Commit 49c67980 authored Apr 09, 2019 by Jaesoo Lee Committed by Greg Kroah-Hartman Apr 27, 2019

scsi: core: set result when the command cannot be dispatched



commit be549d49115422f846b6d96ee8fd7173a5f7ceb0 upstream.

When SCSI blk-mq is enabled, there is a bug in handling errors in
scsi_queue_rq.  Specifically, the bug is not setting result field of
scsi_request correctly when the dispatch of the command has been
failed. Since the upper layer code including the sg_io ioctl expects to
receive any error status from result field of scsi_request, the error is
silently ignored and this could cause data corruptions for some
applications.

Fixes: d285203c ("scsi: add support for a blk-mq based I/O path.")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jaesoo Lee <jalee@purestorage.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent d11a33e9

drivers/scsi/scsi_lib.c

+5 −1

Original line number	Original line	Diff line number	Diff line
	@@ -2050,8 +2050,12 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
	blk_mq_delay_run_hw_queue(hctx, SCSI_QUEUE_DELAY);		blk_mq_delay_run_hw_queue(hctx, SCSI_QUEUE_DELAY);
	break;		break;
	default:		default:
			if (unlikely(!scsi_device_online(sdev)))
			scsi_req(req)->result = DID_NO_CONNECT << 16;
			else
			scsi_req(req)->result = DID_ERROR << 16;
	/*		/*
	* Make sure to release all allocated ressources when		* Make sure to release all allocated resources when
	* we hit an error, as we will never see this command		* we hit an error, as we will never see this command
	* again.		* again.
	*/		*/