From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Westphal Subject: [PATCH 2/5] netfilter: x_tables: make sure e->next_offset covers remaining blob size Date: Tue, 22 Mar 2016 18:02:50 +0100 Message-ID: <1458666173-24318-3-git-send-email-fw@strlen.de> References: <1458666173-24318-1-git-send-email-fw@strlen.de> Cc: Florian Westphal To: Return-path: Received: from Chamillionaire.breakpoint.cc ([80.244.247.6]:38137 "EHLO Chamillionaire.breakpoint.cc" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756167AbcCVRCn (ORCPT ); Tue, 22 Mar 2016 13:02:43 -0400 In-Reply-To: <1458666173-24318-1-git-send-email-fw@strlen.de> Sender: netfilter-devel-owner@vger.kernel.org List-ID: Otherwise this function may read data beyond the ruleset blob. Signed-off-by: Florian Westphal --- net/ipv4/netfilter/arp_tables.c | 6 ++++-- net/ipv4/netfilter/ip_tables.c | 6 ++++-- net/ipv6/netfilter/ip6_tables.c | 6 ++++-- 3 files changed, 12 insertions(+), 6 deletions(-) diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index 830bbe8..51d4fe5 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -573,7 +573,8 @@ static inline int check_entry_size_and_hooks(struct arpt_entry *e, int err; if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 || - (unsigned char *)e + sizeof(struct arpt_entry) >= limit) { + (unsigned char *)e + sizeof(struct arpt_entry) >= limit || + (unsigned char *)e + e->next_offset > limit) { duprintf("Bad offset %p\n", e); return -EINVAL; } @@ -1232,7 +1233,8 @@ check_compat_entry_size_and_hooks(struct compat_arpt_entry *e, duprintf("check_compat_entry_size_and_hooks %p\n", e); if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 || - (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit) { + (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit || + (unsigned char *)e + e->next_offset > limit) { duprintf("Bad offset %p, limit = %p\n", e, limit); return -EINVAL; } diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 1d72a3c..fb7694e 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -738,7 +738,8 @@ check_entry_size_and_hooks(struct ipt_entry *e, int err; if ((unsigned long)e % __alignof__(struct ipt_entry) != 0 || - (unsigned char *)e + sizeof(struct ipt_entry) >= limit) { + (unsigned char *)e + sizeof(struct ipt_entry) >= limit || + (unsigned char *)e + e->next_offset > limit) { duprintf("Bad offset %p\n", e); return -EINVAL; } @@ -1492,7 +1493,8 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, duprintf("check_compat_entry_size_and_hooks %p\n", e); if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0 || - (unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit) { + (unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit || + (unsigned char *)e + e->next_offset > limit) { duprintf("Bad offset %p, limit = %p\n", e, limit); return -EINVAL; } diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 26a5ad1..b248528f 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -750,7 +750,8 @@ check_entry_size_and_hooks(struct ip6t_entry *e, int err; if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 || - (unsigned char *)e + sizeof(struct ip6t_entry) >= limit) { + (unsigned char *)e + sizeof(struct ip6t_entry) >= limit || + (unsigned char *)e + e->next_offset > limit) { duprintf("Bad offset %p\n", e); return -EINVAL; } @@ -1504,7 +1505,8 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e, duprintf("check_compat_entry_size_and_hooks %p\n", e); if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 || - (unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit) { + (unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit || + (unsigned char *)e + e->next_offset > limit) { duprintf("Bad offset %p, limit = %p\n", e, limit); return -EINVAL; } -- 2.4.10