This is a note to let you know that I've just added the patch titled
wifi: ath9k: hif_usb: fix memory leak of urbs in ath9k_hif_usb_dealloc_tx_urbs()
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
wifi-ath9k-hif_usb-fix-memory-leak-of-urbs-in-ath9k_.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 2ceb82afcd225ff1fa6d38801e13d578abfd78ba
Author: Fedor Pchelkin <pchelkin@xxxxxxxxx>
Date: Mon Jul 25 18:13:59 2022 +0300
wifi: ath9k: hif_usb: fix memory leak of urbs in ath9k_hif_usb_dealloc_tx_urbs()
[ Upstream commit c2a94de38c74e86f49124ac14f093d6a5c377a90 ]
Syzkaller reports a long-known leak of urbs in
ath9k_hif_usb_dealloc_tx_urbs().
The cause of the leak is that usb_get_urb() is called but usb_free_urb()
(or usb_put_urb()) is not called inside usb_kill_urb() as urb->dev or
urb->ep fields have not been initialized and usb_kill_urb() returns
immediately.
The patch removes trying to kill urbs located in hif_dev->tx.tx_buf
because hif_dev->tx.tx_buf is not supposed to contain urbs which are in
pending state (the pending urbs are stored in hif_dev->tx.tx_pending).
The tx.tx_lock is acquired so there should not be any changes in the list.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 03fb92a432ea ("ath9k: hif_usb: fix race condition between usb_get_urb() and usb_kill_anchored_urbs()")
Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>
Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>
Acked-by: Toke Høiland-Jørgensen <toke@xxxxxxx>
Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220725151359.283704-1-pchelkin@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c
index c8c7afe0e343..4290753a2002 100644
--- a/drivers/net/wireless/ath/ath9k/hif_usb.c
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.c
@@ -781,14 +781,10 @@ static void ath9k_hif_usb_dealloc_tx_urbs(struct hif_device_usb *hif_dev)
spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
list_for_each_entry_safe(tx_buf, tx_buf_tmp,
&hif_dev->tx.tx_buf, list) {
- usb_get_urb(tx_buf->urb);
- spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
- usb_kill_urb(tx_buf->urb);
list_del(&tx_buf->list);
usb_free_urb(tx_buf->urb);
kfree(tx_buf->buf);
kfree(tx_buf);
- spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
}
spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
