From owner-freebsd-bugs Fri Dec 25 21:30:11 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id VAA03814 for freebsd-bugs-outgoing; Fri, 25 Dec 1998 21:30:11 -0800 (PST) (envelope-from owner-freebsd-bugs@FreeBSD.ORG) Received: from freefall.freebsd.org (freefall.FreeBSD.ORG [204.216.27.21]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id VAA03806 for ; Fri, 25 Dec 1998 21:30:10 -0800 (PST) (envelope-from gnats@FreeBSD.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.8.8/8.8.5) id VAA28928; Fri, 25 Dec 1998 21:30:01 -0800 (PST) Received: from po2.glue.umd.edu (po2.glue.umd.edu [129.2.128.45]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id VAA03116 for ; Fri, 25 Dec 1998 21:22:18 -0800 (PST) (envelope-from jgarman@Glue.umd.edu) Received: from y.glue.umd.edu ((IDENT root)@y.glue.umd.edu [128.8.10.68]) by po2.glue.umd.edu (8.9.0.Beta6/8.9.0.Beta6) with ESMTP id AAA25023 for ; Sat, 26 Dec 1998 00:22:00 -0500 (EST) Received: from y.glue.umd.edu ((IDENT sendmail)@localhost [127.0.0.1]) by y.glue.umd.edu (8.9.0.Beta6/8.9.0.Beta6) with SMTP id AAA28354 for ; Sat, 26 Dec 1998 00:22:01 -0500 (EST) Received: from localhost by y.glue.umd.edu (8.9.0.Beta6/8.9.0.Beta6) with SMTP id AAA28336 for ; Sat, 26 Dec 1998 00:22:00 -0500 (EST) Message-Id: Date: Sat, 26 Dec 1998 00:22:00 -0500 (EST) From: Jason Garman To: FreeBSD-gnats-submit@FreeBSD.ORG Subject: kern/9195: daemons die with sig11 due to VM problems Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org >Number: 9195 >Category: kern >Synopsis: daemons die with sig11 due to VM problems >Confidential: no >Severity: critical >Priority: high >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Fri Dec 25 21:30:01 PST 1998 >Last-Modified: >Originator: Jason Garman >Organization: individual >Release: FreeBSD 3.0-CURRENT i386 >Environment: FreeBSD jason.garman.net 3.0-CURRENT FreeBSD 3.0-CURRENT #5: Wed Dec 23 22:01:40 EST 1998 root@jason.garman.net:/usr/src/sys/compile/JASON i386 on a PII/300 with 96MB of real memory, 150MB of swap >Description: When a "significant" amount of swap is used on this system ("significant" can be any number from 50% on up) then daemons that fork die with sigsegv's due to null pointer accesses. ie. it seems that particular portions of the child processes' memory has been cleared. >How-To-Repeat: Make the machine swap. Try and get the daemon you want to segfault to swap out of memory... then make it fork a few times. It'll start segfaulting. It seems to correlate with the following message in syslog: swap_pager: suggest more swap space: 189 MB yet my swap usage is only half. Daemons which exhibit this behavior include the Internet junkbuster (since it forks on every http connection), samba, and secure shell. A sample traceback from internet junkbuster follows: bash$ gdb junkbuster junkbuster.core .... Core was generated by `junkbuster'. Program terminated with signal 11, Segmentation fault. Reading symbols from /usr/libexec/ld.so...done. Reading symbols from /usr/lib/aout/libc.so.3.1...done. #0 0x40e1 in block_url (http=0x26620, csp=0x26600) at filters.c:84 84 if((b->url->domain[0] == '\0') || (domaincmp(b-> url, url) == 0)) { (gdb) x b->url 0x23cc0 : 0x00000000 (gdb) (several times... until...) 0x23cfc : 0x00000000 (gdb) 0x23d00 : 0x4e524157 >Fix: The inetd "fix" simply appears to keep critical parts of inetd in memory at all times. This seems to prevent this problem from manifesting itself in inetd but still affects any other daemon which forks. So no fix is known for this problem. >Audit-Trail: >Unformatted: To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message