[src/trunk]: src/lib/libc/rpc Avoid broken state if realloc(3) fails.

[tron <tron%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/4c6f789db0eb
branches:  trunk
changeset: 341603:4c6f789db0eb
user:      tron <tron%NetBSD.org@localhost>
date:      Fri Nov 13 10:43:32 2015 +0000

description:
Avoid broken state if realloc(3) fails.

diffstat:

 lib/libc/rpc/svc.c |  15 ++++++++-------
 1 files changed, 8 insertions(+), 7 deletions(-)

diffs (48 lines):

diff -r b8ea17c5dbd4 -r 4c6f789db0eb lib/libc/rpc/svc.c
--- a/lib/libc/rpc/svc.c        Fri Nov 13 09:56:27 2015 +0000
+++ b/lib/libc/rpc/svc.c        Fri Nov 13 10:43:32 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: svc.c,v 1.36 2015/11/07 17:34:33 christos Exp $        */
+/*     $NetBSD: svc.c,v 1.37 2015/11/13 10:43:32 tron Exp $    */
 
 /*
  * Copyright (c) 2010, Oracle America, Inc.
@@ -37,7 +37,7 @@
 static char *sccsid = "@(#)svc.c 1.44 88/02/08 Copyr 1984 Sun Micro";
 static char *sccsid = "@(#)svc.c       2.4 88/08/11 4.0 RPCSRC";
 #else
-__RCSID("$NetBSD: svc.c,v 1.36 2015/11/07 17:34:33 christos Exp $");
+__RCSID("$NetBSD: svc.c,v 1.37 2015/11/13 10:43:32 tron Exp $");
 #endif
 #endif
 
@@ -131,7 +131,7 @@
 xprt_alloc(int sock)
 {
        int maxset;
-       char *newxports;
+       SVCXPRT **oldxports, **newxports;
 
        if (++sock < 0)
                return FALSE;
@@ -143,15 +143,16 @@
        if (__svc_xports != NULL && maxset <= __svc_maxxports)
                return TRUE;
 
-       if (__svc_xports != NULL)
-               --__svc_xports;
-       newxports = realloc(__svc_xports, maxset * sizeof(SVCXPRT *));
+       oldxports = __svc_xports;
+       if (oldxports != NULL)
+               --oldxports;
+       newxports = realloc(oldxports, maxset * sizeof(SVCXPRT *));
        if (newxports == NULL) {
                warn("%s: out of memory", __func__);
                return FALSE;
        }
 
-       memset(newxports + __svc_maxxports * sizeof(SVCXPRT *), 0,
+       memset(&newxports[__svc_maxxports], 0,
            (maxset - __svc_maxxports) * sizeof(SVCXPRT *));
 
        __svc_xports = (void *)newxports;