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 4.14-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-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 796771a56571b1e48a8944c921067db5ec4e2a98 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 8125f1752651..039f5d76685e 100644 --- a/drivers/net/wireless/ath/ath9k/hif_usb.c +++ b/drivers/net/wireless/ath/ath9k/hif_usb.c @@ -779,14 +779,10 @@ 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);