linux-kernel - [PATCH 3.13 055/212] ipv6: fix calculation of option len in ip6_append

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1403041506-13646-56-git-send-email-kamal@canonical.com>
Date:	Tue, 17 Jun 2014 14:42:29 -0700
From:	Kamal Mostafa <kamal@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	Hannes Frederic Sowa <hannes@...essinduktion.org>,
	"David S. Miller" <davem@...emloft.net>,
	Kamal Mostafa <kamal@...onical.com>
Subject: [PATCH 3.13 055/212] ipv6: fix calculation of option len in ip6_append_data

3.13.11.4 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Hannes Frederic Sowa <hannes@...essinduktion.org>

[ Upstream commit 3a1cebe7e05027a1c96f2fc1a8eddf5f19b78f42 ]

tot_len does specify the size of struct ipv6_txoptions. We need opt_flen +
opt_nflen to calculate the overall length of additional ipv6 extensions.

I found this while auditing the ipv6 output path for a memory corruption
reported by Alexey Preobrazhensky while he fuzzed an instrumented
AddressSanitizer kernel with trinity. This may or may not be the cause
of the original bug.

Fixes: 4df98e76cde7c6 ("ipv6: pmtudisc setting not respected with UFO/CORK")
Reported-by: Alexey Preobrazhensky <preobr@...gle.com>
Signed-off-by: Hannes Frederic Sowa <hannes@...essinduktion.org>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Kamal Mostafa <kamal@...onical.com>
---
 net/ipv6/ip6_output.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 92bc3b4..e86c22e 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1216,7 +1216,7 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
 		unsigned int maxnonfragsize, headersize;
 
 		headersize = sizeof(struct ipv6hdr) +
-			     (opt ? opt->tot_len : 0) +
+			     (opt ? opt->opt_flen + opt->opt_nflen : 0) +
 			     (dst_allfrag(&rt->dst) ?
 			      sizeof(struct frag_hdr) : 0) +
 			     rt->rt6i_nfheader_len;
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/