From: Mikko Perttunen <mperttunen@nvidia.com>
Date: Wed, 20 Jun 2018 13:03:58 +0000 (+0300)
Subject: drm/tegra: Fix comparison operator for buffer size
X-Git-Tag: v4.17.19~106
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0c5a08372faf7b587eb952ad697e7bd9d7480448;p=thirdparty%2Fkernel%2Fstable.git

drm/tegra: Fix comparison operator for buffer size

[ Upstream commit 5265f0338bc0feec6c0d544dfe005dec1a93cb93 ]

Here we are checking for the buffer length, not an offset for writing
to, so using > is correct. The current code incorrectly rejects a
command buffer ending at the memory buffer's end.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index 7afe2f635f741..500b7c5b66729 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -436,7 +436,7 @@ int tegra_drm_submit(struct tegra_drm_context *context,
 		 * unaligned offset is malformed and cause commands stream
 		 * corruption on the buffer address relocation.
 		 */
-		if (offset & 3 || offset >= obj->gem.size) {
+		if (offset & 3 || offset > obj->gem.size) {
 			err = -EINVAL;
 			goto fail;
 		}