Bug 501604
| Summary: | xinetd can hang while processing unknown signal | ||||||
|---|---|---|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 5 | Reporter: | Bryan Mason <bmason> | ||||
| Component: | xinetd | Assignee: | Vojtech Vitek <vvitek> | ||||
| Status: | CLOSED ERRATA | QA Contact: | qe-baseos-daemons | ||||
| Severity: | medium | Docs Contact: | |||||
| Priority: | low | ||||||
| Version: | 5.3 | CC: | azelinka, cww, hripps, mcermak, ovasik | ||||
| Target Milestone: | rc | ||||||
| Target Release: | --- | ||||||
| Hardware: | All | ||||||
| OS: | Linux | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | |||||||
| : | 694820 697785 (view as bug list) | Environment: | |||||
| Last Closed: | 2011-05-25 08:39:21 UTC | Type: | --- | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
| Bug Depends On: | |||||||
| Bug Blocks: | 502912, 590060, 694820, 697785 | ||||||
| Attachments: |
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This request was evaluated by Red Hat Product Management for inclusion, but this component is not scheduled to be updated in the current Red Hat Enterprise Linux release. If you would like this request to be reviewed for the next minor release, ask your support representative to set the next rhel-x.y flag to "?". An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2011-0827.html |
Created attachment 344727 [details] Patch proposed by Siddhesh Poyarekar Description of problem: If a signal is sent to xinetd when xinetd is in the middle of logging to syslog, xinetd could end up hung. Version-Release number of selected component (if applicable): xinetd-2.3.14-10 How reproducible: Depends on timing, but can be reproduced reliably once the timing is discovered. Steps to Reproduce: 1. kill -SIGHUP `pgrep xinetd` && sleep 0.001 && kill -SIGCONT `pgrep xinetd` 2. adjust the value of sleep until xinetd hangs. Values vary from 0.001 to 0.2. Actual results: xinetd hangs Expected results: no hang Additional info: The core issue seems to be the msg() call within one of the signal handlers. When signaled when within a msg() call the earlier syslog_write() has already acquired a lock to write the previous message to syslog. The current call then simply waits forever trying to acquire that lock. Proposed patch attached. Patch has been proposed upstream as well. Awaiting feedback from upstream maintainer.