@@ -126,6 +126,8 @@ static int ide_cmd_ioctl(ide_drive_t *drive, unsigned long arg)
struct request *rq;
rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+ if (!rq)
+ return err;
rq->cmd_type = REQ_TYPE_ATA_TASKFILE;
err = blk_execute_rq(drive->queue, NULL, rq, 0);
blk_put_request(rq);
@@ -222,6 +224,8 @@ static int generic_drive_reset(ide_drive_t *drive)
int ret = 0;
rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
+ if (!rq)
+ return ret;
rq->cmd_type = REQ_TYPE_SPECIAL;
rq->cmd_len = 1;
rq->cmd[0] = REQ_DRIVE_RESET;
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-ioctls.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)