diff mbox series

[net,03/15] netfilter: ip6_tables: zero-initialize fragment offset

Message ID 20210924221113.348767-4-pablo@netfilter.org
State Accepted
Delegated to: Pablo Neira
Headers show
Series [net,01/15] netfilter: ipset: Fix oversized kvmalloc() calls | expand

Commit Message

Pablo Neira Ayuso Sept. 24, 2021, 10:11 p.m. UTC 
From: Jeremy Sowden <jeremy@azazel.net>

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 <jeremy@azazel.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/ipv6/netfilter/ip6_tables.c | 1 +
 1 file changed, 1 insertion(+)
diff mbox series

Patch

diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index de2cf3943b91..a579ea14a69b 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;