| Message ID | 1344520529-19164-9-git-send-email-makienko@ispras.ru |
|---|---|
| State | Rejected |
| Delegated to: | David Miller |
| Headers | show |
diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c index ce8237d..c27b05c 100644 --- a/drivers/ide/ide-tape.c +++ b/drivers/ide/ide-tape.c @@ -853,6 +853,8 @@ static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int size) BUG_ON(size < 0 || size % tape->blk_size); rq = blk_get_request(drive->queue, READ, __GFP_WAIT); + if (!rq) + return -EIO; rq->cmd_type = REQ_TYPE_SPECIAL; rq->cmd[13] = cmd; rq->rq_disk = tape->disk;
The function blk_get_request() can return NULL in some cases. There are checks on it if function is called with argumetns one of which is GFP_ATOMIC/GFP_NOIO/etc. If system couldn't find request blk_get_request() return NULL. But if there is function call with argument __GFP_WAIT the system will wait until get request or the queue becomes dead. If something kills the queue, blk_get_request() return NULL and next operations will lead to errors. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Marina Makienko <makienko@ispras.ru> --- drivers/ide/ide-tape.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)