From: Antonio Quartulli <a@unstable.cc>
Date: Sat, 6 Jan 2018 18:31:50 +0000 (+0800)
Subject: ss: fix NULL pointer access when parsing unix sockets with oldformat
X-Git-Tag: v4.15.0~38
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ebbb219c924ccedbc59e209d40b77d5dbeecd7cd;p=thirdparty%2Fiproute2.git

ss: fix NULL pointer access when parsing unix sockets with oldformat

When parsing and printing the unix sockets in unix_show(),
if the oldformat is detected, the peer_name member of the sockstat
object is left uninitialized (NULL).
For this reason, if a filter has been specified on the command line,
a strcmp() will crash when trying to access it.

Avoid crash by checking that peer_name is not NULL before
passing it to strcmp().

Cc: Stefano Brivio <sbrivio@redhat.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---

diff --git a/misc/ss.c b/misc/ss.c
index b35859dc4..29a250704 100644
--- a/misc/ss.c
+++ b/misc/ss.c
@@ -3711,7 +3711,10 @@ static int unix_show(struct filter *f)
 			};
 
 			memcpy(st.local.data, &u->name, sizeof(u->name));
-			if (strcmp(u->peer_name, "*"))
+			/* when parsing the old format rport is set to 0 and
+			 * therefore peer_name remains NULL
+			 */
+			if (u->peer_name && strcmp(u->peer_name, "*"))
 				memcpy(st.remote.data, &u->peer_name,
 				       sizeof(u->peer_name));
 			if (run_ssfilter(f->f, &st) == 0) {