From e3fd2bfb35763fca751e94b0ddb42c2303177bbc Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Fri, 28 Feb 2020 12:23:21 +0300
Subject: drm: prevent a harmless integer overflow in drm_legacy_sg_alloc()
Git-commit: abdd768e9ce18142c376188bfca4357ba489afb3
Patch-mainline: v5.7-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
There is an integer overflow when we round up to PAGE_SIZE, but it's
harmless because we never re-use "request->size" for anything meaningful.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200228092321.axulddmkxrujkmas@kili.mountain
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/drm_scatter.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/drm_scatter.c b/drivers/gpu/drm/drm_scatter.c
index d5c386154246..ca520028b2cb 100644
--- a/drivers/gpu/drm/drm_scatter.c
+++ b/drivers/gpu/drm/drm_scatter.c
@@ -99,6 +99,9 @@ int drm_legacy_sg_alloc(struct drm_device *dev, void *data,
if (!drm_core_check_feature(dev, DRIVER_SG))
return -EOPNOTSUPP;
+ if (request->size > SIZE_MAX - PAGE_SIZE)
+ return -EINVAL;
+
if (dev->sg)
return -EINVAL;
--
2.28.0