[PATCH AUTOSEL 4.19 01/21] drm/radeon/r600_cs: Fix possible int overflow in r600_packet3_check()

[Sasha Levin <sashal@kernel.org>]

From: Igor Artemiev <Igor.A.Artemiev@mcst.ru>

[ Upstream commit a1e2da6a5072f8abe5b0feaa91a5bcd9dc544a04 ]

It is possible, although unlikely, that an integer overflow will occur
when the result of radeon_get_ib_value() is shifted to the left.

Avoid it by casting one of the operands to larger data type (u64).

Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.

Signed-off-by: Igor Artemiev <Igor.A.Artemiev@mcst.ru>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/radeon/r600_cs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/radeon/r600_cs.c b/drivers/gpu/drm/radeon/r600_cs.c
index b6bdfb3f4a7f7..580ca4f753531 100644
--- a/drivers/gpu/drm/radeon/r600_cs.c
+++ b/drivers/gpu/drm/radeon/r600_cs.c
@@ -2104,7 +2104,7 @@ static int r600_packet3_check(struct radeon_cs_parser *p,
 				return -EINVAL;
 			}
 
-			offset = radeon_get_ib_value(p, idx+1) << 8;
+			offset = (u64)radeon_get_ib_value(p, idx+1) << 8;
 			if (offset != track->vgt_strmout_bo_offset[idx_value]) {
 				DRM_ERROR("bad STRMOUT_BASE_UPDATE, bo offset does not match: 0x%llx, 0x%x\n",
 					  offset, track->vgt_strmout_bo_offset[idx_value]);
-- 
2.43.0