This is a note to let you know that I've just added the patch titled
net: hsr: Fix potential use-after-free
to the 4.9-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-hsr-fix-potential-use-after-free.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit fa76d5085acf6ecf17d72c2c0835ae8f1946ab72
Author: YueHaibing <yuehaibing@xxxxxxxxxx>
Date: Fri Nov 25 15:57:24 2022 +0800
net: hsr: Fix potential use-after-free
[ Upstream commit 7e177d32442b7ed08a9fa61b61724abc548cb248 ]
The skb is delivered to netif_rx() which may free it, after calling this,
dereferencing skb may trigger use-after-free.
Fixes: f421436a591d ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221125075724.27912-1-yuehaibing@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
index 04b5450c5a55..adfb49760678 100644
--- a/net/hsr/hsr_forward.c
+++ b/net/hsr/hsr_forward.c
@@ -207,17 +207,18 @@ static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,
struct hsr_node *node_src)
{
bool was_multicast_frame;
- int res;
+ int res, recv_len;
was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
hsr_addr_subst_source(node_src, skb);
skb_pull(skb, ETH_HLEN);
+ recv_len = skb->len;
res = netif_rx(skb);
if (res == NET_RX_DROP) {
dev->stats.rx_dropped++;
} else {
dev->stats.rx_packets++;
- dev->stats.rx_bytes += skb->len;
+ dev->stats.rx_bytes += recv_len;
if (was_multicast_frame)
dev->stats.multicast++;
}
