linux-scsi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Tony Battersby <tonyb@cybernetics.com>
To: linux-scsi@vger.kernel.org,
	"James E.J. Bottomley" <JBottomley@parallels.com>,
	Christoph Hellwig <hch@infradead.org>,
	Jens Axboe <axboe@kernel.dk>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH] blk-mq: fix double-free in error path
Date: Wed, 11 Feb 2015 11:32:30 -0500	[thread overview]
Message-ID: <54DB841E.6030108@cybernetics.com> (raw)

If the allocation of bt->bs fails, then bt->map can be freed twice, once
in blk_mq_init_bitmap_tags() -> bt_alloc(), and once in
blk_mq_init_bitmap_tags() -> bt_free().  Fix by setting the pointer to
NULL after the first free.

Cc: <stable@vger.kernel.org>
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
---

For inclusion in kernel 3.20.

--- linux-3.19.0/block/blk-mq-tag.c.orig	2015-02-08 21:54:22.000000000 -0500
+++ linux-3.19.0/block/blk-mq-tag.c	2015-02-10 09:42:38.000000000 -0500
@@ -509,6 +509,7 @@ static int bt_alloc(struct blk_mq_bitmap
 	bt->bs = kzalloc(BT_WAIT_QUEUES * sizeof(*bt->bs), GFP_KERNEL);
 	if (!bt->bs) {
 		kfree(bt->map);
+		bt->map = NULL;
 		return -ENOMEM;
 	}
 


             reply	other threads:[~2015-02-11 16:32 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-02-11 16:32 Tony Battersby [this message]
2015-02-11 16:43 ` [PATCH] blk-mq: fix double-free in error path Jens Axboe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=54DB841E.6030108@cybernetics.com \
    --to=tonyb@cybernetics.com \
    --cc=JBottomley@parallels.com \
    --cc=axboe@kernel.dk \
    --cc=hch@infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).