Hello. On 24-01-2013 14:25, Bjørn Mork wrote:
A device sending 0 length frames as fast as it can has been observed killing the host system due to the resulting memory pressure. We handle the done queue as fast as we can, so if this queue is filling up then that is an indication that we are under too heavy pressure. Refusing further allocations until the done queue is handled prevents the buggy device from taking the system down. Signed-off-by: Bjørn Mork <bjorn@xxxxxxx>
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drivers/net/usb/usbnet.c | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index f34b2eb..85c7ffd 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -380,6 +380,14 @@ static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags) unsigned long lockflags; size_t size = dev->rx_urb_size; + /* Do not let a device flood us to death! */ + if (dev->done.qlen > 1024) { + netif_dbg(dev, rx_err, dev->net, "done queue filling up (%u) - throttling\n", dev->done.qlen); + usbnet_defer_kevent (dev, EVENT_RX_MEMORY); + usb_free_urb (urb);
Run your patch thru scripts/checkpatch.pl please -- spaces before parens are not allowed.
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