linux-kernel - [PATCH 2/2] [media] v4l2-ctrls: fix integer overflow in try_set_ext

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>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <1333719157-31240-2-git-send-email-xi.wang@gmail.com>
Date:	Fri,  6 Apr 2012 09:32:37 -0400
From:	Xi Wang <xi.wang@...il.com>
To:	Mauro Carvalho Chehab <mchehab@...radead.org>,
	Guennadi Liakhovetski <g.liakhovetski@....de>
Cc:	linux-media@...r.kernel.org, linux-kernel@...r.kernel.org,
	Xi Wang <xi.wang@...il.com>
Subject: [PATCH 2/2] [media] v4l2-ctrls: fix integer overflow in try_set_ext_ctrls()

A large cs->count from userspace may overflow the allocation size,
leading to memory corruption.  try_set_ext_ctrls() can be reached
from subdev_do_ioctl() or __video_do_ioctl().

Use kmalloc_array() to avoid the overflow.

Signed-off-by: Xi Wang <xi.wang@...il.com>
---
 drivers/media/video/v4l2-ctrls.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c
index f355fd5..6f38a5d 100644
--- a/drivers/media/video/v4l2-ctrls.c
+++ b/drivers/media/video/v4l2-ctrls.c
@@ -2219,7 +2219,8 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl,
 		return class_check(hdl, cs->ctrl_class);
 
 	if (cs->count > ARRAY_SIZE(helper)) {
-		helpers = kmalloc(sizeof(helper[0]) * cs->count, GFP_KERNEL);
+		helpers = kmalloc_array(cs->count, sizeof(helper[0]),
+					GFP_KERNEL);
 		if (!helpers)
 			return -ENOMEM;
 	}
-- 
1.7.5.4

--
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/