bin/100585: [PATCH] top -s0 causes load excessive

[Bruce Evans]

The following reply was made to PR bin/100585; it has been noted by GNATS.

From: Bruce Evans <bde at zeta.org.au>
To: Roberto Lima <roberto at forbrazil.com.br>
Cc: freebsd-gnats-submit at FreeBSD.org, freebsd-bugs at FreeBSD.org,
        dwmalone at FreeBSD.org
Subject: Re: bin/100585: [PATCH] top -s0 causes load excessive
Date: Mon, 24 Jul 2006 17:14:22 +1000 (EST)

 On Wed, 19 Jul 2006, Roberto Lima wrote:
 
 >> Description:
 > I see that my costumers have been used 'top -s0' too many times and this is overloading in my system.
 >> How-To-Repeat:
 > just use 'top -s0' and see the load average going up.
 >> Fix:
 > --- top.c.old   Wed Jul 19 19:49:23 2006
 > +++ top.c       Wed Jul 19 19:49:32 2006
 > @@ -331,7 +331,7 @@
 >                break;
 >
 >              case 's':
 > -               if ((delay = atoi(optarg)) < 0 || (delay == 0 && getuid() != 0))
 > +               if ((delay = atoi(optarg)) < 1 || (delay == 0 && getuid() != 0))
 
 This would just break the feature that a delay of 0 works for non-root.
 It is already broken for root.  top hasn't used kmem or been setuid
 for a long time so it shouldn't call getuid() here or elsewhere.  Users
 who wish to overload the system can do it in more or less interesting ways
 than with "top -s0", e.g., with "while :; do top 15 | cat; done".
 
 Bruce