diff options
Diffstat (limited to 'malloc')
| -rw-r--r-- | malloc/malloc.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/malloc/malloc.c b/malloc/malloc.c index b62ffb5..cf1b935 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -3434,6 +3434,17 @@ public_rEALLOc(Void_t* oldmem, size_t bytes) oldp = mem2chunk(oldmem); oldsize = chunksize(oldp); + /* Little security check which won't hurt performance: the + allocator never wrapps around at the end of the address space. + Therefore we can exclude some size values which might appear + here by accident or by "design" from some intruder. */ + if (__builtin_expect ((uintptr_t) oldp > (uintptr_t) -oldsize, 0) + || __builtin_expect ((uintptr_t) oldp & MALLOC_ALIGN_MASK, 0)) + { + malloc_printerr (check_action, "realloc(): invalid pointer", oldmem); + return NULL; + } + checked_request2size(bytes, nb); #if HAVE_MMAP @@ -4205,7 +4216,6 @@ _int_free(mstate av, Void_t* mem) mchunkptr bck; /* misc temp for linking */ mchunkptr fwd; /* misc temp for linking */ - const char *errstr = NULL; p = mem2chunk(mem); @@ -4215,7 +4225,8 @@ _int_free(mstate av, Void_t* mem) allocator never wrapps around at the end of the address space. Therefore we can exclude some size values which might appear here by accident or by "design" from some intruder. */ - if (__builtin_expect ((uintptr_t) p > (uintptr_t) -size, 0)) + if (__builtin_expect ((uintptr_t) p > (uintptr_t) -size, 0) + || __builtin_expect ((uintptr_t) p & MALLOC_ALIGN_MASK, 0)) { errstr = "free(): invalid pointer"; errout: |