From: YueHaibing yuehaibing@huawei.com
[ 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@huawei.com Link: https://lore.kernel.org/r/20221125075724.27912-1-yuehaibing@huawei.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/hsr/hsr_forward.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c index a50429a62f74..56bb27d67a2e 100644 --- a/net/hsr/hsr_forward.c +++ b/net/hsr/hsr_forward.c @@ -351,17 +351,18 @@ 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++; }