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 6.7-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-6.7 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 28547f2c1c30e376ec0f225710db67548ec516a8 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 c7d60dd0fb975..4f9900779ef9e 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c @@ -1278,11 +1278,10 @@ 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); @@ -1293,6 +1292,7 @@ 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 ||