bin/68683: [PATCH] cron: Fix parsing of '0' and non-alphanumerics in steps

[Xin LI]

>Number:         68683
>Category:       bin
>Synopsis:       [PATCH] cron: Fix parsing of '0' and non-alphanumerics in steps
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Mon Jul 05 09:30:13 GMT 2004
>Closed-Date:
>Last-Modified:
>Originator:     Xin LI
>Release:        FreeBSD 5.2-delphij i386
>Organization:
The FreeBSD Simplified Chinese Project
>Environment:
System: FreeBSD beastie.frontfree.net 5.2-delphij FreeBSD 5.2-delphij #80: Thu Jun 24 17:30:33 CST 2004 delphij at beastie.frontfree.net:/usr/obj/usr/src/sys/BEASTIE i386

>Description:
	Having an entry with stepping value of zero, say, */0, is currently
permitted by cron(5) however that will lead to a 100% CPU load. This should
be either documented in crontab(5), or be handled properly (preferred).
	The attached patch brings OpenBSD src/usr.sbin/cron/entry.c,v 1.17's
changes to FreeBSD, which will solve the issue.
>How-To-Repeat:
	Have a similiar line like this, in /etc/crontab
*/0    *       *       *       *       operator /usr/local/bin/test
>Fix:

--- patch-cron begins here ---
Index: entry.c
===================================================================
RCS file: /home/fcvs/src/usr.sbin/cron/lib/entry.c,v
retrieving revision 1.15
diff -u -r1.15 entry.c
--- entry.c	16 Aug 2001 14:23:59 -0000	1.15
+++ entry.c	5 Jul 2004 09:17:45 -0000
@@ -543,7 +543,7 @@
 		 * sent as a 0 since there is no offset either.
 		 */
 		ch = get_number(&num3, 0, PPC_NULL, ch, file);
-		if (ch == EOF)
+		if (ch == EOF || num3 == 0)
 			return EOF;
 	} else {
 		/* no step.  default==1.
@@ -592,6 +592,8 @@
 		ch = get_char(file);
 	}
 	*pc = '\0';
+	if (len == 0)
+	    return (EOF);
 
 	/* try to find the name in the name list
 	 */
--- patch-cron ends here ---


>Release-Note:
>Audit-Trail:
>Unformatted: