linux-kernel - [PATCH] drbd: fix memory leak in drbd_adm

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Sun, 26 Apr 2015 01:28:43 -0400
From:	green@...uxhacker.ru
To:	Philipp Reisner <philipp.reisner@...bit.com>,
	Lars Ellenberg <lars.ellenberg@...bit.com>,
	drbd-dev@...ts.linbit.com
Cc:	linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org,
	Oleg Drokin <green@...uxhacker.ru>
Subject: [PATCH] drbd: fix memory leak in drbd_adm_resize

From: Oleg Drokin <green@...uxhacker.ru>

new_disk_conf could be leaked if the follow on checks fail,
so make sure to free it on error if it was not assigned yet.

Found with smatch.

Signed-off-by: Oleg Drokin <green@...uxhacker.ru>
---
I thought about just moving the allocation around so that
there is is no failure path after allocation, but looking
at the history of changes in that file, people tend to insert
extra checks at random places and that's how we ended up
with the current bug, so better let it fail and handle the failure.


 drivers/block/drbd/drbd_nl.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 74df8cf..87fa774 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -2585,6 +2585,7 @@ int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
 		mutex_unlock(&device->resource->conf_update);
 		synchronize_rcu();
 		kfree(old_disk_conf);
+		new_disk_conf = NULL;
 	}
 
 	ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
@@ -2618,6 +2619,7 @@ int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
 
  fail_ldev:
 	put_ldev(device);
+	kfree(new_disk_conf);
 	goto fail;
 }
 
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/