SEGV when auto.master in yp-server is with a blank line at last

[wengang wang <wen.gang.wang@oracle.com>]

Hi experts,

Recently I met a problem on RHEL5.1 with autofs-5.0.1-0.rc2.55

automount SEGV core dumps when running with configs:

/etc/auto.master
===
+auto.master
===


/etc/nsswitch.conf
===
automount:  files nis
===


ypcat -k auto.master | cat -A
===
/nfs/opsutils auto.opsutils^I^I-rw,soft$
/nfs/private auto.private^I-rw,intr,nosuid$
/nfs/roview auto.roview        -rw,intr,nosuid$
/nfs/group auto.group^I^I-rw,intr$
/nfs/floor auto.floor^I^I-ro,soft$
/nfs/net -hosts^I^I^I-ro,soft,nosuid$
/nfs/log auto.log-hq^I-rw,intr$
/netvobs auto.vobs^I-rw,hard,intr,nosuid$
/netview auto.view^I-rw,hard,intr,nosuid$
/home auto.home^I^I-rw,intr,nosuid$
/SCM auto.scm^I-rw,hard,intr,nosuid$
$

I found the core dump is caused by the last blank line in auto.master. 
and I wrote a patch on it.
--- ./modules/lookup_yp.c.bug   2008-02-27 22:50:26.000000000 -0500
+++ ./modules/lookup_yp.c       2008-02-27 22:51:40.000000000 -0500
@@ -175,6 +175,9 @@
        if (*ypkey == '+')
                return 0;
 
+       if (ypkeylen == 0)
+               return 0;
+
        *(ypkey + ypkeylen) = '\0';
        *(val + vallen) = '\0';
 
and seems this patch fixes the problem.

Is there anything wrong with the patch?

thanks,
wengang.