From 8c6680025b49f8d4c17e3ebfac5eec38786d59e9 Mon Sep 17 00:00:00 2001 From: Jeremy Sowden Date: Sun, 12 Sep 2021 22:24:33 +0100 Subject: [PATCH] netfilter: ip6_tables: zero-initialize fragment offset [ Upstream commit 310e2d43c3ad429c1fba4b175806cf1f55ed73a6 ] ip6tables only sets the `IP6T_F_PROTO` flag on a rule if a protocol is specified (`-p tcp`, for example). However, if the flag is not set, `ip6_packet_match` doesn't call `ipv6_find_hdr` for the skb, in which case the fragment offset is left uninitialized and a garbage value is passed to each matcher. Signed-off-by: Jeremy Sowden Reviewed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/ipv6/netfilter/ip6_tables.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 8bb543b0e775..41268612bdd4 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -273,6 +273,7 @@ ip6t_do_table(struct sk_buff *skb, * things we don't know, ie. tcp syn flag or ports). If the * rule is also a fragment-specific rule, non-fragments won't * match it. */ + acpar.fragoff = 0; acpar.hotdrop = false; acpar.state = state;