[PATCH ath-next 1/2] wifi: ath12k: fix dp_link_peer dangling references on AP vdev rollback

[Rameshkumar Sundaram]

On 6/17/2026 2:58 PM, Baochen Qiang wrote:
> ath12k_mac_vdev_create() for an AP vdev creates the bss self-peer via
> ath12k_peer_create(), which finishes by calling
> ath12k_dp_link_peer_assign() to publish the dp_link_peer in the
> dp_hw->dp_peers[peerid_index] RCU table, in the dp_peer's
> link_peers[] array, and in the per-addr rhashtable.
> 
> If a step after ath12k_peer_create() fails the function jumps to
> err_peer_del, which open-codes a WMI peer_delete and waits for the
> unmap / delete_resp events. The wait_for_peer_delete_done() path
> relies on ath12k_dp_link_peer_unmap_event() freeing the dp_link_peer
> when the unmap arrives, but err_peer_del never calls
> ath12k_dp_link_peer_unassign() first. The published references in
> the dp_hw RCU table, dp_peer->link_peers[] and the rhashtable are
> left pointing at the dp_link_peer that unmap_event then frees,
> producing dangling pointers and use-after-free on subsequent
> lookups.
> 
> Replace the open-coded sequence with a call to ath12k_peer_delete(),
> which already does ath12k_dp_link_peer_unassign() before sending the
> WMI command. This drops the published references before the
> dp_link_peer is freed, in the same order as the normal teardown path
> in ath12k_mac_remove_link_interface().
> 
> Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3
> 
> Fixes: 5525f12fa671 ("wifi: ath12k: Attach and detach ath12k_dp_link_peer to ath12k_dp_peer")
> Signed-off-by: Baochen Qiang <baochen.qiang at oss.qualcomm.com>
Reviewed-by: Rameshkumar Sundaram <rameshkumar.sundaram at oss.qualcomm.com>