[2624] in Kerberos-V5-bugs
krb5-appl/335: When using POSIX signals, rlogin doesn't clear them properly
daemon@ATHENA.MIT.EDU (Ken Hornstein)
Mon Jan 6 23:54:21 1997
Resent-From: gnats@rt-11.MIT.EDU (GNATS Management)
Resent-To: krb5-unassigned@RT-11.MIT.EDU
Resent-Reply-To: krb5-bugs@MIT.EDU, kenh@cmf.nrl.navy.mil
Date: Mon, 6 Jan 1997 23:53:13 -0500 (EST)
From: Ken Hornstein <kenh@cmf.nrl.navy.mil>
Reply-To: kenh@cmf.nrl.navy.mil
To: krb5-bugs@MIT.EDU
>Number: 335
>Category: krb5-appl
>Synopsis: On systems with POSIX signals, rlogin doesn't clear them
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: krb5-unassigned
>State: open
>Class: sw-bug
>Submitter-Id: unknown
>Arrival-Date: Mon Jan 06 23:54:00 EST 1997
>Last-Modified:
>Originator: Ken Hornstein
>Organization:
Naval Research Lab
>Release: 1.0
>Environment:
System: SunOS nexus 4.1.4 1 sun4m
Architecture: sun4
>Description:
Rlogin will try to run the regular Unix rlogin if the Kerberos one fails.
However, if your system supports POSIX signals, there is a subtle problem.
The Kerberos rlogin does not clear the signal mask before it tries running
the regular rlogin; as a result, some rlogins will not get SIGUSR1 during
startup and will not send the window size.
>How-To-Repeat:
Run Kerberos rlogin on a system that supports POSIX signals (like NetBSD)
to host that doesn't support Kerberos. Note that your window size isn't
passed.
>Fix:
--- krlogin.c.orig Mon Jan 6 23:45:33 1997
+++ krlogin.c Mon Jan 6 23:46:53 1997
@@ -1570,6 +1570,10 @@
char **argv;
{
register char *host;
+#ifdef POSIX_SIGNALS
+ struct sigaction sa;
+ sigest_t mask;
+#endif
#ifndef KRB5_ATHENA_COMPAT
if (encrypt_flag)
@@ -1587,6 +1591,11 @@
if (!strcmp(host, "rlogin"))
argv++;
+#ifdef POSIX_SIGNALS
+ sigemptyset(&mask)
+ sigprocmask(SIG_SETMASK, &mask, NULL);
+#endif
+
execv(UCB_RLOGIN, argv);
perror("exec");
exit(1);
>Audit-Trail:
>Unformatted:
