4.9-stable patches

[thirdparty/kernel/stable-queue.git] / releases / 3.16.3 / fix-regression-in-scsi_ioctl_send_command.patch

From 2ba136daa3ae1e881c9f586f283fcaa164767dce Mon Sep 17 00:00:00 2001
From: Tony Battersby <tonyb@cybernetics.com>
Date: Fri, 22 Aug 2014 15:53:35 -0400
Subject: fix regression in SCSI_IOCTL_SEND_COMMAND

From: Tony Battersby <tonyb@cybernetics.com>

commit 2ba136daa3ae1e881c9f586f283fcaa164767dce upstream.

blk_rq_set_block_pc() memsets rq->cmd to 0, so it should come
immediately after blk_get_request() to avoid overwriting the
user-supplied CDB.  Also check for failure to allocate rq.

Fixes: f27b087b81b7 ("block: add blk_rq_set_block_pc()")
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 block/scsi_ioctl.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -438,6 +438,11 @@ int sg_scsi_ioctl(struct request_queue *
 	}
 
 	rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
+	if (!rq) {
+		err = -ENOMEM;
+		goto error;
+	}
+	blk_rq_set_block_pc(rq);
 
 	cmdlen = COMMAND_SIZE(opcode);
 
@@ -491,7 +496,6 @@ int sg_scsi_ioctl(struct request_queue *
 	memset(sense, 0, sizeof(sense));
 	rq->sense = sense;
 	rq->sense_len = 0;
-	blk_rq_set_block_pc(rq);
 
 	blk_execute_rq(q, disk, rq, 0);
 
@@ -511,7 +515,8 @@ out:
 	
 error:
 	kfree(buffer);
-	blk_put_request(rq);
+	if (rq)
+		blk_put_request(rq);
 	return err;
 }
 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);