From: Pablo Neira Ayuso pablo@netfilter.org
stable inclusion from linux-4.19.198 commit 0cb785dd9e42be71ec92fee8ef984c0a1e64dab3
--------------------------------
[ Upstream commit cdd73cc545c0fb9b1a1f7b209f4f536e7990cff4 ]
ipv6_find_hdr() does not validate that this is an IPv6 packet. Add a sanity check for calling ipv6_find_hdr() to make sure an IPv6 packet is passed for parsing.
Fixes: 96518518cc41 ("netfilter: add nftables") Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- net/netfilter/nft_exthdr.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/netfilter/nft_exthdr.c b/net/netfilter/nft_exthdr.c index a940c9fd9045e..64e69d6683cab 100644 --- a/net/netfilter/nft_exthdr.c +++ b/net/netfilter/nft_exthdr.c @@ -45,6 +45,9 @@ static void nft_exthdr_ipv6_eval(const struct nft_expr *expr, unsigned int offset = 0; int err;
+ if (pkt->skb->protocol != htons(ETH_P_IPV6)) + goto err; + err = ipv6_find_hdr(pkt->skb, &offset, priv->type, NULL, NULL); if (priv->flags & NFT_EXTHDR_F_PRESENT) { *dest = (err >= 0);