linux-kernel - [PATCH v2 2/2] drm/i915: fix integer overflow in i915_gem_do

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] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 23 Apr 2012 04:06:42 -0400
From:	Xi Wang <xi.wang@...il.com>
To:	Daniel Vetter <daniel.vetter@...ll.ch>,
	Keith Packard <keithp@...thp.com>
Cc:	intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
	linux-kernel@...r.kernel.org, security@...nel.org,
	Xi Wang <xi.wang@...il.com>,
	Chris Wilson <chris@...is-wilson.co.uk>, stable@...r.kernel.org
Subject: [PATCH v2 2/2] drm/i915: fix integer overflow in i915_gem_do_execbuffer()

On 32-bit systems, a large args->num_cliprects from userspace via ioctl
may overflow the allocation size, leading to out-of-bounds access.

This vulnerability was introduced in commit 432e58ed ("drm/i915: Avoid
allocation for execbuffer object list").

Signed-off-by: Xi Wang <xi.wang@...il.com>
Cc: Chris Wilson <chris@...is-wilson.co.uk>
Cc: stable@...r.kernel.org
---
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 7c50e58..de43194 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1133,6 +1133,11 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
 			return -EINVAL;
 		}
 
+		if (args->num_cliprects > UINT_MAX / sizeof(*cliprects)) {
+			DRM_DEBUG("execbuf with %u cliprects\n",
+				  args->num_cliprects);
+			return -EINVAL;
+		}
 		cliprects = kmalloc(args->num_cliprects * sizeof(*cliprects),
 				    GFP_KERNEL);
 		if (cliprects == NULL) {
-- 
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/