Description
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: fix division by zero in get_estimated_bw() get_estimated_bw() divides by link->dpia_bw_alloc_config.bw_granularity, which is zeroed by reset_bw_alloc_struct() and only populated once DP_TUNNELING_BW_ALLOC_CAP_CHANGED has been handled. link_dp_dpia_handle_bw_alloc_status(), the DPCD interrupt handler, calls get_estimated_bw() whenever DP_TUNNELING_ESTIMATED_BW_CHANGED is set, independently of whether DP_TUNNELING_BW_ALLOC_CAP_CHANGED has ever fired for that link. A connected USB4/DPIA tunneling device that reports an estimated-bandwidth change before ever reporting a capability change drives a division by zero in this IRQ path. link_dpia_send_bw_alloc_request() already guards the same bw_granularity division; add the identical guard here rather than introducing a new pattern. (cherry picked from commit f2a961457c33dc34223aad5c9e8971de34a4eed3)
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
8e5cfe547bf3beeb29d9608be68d22dff2b5012b to < 4c5b61b9df6ab33b55f228e1b6579cefad11a9f7affected8e5cfe547bf3beeb29d9608be68d22dff2b5012b to < ac2ab58a79bf2401ae8c5d1c030bf0a5a376f43aaffected8e5cfe547bf3beeb29d9608be68d22dff2b5012b to < 4814f28c45f58a71a80d09b80a60da6a063b539aaffected8e5cfe547bf3beeb29d9608be68d22dff2b5012b to < b08c3d5ee7feadd821208f7c2c1ec02a16ce5878affected8e5cfe547bf3beeb29d9608be68d22dff2b5012b to < f63de9054da858d57054474c32464106f8375e0daffected
Linux Linux
Default version status: affected
6.3affected0 to < 6.3unaffected6.6.157 to ≤ 6.6.*unaffected6.12.110 to ≤ 6.12.*unaffected6.18.51 to ≤ 6.18.*unaffected7.2.5 to ≤ 7.2.*unaffected7.3 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/4c5b61b9df6ab33b55f228e1b6579cefad11a9f7 ↗
- https://git.kernel.org/stable/c/ac2ab58a79bf2401ae8c5d1c030bf0a5a376f43a ↗
- https://git.kernel.org/stable/c/4814f28c45f58a71a80d09b80a60da6a063b539a ↗
- https://git.kernel.org/stable/c/b08c3d5ee7feadd821208f7c2c1ec02a16ce5878 ↗
- https://git.kernel.org/stable/c/f63de9054da858d57054474c32464106f8375e0d ↗