| Message ID | 1344520529-19164-7-git-send-email-makienko@ispras.ru |
|---|---|
| State | Rejected |
| Delegated to: | David Miller |
| Headers | show |
diff --git a/drivers/ide/ide-disk.c b/drivers/ide/ide-disk.c index 16f69be..538d206 100644 --- a/drivers/ide/ide-disk.c +++ b/drivers/ide/ide-disk.c @@ -479,6 +479,10 @@ static int set_multcount(ide_drive_t *drive, int arg) return -EBUSY; rq = blk_get_request(drive->queue, READ, __GFP_WAIT); + if (!rq) { + printk(KERN_ERR PFX"set_multcount: blk_get_request() failed. \n"); + return 1; + } rq->cmd_type = REQ_TYPE_ATA_TASKFILE; drive->mult_req = arg;
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-disk.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)