Commit 91724c20 authored Jan 15, 2015 by Ewan D. Milne Committed by Christoph Hellwig Jan 20, 2015

scsi: Avoid crashing if device uses DIX but adapter does not support it



This can happen if a multipathed device uses DIX and another path is
added via an adapter that does not support it.  Multipath should not
allow this path to be added, but we should not depend upon that to avoid
crashing.

Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

parent 99531e60

drivers/scsi/scsi_lib.c

+11 −1

Original line number	Diff line number	Diff line
		@@ -1143,7 +1143,17 @@ int scsi_init_io(struct scsi_cmnd *cmd)
		struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
		int ivecs, count;

		BUG_ON(prot_sdb == NULL);
		if (prot_sdb == NULL) {
		/*
		* This can happen if someone (e.g. multipath)
		* queues a command to a device on an adapter
		* that does not support DIX.
		*/
		WARN_ON_ONCE(1);
		error = BLKPREP_KILL;
		goto err_exit;
		}

		ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio);

		if (scsi_alloc_sgtable(prot_sdb, ivecs, is_mq)) {