[PATCH AUTOSEL 5.15 07/20] drm: vmwgfx_surface.c: copy user-array safely

[Sasha Levin]

From: Philipp Stanner <pstanner@xxxxxxxxxx>

[ Upstream commit 06ab64a0d836ac430c5f94669710a78aa43942cb ]

Currently, there is no overflow-check with memdup_user().

Use the new function memdup_array_user() instead of memdup_user() for
duplicating the user-space array safely.

Suggested-by: David Airlie <airlied@xxxxxxxxxx>
Signed-off-by: Philipp Stanner <pstanner@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Zack Rusin <zackr@xxxxxxxxxx>
Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20230920123612.16914-7-pstanner@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
index 5d53a5f9d1237..872af7d4b3fc9 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
@@ -807,9 +807,9 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data,
 	metadata->num_sizes = num_sizes;
 	user_srf->size = size;
 	metadata->sizes =
-		memdup_user((struct drm_vmw_size __user *)(unsigned long)
+		memdup_array_user((struct drm_vmw_size __user *)(unsigned long)
 			    req->size_addr,
-			    sizeof(*metadata->sizes) * metadata->num_sizes);
+			    metadata->num_sizes, sizeof(*metadata->sizes));
 	if (IS_ERR(metadata->sizes)) {
 		ret = PTR_ERR(metadata->sizes);
 		goto out_no_sizes;
-- 
2.42.0