diff options
Diffstat (limited to 'malloc/malloc.c')
| -rw-r--r-- | malloc/malloc.c | 30 |
1 files changed, 22 insertions, 8 deletions
diff --git a/malloc/malloc.c b/malloc/malloc.c index f5aafd2..7889fb1 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -1224,14 +1224,21 @@ nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ MINSIZE : \ ((req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK) -/* Same, except also perform argument check */ - -#define checked_request2size(req, sz) \ - if (REQUEST_OUT_OF_RANGE (req)) { \ - __set_errno (ENOMEM); \ - return 0; \ - } \ - (sz) = request2size (req); +/* Same, except also perform an argument and result check. First, we check + that the padding done by request2size didn't result in an integer + overflow. Then we check (using REQUEST_OUT_OF_RANGE) that the resulting + size isn't so large that a later alignment would lead to another integer + overflow. */ +#define checked_request2size(req, sz) \ +({ \ + (sz) = request2size (req); \ + if (((sz) < (req)) \ + || REQUEST_OUT_OF_RANGE (sz)) \ + { \ + __set_errno (ENOMEM); \ + return 0; \ + } \ +}) /* --------------- Physical chunk operations --------------- @@ -4678,6 +4685,13 @@ _int_memalign (mstate av, size_t alignment, size_t bytes) */ + /* Check for overflow. */ + if (nb > SIZE_MAX - alignment - MINSIZE) + { + __set_errno (ENOMEM); + return 0; + } + /* Call malloc with worst case padding to hit alignment. */ m = (char *) (_int_malloc (av, nb + alignment + MINSIZE)); |