We were checking for iter to be NULL after dereferencing it. Lets first
check it and then use it.
Signed-off-by: Sudip Mukherjee <[email protected]>
---
block/blk-map.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/block/blk-map.c b/block/blk-map.c
index a54f054..089ed59 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -126,7 +126,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
const struct iov_iter *iter, gfp_t gfp_mask)
{
struct iovec iov, prv = {.iov_base = NULL, .iov_len = 0};
- bool copy = (q->dma_pad_mask & iter->count) || map_data;
+ bool copy;
struct bio *bio = NULL;
struct iov_iter i;
int ret;
@@ -134,6 +134,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
if (!iter || !iter->count)
return -EINVAL;
+ copy = (q->dma_pad_mask & iter->count) || map_data;
iov_for_each(iov, i, *iter) {
unsigned long uaddr = (unsigned long) iov.iov_base;
--
1.9.1
On Thu, Mar 10, 2016 at 05:09:13PM +0530, Sudip Mukherjee wrote:
> We were checking for iter to be NULL after dereferencing it. Lets first
> check it and then use it.
>
> Signed-off-by: Sudip Mukherjee <[email protected]>
Good catch
Reviewed-by: Johannes Thumshirn <[email protected]>
--
Johannes Thumshirn Storage
[email protected] +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: Felix Imend?rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N?rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850
On 03/10/2016 04:39 AM, Sudip Mukherjee wrote:
> We were checking for iter to be NULL after dereferencing it. Lets first
> check it and then use it.
Nobody calls it with iter == NULL, I think we should just kill the !iter
check
--
Jens Axboe