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@xxxxxxxxx> --- drivers/ide/ide-devsets.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/drivers/ide/ide-devsets.c b/drivers/ide/ide-devsets.c index 9e98122..acdb87f 100644 --- a/drivers/ide/ide-devsets.c +++ b/drivers/ide/ide-devsets.c @@ -166,6 +166,8 @@ int ide_devset_execute(ide_drive_t *drive, const struct ide_devset *setting, return setting->set(drive, arg); rq = blk_get_request(q, READ, __GFP_WAIT); + if (!rq) + return -EIO; rq->cmd_type = REQ_TYPE_SPECIAL; rq->cmd_len = 5; rq->cmd[0] = REQ_DEVSET_EXEC; -- 1.7.7 -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
