[v2,3/7] malloc: Ensure that the consolidated fast chunk has a sane size.
Commit Message
* malloc/malloc.c (malloc_consolidate): Add size check.
---
malloc/malloc.c | 5 +++++
1 file changed, 5 insertions(+)
Comments
On 11/07/2017 04:27 PM, Istvan Kurucsai wrote:
> * malloc/malloc.c (malloc_consolidate): Add size check.
> ---
> malloc/malloc.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/malloc/malloc.c b/malloc/malloc.c
> index d3fac7e..51d703c 100644
> --- a/malloc/malloc.c
> +++ b/malloc/malloc.c
> @@ -4406,6 +4406,7 @@ static void malloc_consolidate(mstate av)
> mfastbinptr* fb; /* current fastbin being consolidated */
> mfastbinptr* maxfb; /* last fastbin (for loop control) */
> mchunkptr p; /* current chunk being consolidated */
> + unsigned int idx; /* fastbin index of current chunk */
> mchunkptr nextp; /* next chunk to consolidate */
> mchunkptr unsorted_bin; /* bin header */
> mchunkptr first_unsorted; /* chunk to link to */
> @@ -4437,6 +4438,10 @@ static void malloc_consolidate(mstate av)
> p = atomic_exchange_acq (fb, NULL);
> if (p != 0) {
> do {
> + idx = fastbin_index (chunksize (p));
> + if ((&fastbin (av, idx)) != fb)
> + malloc_printerr ("malloc_consolidate(): invalid chunk size");
> +
This looks good. I'm going to minimize the scope for idx and push this.
Thanks,
Florian
@@ -4406,6 +4406,7 @@ static void malloc_consolidate(mstate av)
mfastbinptr* fb; /* current fastbin being consolidated */
mfastbinptr* maxfb; /* last fastbin (for loop control) */
mchunkptr p; /* current chunk being consolidated */
+ unsigned int idx; /* fastbin index of current chunk */
mchunkptr nextp; /* next chunk to consolidate */
mchunkptr unsorted_bin; /* bin header */
mchunkptr first_unsorted; /* chunk to link to */
@@ -4437,6 +4438,10 @@ static void malloc_consolidate(mstate av)
p = atomic_exchange_acq (fb, NULL);
if (p != 0) {
do {
+ idx = fastbin_index (chunksize (p));
+ if ((&fastbin (av, idx)) != fb)
+ malloc_printerr ("malloc_consolidate(): invalid chunk size");
+
check_inuse_chunk(av, p);
nextp = p->fd;