Re: [syzbot] [net?] WARNING in mpls_gso_segment

Lizhi Xu
2024-02-22T03:15:49Z

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git main

diff --git a/net/mpls/mpls_gso.c b/net/mpls/mpls_gso.c
index 533d082f0701..2ab24b2fd90f 100644
--- a/net/mpls/mpls_gso.c
+++ b/net/mpls/mpls_gso.c
@@ -25,11 +25,11 @@ static struct sk_buff *mpls_gso_segment(struct sk_buff *skb,
netdev_features_t mpls_features;
u16 mac_len = skb->mac_len;
__be16 mpls_protocol;
- unsigned int mpls_hlen;
+ int mpls_hlen;

skb_reset_network_header(skb);
mpls_hlen = skb_inner_network_header(skb) - skb_network_header(skb);
- if (unlikely(!mpls_hlen || mpls_hlen % MPLS_HLEN))
+ if (unlikely(mpls_hlen <= 0 || mpls_hlen % MPLS_HLEN))
goto out;
if (unlikely(!pskb_may_pull(skb, mpls_hlen)))
goto out;