From: Qiujun Huang <hqjagain@xxxxxxxxx> commit 19d6c375d671ce9949a864fb9a03e19f5487b4d3 upstream. Add barrier to accessing the stack array skb_pool. The case reported by syzbot: https://lore.kernel.org/linux-usb/0000000000003d7c1505a2168418@xxxxxxxxxx BUG: KASAN: stack-out-of-bounds in ath9k_hif_usb_rx_stream drivers/net/wireless/ath/ath9k/hif_usb.c:626 [inline] BUG: KASAN: stack-out-of-bounds in ath9k_hif_usb_rx_cb+0xdf6/0xf70 drivers/net/wireless/ath/ath9k/hif_usb.c:666 Write of size 8 at addr ffff8881db309a28 by task swapper/1/0 Call Trace: ath9k_hif_usb_rx_stream drivers/net/wireless/ath/ath9k/hif_usb.c:626 [inline] ath9k_hif_usb_rx_cb+0xdf6/0xf70 drivers/net/wireless/ath/ath9k/hif_usb.c:666 __usb_hcd_giveback_urb+0x1f2/0x470 drivers/usb/core/hcd.c:1648 usb_hcd_giveback_urb+0x368/0x420 drivers/usb/core/hcd.c:1713 dummy_timer+0x1258/0x32ae drivers/usb/gadget/udc/dummy_hcd.c:1966 call_timer_fn+0x195/0x6f0 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x5f9/0x1500 kernel/time/timer.c:1786 Reported-and-tested-by: syzbot+d403396d4df67ad0bd5f@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Qiujun Huang <hqjagain@xxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200404041838.10426-5-hqjagain@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/ath/ath9k/hif_usb.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/net/wireless/ath/ath9k/hif_usb.c +++ b/drivers/net/wireless/ath/ath9k/hif_usb.c @@ -612,6 +612,11 @@ static void ath9k_hif_usb_rx_stream(stru hif_dev->remain_skb = nskb; spin_unlock(&hif_dev->rx_lock); } else { + if (pool_index == MAX_PKT_NUM_IN_TRANSFER) { + dev_err(&hif_dev->udev->dev, + "ath9k_htc: over RX MAX_PKT_NUM\n"); + goto err; + } nskb = __dev_alloc_skb(pkt_len + 32, GFP_ATOMIC); if (!nskb) { dev_err(&hif_dev->udev->dev,
