lkml.org 
[lkml]   [2009]   [Oct]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH -repost 4/4] SCSI: scsi_lib, fix potential NULL dereference
Date
Stanse found a potential NULL dereference in scsi_kill_request.

Instead of triggering BUG() in 'if (unlikely(cmd == NULL))' branch,
the kernel will Oops earlier on cmd dereference.

Move the dereferences after the if.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: James E.J. Bottomley <James.Bottomley@suse.de>
---
drivers/scsi/scsi_lib.c | 9 ++++++---
1 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 39b5858..53bdd25 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1359,9 +1359,9 @@ static int scsi_lld_busy(struct request_queue *q)
static void scsi_kill_request(struct request *req, struct request_queue *q)
{
struct scsi_cmnd *cmd = req->special;
- struct scsi_device *sdev = cmd->device;
- struct scsi_target *starget = scsi_target(sdev);
- struct Scsi_Host *shost = sdev->host;
+ struct scsi_device *sdev;
+ struct scsi_target *starget;
+ struct Scsi_Host *shost;

blk_start_request(req);

@@ -1371,6 +1371,9 @@ static void scsi_kill_request(struct request *req, struct request_queue *q)
BUG();
}

+ sdev = cmd->device;
+ starget = scsi_target(sdev);
+ shost = sdev->host;
scsi_init_cmd_errh(cmd);
cmd->result = DID_NO_CONNECT << 16;
atomic_inc(&cmd->device->iorequest_cnt);
--
1.6.4.2


\
 
 \ /
  Last update: 2009-10-09 16:03    [W:0.034 / U:0.164 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site