diff options
| author | Munehisa Kamata <kamatam@amazon.com> | 2017-08-10 01:31:40 +0300 |
|---|---|---|
| committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2017-08-15 17:34:04 +0300 |
| commit | b15bd8cb37598afb2963f7eb9e2de468d2d60a2f (patch) | |
| tree | 7c81882b72db9488b87fd9c516512b6499ad4210 | |
| parent | 462cdace790ac2ed6aad1b19c9c0af0143b6aab0 (diff) | |
| download | linux-b15bd8cb37598afb2963f7eb9e2de468d2d60a2f.tar.xz | |
xen-blkfront: use a right index when checking requests
Since commit d05d7f40791c ("Merge branch 'for-4.8/core' of
git://git.kernel.dk/linux-block") and 3fc9d690936f ("Merge branch
'for-4.8/drivers' of git://git.kernel.dk/linux-block"), blkfront_resume()
has been using an index for iterating ring_info to check request when
iterating blk_shadow in an inner loop. This seems to have been
accidentally introduced during the massive rewrite of the block layer
macros in the commits.
This may cause crash like this:
[11798.057074] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[11798.058832] IP: [<ffffffff814411fa>] blkfront_resume+0x10a/0x610
....
[11798.061063] Call Trace:
[11798.061063] [<ffffffff8139ce93>] xenbus_dev_resume+0x53/0x140
[11798.061063] [<ffffffff8139ce40>] ? xenbus_dev_probe+0x150/0x150
[11798.061063] [<ffffffff813f359e>] dpm_run_callback+0x3e/0x110
[11798.061063] [<ffffffff813f3a08>] device_resume+0x88/0x190
[11798.061063] [<ffffffff813f4cc0>] dpm_resume+0x100/0x2d0
[11798.061063] [<ffffffff813f5221>] dpm_resume_end+0x11/0x20
[11798.061063] [<ffffffff813950a8>] do_suspend+0xe8/0x1a0
[11798.061063] [<ffffffff813954bd>] shutdown_handler+0xfd/0x130
[11798.061063] [<ffffffff8139aba0>] ? split+0x110/0x110
[11798.061063] [<ffffffff8139ac26>] xenwatch_thread+0x86/0x120
[11798.061063] [<ffffffff810b4570>] ? prepare_to_wait_event+0x110/0x110
[11798.061063] [<ffffffff8108fe57>] kthread+0xd7/0xf0
[11798.061063] [<ffffffff811da811>] ? kfree+0x121/0x170
[11798.061063] [<ffffffff8108fd80>] ? kthread_park+0x60/0x60
[11798.061063] [<ffffffff810863b0>] ? call_usermodehelper_exec_work+0xb0/0xb0
[11798.061063] [<ffffffff810864ea>] ? call_usermodehelper_exec_async+0x13a/0x140
[11798.061063] [<ffffffff81534a45>] ret_from_fork+0x25/0x30
Use the right index in the inner loop.
Fixes: d05d7f40791c ("Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-block")
Fixes: 3fc9d690936f ("Merge branch 'for-4.8/drivers' of git://git.kernel.dk/linux-block")
Signed-off-by: Munehisa Kamata <kamatam@amazon.com>
Reviewed-by: Thomas Friebel <friebelt@amazon.de>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Roger Pau Monne <roger.pau@citrix.com>
Cc: xen-devel@lists.xenproject.org
Cc: stable@vger.kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| -rw-r--r-- | drivers/block/xen-blkfront.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 98e34e4c62b8..2468c28d4771 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -2075,9 +2075,9 @@ static int blkfront_resume(struct xenbus_device *dev) /* * Get the bios in the request so we can re-queue them. */ - if (req_op(shadow[i].request) == REQ_OP_FLUSH || - req_op(shadow[i].request) == REQ_OP_DISCARD || - req_op(shadow[i].request) == REQ_OP_SECURE_ERASE || + if (req_op(shadow[j].request) == REQ_OP_FLUSH || + req_op(shadow[j].request) == REQ_OP_DISCARD || + req_op(shadow[j].request) == REQ_OP_SECURE_ERASE || shadow[j].request->cmd_flags & REQ_FUA) { /* * Flush operations don't contain bios, so |