oldmem, bytes, caller)
mchunkptr oldp;
INTERNAL_SIZE_T nb, oldsize;
Void_t* newmem = 0;
+ unsigned char *magic_p;
+ if (bytes+1 == 0) {
+ MALLOC_FAILURE_ACTION;
+ return NULL;
+ }
if (oldmem == 0) return malloc_check(bytes, NULL);
+ if (bytes == 0) {
+ free_check (oldmem, NULL);
+ return NULL;
+ }
(void)mutex_lock(&main_arena.mutex);
- oldp = mem2chunk_check(oldmem);
+ oldp = mem2chunk_check(oldmem, &magic_p);
(void)mutex_unlock(&main_arena.mutex);
if(!oldp) {
malloc_printerr(check_action, "realloc(): invalid pointer", oldmem);
@@ -357,6 +376,12 @@ realloc_check(oldmem, bytes, caller)
#if HAVE_MMAP
}
#endif
+
+ /* mem2chunk_check changed the magic byte in the old chunk.
+ If newmem is NULL, then the old chunk will still be used though,
+ so we need to invert that change here. */
+ if (newmem == NULL) *magic_p ^= 0xFF;
+
(void)mutex_unlock(&main_arena.mutex);
return mem2mem_check(newmem, bytes);
@@ -376,6 +401,10 @@ memalign_check(alignment, bytes, caller)
if (alignment <= MALLOC_ALIGNMENT) return malloc_check(bytes, NULL);
if (alignment < MINSIZE) alignment = MINSIZE;
+ if (bytes+1 == 0) {
+ MALLOC_FAILURE_ACTION;
+ return NULL;
+ }
checked_request2size(bytes+1, nb);
(void)mutex_lock(&main_arena.mutex);
mem = (top_check() >= 0) ? _int_memalign(&main_arena, alignment, bytes+1) :