From: Fedor Pchelkin pchelkin@ispras.ru
[ 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@ispras.ru Signed-off-by: Alexey Khoroshilov khoroshilov@ispras.ru Acked-by: Toke Høiland-Jørgensen toke@toke.dk Signed-off-by: Kalle Valo quic_kvalo@quicinc.com Link: https://lore.kernel.org/r/20220725151359.283704-1-pchelkin@ispras.ru Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/ath/ath9k/hif_usb.c | 4 ---- 1 file changed, 4 deletions(-)
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);