| Message ID | 1385733756-660-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index b83b40e..ae1b0c4 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -406,6 +406,8 @@ static int dispatch_discard_io(struct xen_blkif *blkif, unsigned long secure; struct phys_req preq; + xen_blkif_get(blkif); + preq.sector_number = req->u.discard.sector_number; preq.nr_sects = req->u.discard.nr_sectors; @@ -418,7 +420,6 @@ static int dispatch_discard_io(struct xen_blkif *blkif, } blkif->st_ds_req++; - xen_blkif_get(blkif); secure = (blkif->vbd.discard_secure && (req->u.discard.flag & BLKIF_DISCARD_SECURE)) ? BLKDEV_DISCARD_SECURE : 0;
This is a note to let you know that I have just added a patch titled xen/blkback: fix reference counting to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From dd8405c7606b911c9505f9fd92d0770c237a3bab Mon Sep 17 00:00:00 2001 From: Vegard Nossum <vegard.nossum@oracle.com> Date: Thu, 5 Sep 2013 13:00:14 +0200 Subject: xen/blkback: fix reference counting commit ea5ec76d76da9279d12027c1828544c5ccbe7932 upstream. If the permission check fails, we drop a reference to the blkif without having taken it in the first place. The bug was introduced in commit 604c499cbbcc3d5fe5fb8d53306aa0fae1990109 (xen/blkback: Check device permissions before allowing OP_DISCARD). Cc: Jan Beulich <JBeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/block/xen-blkback/blkback.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) -- 1.8.3.2