On 03/03/2016 10:43, Gonglei wrote:
> CID 1352418 (#1 of 1): Out-of-bounds access (INCOMPATIBLE_CAST)
> incompatible_cast: Pointer &snap_id points to an object whose effective
> type is unsigned int (32 bits, unsigned) but is dereferenced as a wider
> unsigned long (64 bits, unsigned). This may lead to memory corruption.
>
> We also need to free local_err when ret is not equals to 0.
>
> Signed-off-by: Gonglei <arei.gong...@huawei.com>
> ---
> block/sheepdog.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/block/sheepdog.c b/block/sheepdog.c
> index 8739acc..3d81bba 100644
> --- a/block/sheepdog.c
> +++ b/block/sheepdog.c
> @@ -2543,7 +2543,7 @@ static int sd_snapshot_delete(BlockDriverState *bs,
> const char *name,
> Error **errp)
> {
> - uint32_t snap_id = 0;
> + unsigned long snap_id = 0;
> char snap_tag[SD_MAX_VDI_TAG_LEN];
> Error *local_err = NULL;
> int fd, ret;
> @@ -2565,20 +2565,23 @@ static int sd_snapshot_delete(BlockDriverState *bs,
> memset(buf, 0, sizeof(buf));
> memset(snap_tag, 0, sizeof(snap_tag));
> pstrcpy(buf, SD_MAX_VDI_LEN, s->name);
> - if (qemu_strtoul(snapshot_id, NULL, 10, (unsigned long *)&snap_id)) {
> + if (qemu_strtoul(snapshot_id, NULL, 10, &snap_id)) {
> return -1;
> }
>
> if (snap_id) {
> + assert(snap_id <= UINT_MAX);
> +
> hdr.snapid = snap_id;
> } else {
> pstrcpy(snap_tag, sizeof(snap_tag), snapshot_id);
> pstrcpy(buf + SD_MAX_VDI_LEN, SD_MAX_VDI_TAG_LEN, snap_tag);
> }
>
> - ret = find_vdi_name(s, s->name, snap_id, snap_tag, &vid, true,
> + ret = find_vdi_name(s, s->name, hdr.snapid, snap_tag, &vid, true,
> &local_err);
> if (ret) {
> + error_report_err(local_err);
> return ret;
> }
>
>
A patch for this has been posted yesterday by Jeff Cody.
Paolo
