This is a note to let you know that I've just added the patch titled net: Catch invalid index in XPS mapping to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-catch-invalid-index-in-xps-mapping.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ca0ad4aaf249e90045be963a9a21776a00f53053 Author: Nick Child <nnac123@xxxxxxxxxxxxx> Date: Tue Mar 21 10:07:24 2023 -0500 net: Catch invalid index in XPS mapping [ Upstream commit 5dd0dfd55baec0742ba8f5625a0dd064aca7db16 ] When setting the XPS value of a TX queue, warn the user once if the index of the queue is greater than the number of allocated TX queues. Previously, this scenario went uncaught. In the best case, it resulted in unnecessary allocations. In the worst case, it resulted in out-of-bounds memory references through calls to `netdev_get_tx_queue( dev, index)`. Therefore, it is important to inform the user but not worth returning an error and risk downing the netdevice. Signed-off-by: Nick Child <nnac123@xxxxxxxxxxxxx> Reviewed-by: Piotr Raczynski <piotr.raczynski@xxxxxxxxx> Link: https://lore.kernel.org/r/20230321150725.127229-1-nnac123@xxxxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/core/dev.c b/net/core/dev.c index b778f35965433..03903d3f1d695 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2303,6 +2303,8 @@ int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, bool active = false; unsigned int nr_ids; + WARN_ON_ONCE(index >= dev->num_tx_queues); + if (dev->num_tc) { /* Do not allow XPS on subordinate device directly */ num_tc = dev->num_tc;