6.11-stable review patch. If anyone has any objections, please let me know.
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From: Rodrigo Siqueira Rodrigo.Siqueira@amd.com
commit 16dd2825c23530f2259fc671960a3a65d2af69bd upstream.
At some point, the IEEE ID identification for the replay check in the AMD EDID was added. However, this check causes the following out-of-bounds issues when using KASAN:
[ 27.804016] BUG: KASAN: slab-out-of-bounds in amdgpu_dm_update_freesync_caps+0xefa/0x17a0 [amdgpu] [ 27.804788] Read of size 1 at addr ffff8881647fdb00 by task systemd-udevd/383
...
[ 27.821207] Memory state around the buggy address: [ 27.821215] ffff8881647fda00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.821224] ffff8881647fda80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.821234] >ffff8881647fdb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.821243] ^ [ 27.821250] ffff8881647fdb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.821259] ffff8881647fdc00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.821268] ==================================================================
This is caused because the ID extraction happens outside of the range of the edid lenght. This commit addresses this issue by considering the amd_vsdb_block size.
Cc: ChiaHsuan Chung chiahsuan.chung@amd.com Reviewed-by: Leo Li sunpeng.li@amd.com Signed-off-by: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Signed-off-by: Hamza Mahfooz hamza.mahfooz@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com (cherry picked from commit b7e381b1ccd5e778e3d9c44c669ad38439a861d8) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -12038,7 +12038,7 @@ static int parse_amd_vsdb(struct amdgpu_ break; }
- while (j < EDID_LENGTH) { + while (j < EDID_LENGTH - sizeof(struct amd_vsdb_block)) { struct amd_vsdb_block *amd_vsdb = (struct amd_vsdb_block *)&edid_ext[j]; unsigned int ieeeId = (amd_vsdb->ieee_id[2] << 16) | (amd_vsdb->ieee_id[1] << 8) | (amd_vsdb->ieee_id[0]);