From: Guchun Chen <guchun.chen@amd.com>
Date: Tue, 30 Mar 2021 14:02:06 +0000 (+0800)
Subject: drm/radeon: avoid potential null pointer access
X-Git-Tag: v5.13-rc1~123^2~3^2~62
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fd6ecc906960c1063c17f23b0b8dad5f6dcea4bc;p=thirdparty%2Fkernel%2Flinux.git

drm/radeon: avoid potential null pointer access

Leverage the same logic from amdgpu_ttm_tt_unpin_userptr.

Signed-off-by: Guchun Chen <guchun.chen@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
index c84e128daff87..cdb6d3efd07db 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -415,7 +415,7 @@ static void radeon_ttm_tt_unpin_userptr(struct ttm_device *bdev, struct ttm_tt *
 		DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
 
 	/* double check that we don't free the table twice */
-	if (!ttm->sg->sgl)
+	if (!ttm->sg || !ttm->sg->sgl)
 		return;
 
 	/* free the sg table and pages again */