This is a note to let you know that I've just added the patch titled
drm/amdgpu: Fix potential out-of-bounds access in 'amdgpu_discovery_reg_base_init()'
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-amdgpu-fix-potential-out-of-bounds-access-in-amd.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 8892d7bc35057d8873f4538470b12a15c3e96a65
Author: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
Date: Thu Feb 1 22:47:15 2024 +0530
drm/amdgpu: Fix potential out-of-bounds access in 'amdgpu_discovery_reg_base_init()'
[ Upstream commit cdb637d339572398821204a1142d8d615668f1e9 ]
The issue arises when the array 'adev->vcn.vcn_config' is accessed
before checking if the index 'adev->vcn.num_vcn_inst' is within the
bounds of the array.
The fix involves moving the bounds check before the array access. This
ensures that 'adev->vcn.num_vcn_inst' is within the bounds of the array
before it is used as an index.
Fixes the below:
drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1289 amdgpu_discovery_reg_base_init() error: testing array offset 'adev->vcn.num_vcn_inst' after use.
Fixes: a0ccc717c4ab ("drm/amdgpu/discovery: validate VCN and SDMA instances")
Cc: Christian König <christian.koenig@xxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
index 68a901287264f..cf2faeae1d0db 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
@@ -1270,11 +1270,10 @@ static int amdgpu_discovery_reg_base_init(struct amdgpu_device *adev)
* 0b10 : encode is disabled
* 0b01 : decode is disabled
*/
- adev->vcn.vcn_config[adev->vcn.num_vcn_inst] =
- ip->revision & 0xc0;
- ip->revision &= ~0xc0;
if (adev->vcn.num_vcn_inst <
AMDGPU_MAX_VCN_INSTANCES) {
+ adev->vcn.vcn_config[adev->vcn.num_vcn_inst] =
+ ip->revision & 0xc0;
adev->vcn.num_vcn_inst++;
adev->vcn.inst_mask |=
(1U << ip->instance_number);
@@ -1285,6 +1284,7 @@ static int amdgpu_discovery_reg_base_init(struct amdgpu_device *adev)
adev->vcn.num_vcn_inst + 1,
AMDGPU_MAX_VCN_INSTANCES);
}
+ ip->revision &= ~0xc0;
}
if (le16_to_cpu(ip->hw_id) == SDMA0_HWID ||
le16_to_cpu(ip->hw_id) == SDMA1_HWID ||
