Subject: [PATCH] ip6tables: Read outside array bounds

From: Roel Kluin <[email-masked]>
Date: Thu, 27 Aug 2009 13:23:00 +0200

Check bounds before reading from the s6_addr array. It read 1 past
the end at s6_addr[16] and eui64[] was also read 1 past the end.

Signed-off-by: Roel Kluin <[email-masked]>
---
diff --git a/net/ipv6/netfilter/ip6t_eui64.c b/net/ipv6/netfilter/ip6t_eui64.c
index db610ba..7b40a20 100644
--- a/net/ipv6/netfilter/ip6t_eui64.c
+++ b/net/ipv6/netfilter/ip6t_eui64.c
@@ -43,8 +43,8 @@ eui64_mt6(const struct sk_buff *skb, const struct xt_match_param *par)
 			eui64[0] ^= 0x02;
 
 			i = 0;
-			while (ipv6_hdr(skb)->saddr.s6_addr[8 + i] == eui64[i]
-			       && i < 8)
+			while (i < 8 && ipv6_hdr(skb)->saddr.s6_addr[8 + i] ==
+					eui64[i])
 				i++;
 
 			if (i == 8)