Add the missing endpoint max-packet sanity check to probe() to avoid division by zero in ath10k_usb_hif_tx_sg() in case a malicious device has broken descriptors (or when doing descriptor fuzz testing).

Note that USB core will reject URBs submitted for endpoints with zero wMaxPacketSize but that drivers doing packet-size calculations still need to handle this (cf. commit 2548288b4fb0 ("USB: Fix: Don't skip endpoint descriptors with maxpacket=0")).

Fixes: 4db66499df91 ("ath10k: add initial USB support") Cc: stable@vger.kernel.org # 4.14 Cc: Erik Stromdahl erik.stromdahl@gmail.com Signed-off-by: Johan Hovold johan@kernel.org --- drivers/net/wireless/ath/ath10k/usb.c | 5 +++++ 1 file changed, 5 insertions(+)

diff --git a/drivers/net/wireless/ath/ath10k/usb.c b/drivers/net/wireless/ath/ath10k/usb.c index 6d831b098cbb..3d98f19c6ec8 100644 --- a/drivers/net/wireless/ath/ath10k/usb.c +++ b/drivers/net/wireless/ath/ath10k/usb.c @@ -853,6 +853,11 @@ static int ath10k_usb_setup_pipe_resources(struct ath10k *ar, le16_to_cpu(endpoint->wMaxPacketSize), endpoint->bInterval); } + + /* Ignore broken descriptors. */ + if (usb_endpoint_maxp(endpoint) == 0) + continue; + urbcount = 0;

pipe_num =