[PATCH 4.17 219/324] drm/tegra: Fix comparison operator for buffer size

From: Greg Kroah-Hartman
Date: Thu Aug 23 2018 - 04:59:47 EST


4.17-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mikko Perttunen <mperttunen@xxxxxxxxxx>

[ 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@xxxxxxxxxx>
Reviewed-by: Dmitry Osipenko <digetx@xxxxxxxxx>
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/tegra/drm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- 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_co
* 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;
}