2b7c5eed19
commit 0c57eeecc559ca6bc18b8c4e2808bc78dbe769b0 upstream.
Drivers call netdev_set_num_tc() and then netdev_set_tc_queue()
to set the queue count and offset for each TC. So the queue count
and offset for the TCs may be zero for a short period after dev->num_tc
has been set. If a TX packet is being transmitted at this time in the
code path netdev_pick_tx() -> skb_tx_hash(), skb_tx_hash() may see
nonzero dev->num_tc but zero qcount for the TC. The while loop that
keeps looping while hash >= qcount will not end.
Fix it by checking the TC's qcount to be nonzero before using it.
Fixes: eadec877ce9c ("net: Add support for subordinate traffic classes to netdev_pick_tx")
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.