[SCSI] BUG_ON() impossible condition in sg list counting
If blk_rq_map_sg wrote more than was allocated in the scatterlist,
BUG_ON() is probably the right thing to do.
[jejb: rejections fixed up]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c
index 241815e..93ece8f 100644
--- a/drivers/scsi/scsi_tgt_lib.c
+++ b/drivers/scsi/scsi_tgt_lib.c
@@ -368,14 +368,9 @@
dprintk("cmd %p cnt %d %lu\n", cmd, scsi_sg_count(cmd),
rq_data_dir(rq));
count = blk_rq_map_sg(rq->q, rq, scsi_sglist(cmd));
- if (likely(count <= scsi_sg_count(cmd))) {
- cmd->use_sg = count;
- return 0;
- }
-
- eprintk("cmd %p cnt %d\n", cmd, scsi_sg_count(cmd));
- scsi_free_sgtable(cmd);
- return -EINVAL;
+ BUG_ON(count > cmd->use_sg);
+ cmd->use_sg = count;
+ return 0;
}
/* TODO: test this crap and replace bio_map_user with new interface maybe */