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From de7ba61cf107f43223eeb640267d24e187047c29 Mon Sep 17 00:00:00 2001
From: Phil Sutter <psutter@redhat.com>
Date: Fri, 15 Mar 2019 17:51:28 +0100
Subject: [PATCH] libxt_conntrack: Avoid potential buffer overrun

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1525980
Upstream Status: iptables commit 8e798e050367d

commit 8e798e050367dfe43bb958f11dd3170b03bda49e
Author: Phil Sutter <phil@nwl.cc>
Date:   Wed Sep 19 15:16:50 2018 +0200

    libxt_conntrack: Avoid potential buffer overrun

    In print_addr(), a resolved hostname is written into a buffer without
    size check. Since BUFSIZ is typically 8192 bytes, this shouldn't be an
    issue, though covscan complained about it. Fix the code by using
    conntrack_dump_addr() as an example.

    Signed-off-by: Phil Sutter <phil@nwl.cc>
    Signed-off-by: Florian Westphal <fw@strlen.de>

Signed-off-by: Phil Sutter <psutter@redhat.com>
---
 extensions/libxt_conntrack.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/extensions/libxt_conntrack.c b/extensions/libxt_conntrack.c
index 3e7075760d40f..804aa23638ca1 100644
--- a/extensions/libxt_conntrack.c
+++ b/extensions/libxt_conntrack.c
@@ -673,20 +673,20 @@ static void
 print_addr(const struct in_addr *addr, const struct in_addr *mask,
            int inv, int numeric)
 {
-	char buf[BUFSIZ];
-
 	if (inv)
 		printf(" !");
 
 	if (mask->s_addr == 0L && !numeric)
-		printf(" %s", "anywhere");
+		printf(" anywhere");
 	else {
 		if (numeric)
-			strcpy(buf, xtables_ipaddr_to_numeric(addr));
+			printf(" %s%s",
+			       xtables_ipaddr_to_numeric(addr),
+			       xtables_ipmask_to_numeric(mask));
 		else
-			strcpy(buf, xtables_ipaddr_to_anyname(addr));
-		strcat(buf, xtables_ipmask_to_numeric(mask));
-		printf(" %s", buf);
+			printf(" %s%s",
+			       xtables_ipaddr_to_anyname(addr),
+			       xtables_ipmask_to_numeric(mask));
 	}
 }
 
-- 
2.21.0