[3.8.y.z,extended,stable] Patch "netfilter: ipt_ULOG: fix non-null terminated string in the" has been added to staging queue

Message ID 1373387367-23172-1-git-send-email-luis.henriques@canonical.com
State New
Headers show

Commit Message

Luis Henriques July 9, 2013, 4:29 p.m.
This is a note to let you know that I have just added a patch titled

    netfilter: ipt_ULOG: fix non-null terminated string in the

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:


If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see



From b2db6f1233497195ce29eb98423b3ed56bdc1434 Mon Sep 17 00:00:00 2001
From: Chen Gang <gang.chen@asianux.com>
Date: Thu, 23 May 2013 01:50:46 +0000
Subject: [PATCH] netfilter: ipt_ULOG: fix non-null terminated string in the
 nf_log path

commit 4f36ea6eed2081340c7a7aa98c73187ecfccebff upstream.

If nf_log uses ipt_ULOG as logging output, we can deliver non-null
terminated strings to user-space since the maximum length of the
prefix that is passed by nf_log is NF_LOG_PREFIXLEN but pm->prefix
is 32 bytes long (ULOG_PREFIX_LEN).

This is actually happening already from nf_conntrack_tcp if ipt_ULOG
is used, since it is passing strings longer than 32 bytes.

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
 net/ipv4/netfilter/ipt_ULOG.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)



diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c
index b5ef3cb..db5f368 100644
--- a/net/ipv4/netfilter/ipt_ULOG.c
+++ b/net/ipv4/netfilter/ipt_ULOG.c
@@ -217,8 +217,10 @@  static void ipt_ulog_packet(unsigned int hooknum,
 	put_unaligned(tv.tv_usec, &pm->timestamp_usec);
 	put_unaligned(skb->mark, &pm->mark);
 	pm->hook = hooknum;
-	if (prefix != NULL)
-		strncpy(pm->prefix, prefix, sizeof(pm->prefix));
+	if (prefix != NULL) {
+		strncpy(pm->prefix, prefix, sizeof(pm->prefix) - 1);
+		pm->prefix[sizeof(pm->prefix) - 1] = '\0';
+	}
 	else if (loginfo->prefix[0] != '\0')
 		strncpy(pm->prefix, loginfo->prefix, sizeof(pm->prefix));