From 0bc1c0ae7ce61a7ac8a8e9a9b2086268f011abf0 Mon Sep 17 00:00:00 2001
From: Steve Dickson <steved@redhat.com>
Date: Tue, 9 Oct 2018 09:19:50 -0400
Subject: [PATCH] rpcinfo: Fix stack buffer overflow

buffer overflow detected: rpcinfo terminated
======= Backtrace: =========
/lib64/libc.so.6(+0x721af)[0x7ff24c4451af]
/lib64/libc.so.6(__fortify_fail+0x37)[0x7ff24c4ccdc7]
/lib64/libc.so.6(+0xf8050)[0x7ff24c4cb050]
rpcinfo(+0x435f)[0xef3be2635f]
rpcinfo(+0x1c62)[0xef3be23c62]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x7ff24c3f36e5]
rpcinfo(+0x2739)[0xef3be24739]
======= Memory map: ========
...
The patch below fixes it.

Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Thomas Blume <thomas.blume@suse.com>
Signed-off-by: Steve Dickson <steved@redhat.com>
---
 src/rpcinfo.c | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

--- a/src/rpcinfo.c
+++ b/src/rpcinfo.c
@@ -973,6 +973,7 @@ rpcbdump (dumptype, netid, argc, argv)
 	("   program version(s) netid(s)                         service     owner\n");
       for (rs = rs_head; rs; rs = rs->next)
 	{
+	  size_t netidmax = sizeof(buf) - 1;
 	  char *p = buf;
 
 	  printf ("%10ld  ", rs->prog);
@@ -985,12 +986,22 @@ rpcbdump (dumptype, netid, argc, argv)
 	    }
 	  printf ("%-10s", buf);
 	  buf[0] = '\0';
-	  for (nl = rs->nlist; nl; nl = nl->next)
-	    {
-	      strcat (buf, nl->netid);
-	      if (nl->next)
-		strcat (buf, ",");
-	    }
+
+          for (nl = rs->nlist; nl; nl = nl->next)
+            {
+              strncat (buf, nl->netid, netidmax);
+              if (strlen (nl->netid) < netidmax)
+                netidmax -= strlen(nl->netid);
+              else
+                break;
+
+              if (nl->next && netidmax > 1)
+                {
+                  strncat (buf, ",", netidmax);
+                  netidmax --;
+                }
+            }
+
 	  printf ("%-32s", buf);
 	  rpc = getrpcbynumber (rs->prog);
 	  if (rpc)