Hello,
On Sun, Apr 20, 2025 at 11:00:53AM -0400, Sasha Levin wrote:
This is a note to let you know that I've just added the patch titled
wifi: mac80211: Update skb's control block key in ieee80211_tx_dequeue()
to the 6.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is:
wifi-mac80211-update-skb-s-control-block-key-in-ieee.patch
and it can be found in the queue-6.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let stable@vger.kernel.org know about it.
Not sure this patch should go to stable. @Johannes haven't you revert
it in your tree ?
Thanks,
--
Remi
>
>
> commit 9209089b629b7c29ae393cded89e77c169f18dfb
> Author: Remi Pommarel
repk@triplefau.lt
> Date: Mon Mar 24 17:28:20 2025 +0100
>
> wifi: mac80211: Update skb's control block key in ieee80211_tx_dequeue()
>
> [ Upstream commit a104042e2bf6528199adb6ca901efe7b60c2c27f ]
>
> The ieee80211 skb control block key (set when skb was queued) could have
> been removed before ieee80211_tx_dequeue() call. ieee80211_tx_dequeue()
> already called ieee80211_tx_h_select_key() to get the current key, but
> the latter do not update the key in skb control block in case it is
> NULL. Because some drivers actually use this key in their TX callbacks
> (e.g. ath1{1,2}k_mac_op_tx()) this could lead to the use after free
> below:
>
> BUG: KASAN: slab-use-after-free in ath11k_mac_op_tx+0x590/0x61c
> Read of size 4 at addr ffffff803083c248 by task kworker/u16:4/1440
>
> CPU: 3 UID: 0 PID: 1440 Comm: kworker/u16:4 Not tainted 6.13.0-ge128f627f404 #2
> Hardware name: HW (DT)
> Workqueue: bat_events batadv_send_outstanding_bcast_packet
> Call trace:
> show_stack+0x14/0x1c (C)
> dump_stack_lvl+0x58/0x74
> print_report+0x164/0x4c0
> kasan_report+0xac/0xe8
> __asan_report_load4_noabort+0x1c/0x24
> ath11k_mac_op_tx+0x590/0x61c
> ieee80211_handle_wake_tx_queue+0x12c/0x1c8
> ieee80211_queue_skb+0xdcc/0x1b4c
> ieee80211_tx+0x1ec/0x2bc
> ieee80211_xmit+0x224/0x324
> __ieee80211_subif_start_xmit+0x85c/0xcf8
> ieee80211_subif_start_xmit+0xc0/0xec4
> dev_hard_start_xmit+0xf4/0x28c
> __dev_queue_xmit+0x6ac/0x318c
> batadv_send_skb_packet+0x38c/0x4b0
> batadv_send_outstanding_bcast_packet+0x110/0x328
> process_one_work+0x578/0xc10
> worker_thread+0x4bc/0xc7c
> kthread+0x2f8/0x380
> ret_from_fork+0x10/0x20
>
> Allocated by task 1906:
> kasan_save_stack+0x28/0x4c
> kasan_save_track+0x1c/0x40
> kasan_save_alloc_info+0x3c/0x4c
> __kasan_kmalloc+0xac/0xb0
> __kmalloc_noprof+0x1b4/0x380
> ieee80211_key_alloc+0x3c/0xb64
> ieee80211_add_key+0x1b4/0x71c
> nl80211_new_key+0x2b4/0x5d8
> genl_family_rcv_msg_doit+0x198/0x240
> <...>
>
> Freed by task 1494:
> kasan_save_stack+0x28/0x4c
> kasan_save_track+0x1c/0x40
> kasan_save_free_info+0x48/0x94
> __kasan_slab_free+0x48/0x60
> kfree+0xc8/0x31c
> kfree_sensitive+0x70/0x80
> ieee80211_key_free_common+0x10c/0x174
> ieee80211_free_keys+0x188/0x46c
> ieee80211_stop_mesh+0x70/0x2cc
> ieee80211_leave_mesh+0x1c/0x60
> cfg80211_leave_mesh+0xe0/0x280
> cfg80211_leave+0x1e0/0x244
> <...>
>
> Reset SKB control block key before calling ieee80211_tx_h_select_key()
> to avoid that.
>
> Fixes: bb42f2d13ffc ("mac80211: Move reorder-sensitive TX handlers to after TXQ dequeue")
> Signed-off-by: Remi Pommarel
repk@triplefau.lt
> Link:
https://patch.msgid.link/06aa507b853ca385ceded81c18b0a6dd0f081bc8.1742833382...
> Signed-off-by: Johannes Berg
johannes.berg@intel.com
> Signed-off-by: Sasha Levin
sashal@kernel.org
>
> diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
> index a24636bda6793..0c6214f12ea39 100644
> --- a/net/mac80211/tx.c
> +++ b/net/mac80211/tx.c
> @@ -3893,6 +3893,7 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
> * The key can be removed while the packet was queued, so need to call
> * this here to get the current key.
> */
> + info->control.hw_key = NULL;
> r = ieee80211_tx_h_select_key(&tx);
> if (r != TX_CONTINUE) {
> ieee80211_free_txskb(&local->hw, skb);