FAILED: patch "[PATCH] wifi: mt76: mt7603: initialize global station WCID" failed to apply to 6.12-stable tree

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 456de496b53ae73e6e3020fec815dbdc88aa7c07
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026101201-cathouse-overhand-5997@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 456de496b53ae73e6e3020fec815dbdc88aa7c07 Mon Sep 17 00:00:00 2001
From: Cristian Papa <[email protected]>
Date: Thu, 3 Sep 2026 22:07:02 -0300
Subject: [PATCH] wifi: mt76: mt7603: initialize global station WCID

mt7603 uses a driver-private global station WCID for frames that have neither a station nor a vif, including frames injected through a monitor interface. Unlike the core global WCID initialized by mt76_register_device(), this WCID is published without ever being passed to mt76_wcid_init().

Since commit 0335c034e726 ("wifi: mt76: fix race condition related to checking tx queue fill status"), mt76_tx() queues every such frame on the WCID's tx_pending or tx_offchannel queue and links its tx_list. The first injected frame therefore reaches __skb_queue_tail() with an uninitialized sk_buff_head and dereferences a NULL prev pointer.

Initialize the WCID before publishing it.

The fix was tested on an MT7603 PCIe device. Three wildcard probe requests were injected through a monitor interface. The hardware queue head and tail advanced from 0 to 3 and a second radio captured the third request over the air. No oops or reset occurred. After restoring AP mode, a 150 MB transfer also completed without a reset.

index 10f2ec70c792..218ec406d2a8 100644
@@ -230,6 +230,7 @@ mt7603_mac_init(struct mt7603_dev *dev)
 
 	eth_broadcast_addr(bc_addr);
 	mt7603_wtbl_init(dev, MT7603_WTBL_RESERVED, -1, bc_addr);
+	mt76_wcid_init(&dev->global_sta.wcid, 0);
 	dev->global_sta.wcid.idx = MT7603_WTBL_RESERVED;
 	rcu_assign_pointer(dev->mt76.wcid[MT7603_WTBL_RESERVED],
 			   &dev->global_sta.wcid);

commit 456de496b53ae73e6e3020fec815dbdc88aa7c07 upstream.

mt7603 uses a driver-private global station WCID for frames that have neither a station nor a vif, including frames injected through a monitor interface. Unlike the core global WCID initialized by mt76_register_device(), this WCID is published without ever being passed to mt76_wcid_init().

Since commit 0335c034e726 ("wifi: mt76: fix race condition related to checking tx queue fill status"), mt76_tx() queues every such frame on the WCID's tx_pending or tx_offchannel queue and links its tx_list. The first injected frame therefore reaches __skb_queue_tail() with an uninitialized sk_buff_head and dereferences a NULL prev pointer.

Initialize the WCID before publishing it.

The fix was tested on an MT7603 PCIe device. Three wildcard probe requests were injected through a monitor interface. The hardware queue head and tail advanced from 0 to 3 and a second radio captured the third request over the air. No oops or reset occurred. After restoring AP mode, a 150 MB transfer also completed without a reset.

---
 drivers/net/wireless/mediatek/mt76/mt7603/init.c | 1 +
 1 file changed, 1 insertion(+)

index 86617a3e4..64dccd039 100644
@@ -230,6 +230,7 @@ mt7603_mac_init(struct mt7603_dev *dev)
 
 	eth_broadcast_addr(bc_addr);
 	mt7603_wtbl_init(dev, MT7603_WTBL_RESERVED, -1, bc_addr);
+	mt76_wcid_init(&dev->global_sta.wcid);
 	dev->global_sta.wcid.idx = MT7603_WTBL_RESERVED;
 	rcu_assign_pointer(dev->mt76.wcid[MT7603_WTBL_RESERVED],
 			   &dev->global_sta.wcid);

2.47.3

Queued for 6.12, thanks.

Thanks,
Sasha