diff options
Diffstat (limited to 'malloc/malloc.c')
| -rw-r--r-- | malloc/malloc.c | 24 |
1 files changed, 15 insertions, 9 deletions
diff --git a/malloc/malloc.c b/malloc/malloc.c index ba32992999..2cf2025237 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -1772,15 +1772,15 @@ __malloc_check_init() static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */ -#define MMAP(size, prot, flags) ((dev_zero_fd < 0) ? \ +#define MMAP(addr, size, prot, flags) ((dev_zero_fd < 0) ? \ (dev_zero_fd = open("/dev/zero", O_RDWR), \ - mmap(0, (size), (prot), (flags), dev_zero_fd, 0)) : \ - mmap(0, (size), (prot), (flags), dev_zero_fd, 0)) + mmap((addr), (size), (prot), (flags), dev_zero_fd, 0)) : \ + mmap((addr), (size), (prot), (flags), dev_zero_fd, 0)) #else -#define MMAP(size, prot, flags) \ - (mmap(0, (size), (prot), (flags)|MAP_ANONYMOUS, -1, 0)) +#define MMAP(addr, size, prot, flags) \ + (mmap((addr), (size), (prot), (flags)|MAP_ANONYMOUS, -1, 0)) #endif @@ -1806,7 +1806,7 @@ mmap_chunk(size) size_t size; */ size = (size + SIZE_SZ + page_mask) & ~page_mask; - p = (mchunkptr)MMAP(size, PROT_READ|PROT_WRITE, MAP_PRIVATE); + p = (mchunkptr)MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE); if(p == (mchunkptr) MAP_FAILED) return 0; n_mmaps++; @@ -1939,7 +1939,7 @@ new_heap(size) size_t size; No swap space needs to be reserved for the following large mapping (on Linux, this is the case for all non-writable mappings anyway). */ - p1 = (char *)MMAP(HEAP_MAX_SIZE<<1, PROT_NONE, MAP_PRIVATE|MAP_NORESERVE); + p1 = (char *)MMAP(0, HEAP_MAX_SIZE<<1, PROT_NONE, MAP_PRIVATE|MAP_NORESERVE); if(p1 == MAP_FAILED) return 0; p2 = (char *)(((unsigned long)p1 + HEAP_MAX_SIZE) & ~(HEAP_MAX_SIZE-1)); @@ -1980,7 +1980,10 @@ grow_heap(h, diff) heap_info *h; long diff; new_size = (long)h->size + diff; if(new_size < (long)sizeof(*h)) return -1; - if(mprotect((char *)h + new_size, -diff, PROT_NONE) != 0) + /* Try to re-map the extra heap space freshly to save memory, and + make it inaccessible. */ + if((char *)MMAP((char *)h + new_size, -diff, PROT_NONE, + MAP_PRIVATE|MAP_FIXED) == (char *) MAP_FAILED) return -2; } h->size = new_size; @@ -2136,7 +2139,10 @@ static void do_check_chunk(ar_ptr, p) arena *ar_ptr; mchunkptr p; if(ar_ptr != &main_arena) { heap_info *heap = heap_for_ptr(p); assert(heap->ar_ptr == ar_ptr); - assert((char *)p + sz <= (char *)heap + heap->size); + if(p != top(ar_ptr)) + assert((char *)p + sz <= (char *)heap + heap->size); + else + assert((char *)p + sz == (char *)heap + heap->size); return; } #endif |