Bug 929098
Summary: | CPG: Corosync can duplicate and/or lost messages - Local IPC | ||
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Product: | Red Hat Enterprise Linux 6 | Reporter: | Libor Miksik <lmiksik> |
Component: | corosync | Assignee: | Jan Friesse <jfriesse> |
Status: | CLOSED ERRATA | QA Contact: | Cluster QE <mspqa-list> |
Severity: | urgent | Docs Contact: | |
Priority: | urgent | ||
Version: | 6.4 | CC: | abienven, bmarson, cluster-maint, jfriesse, jkortus, mjuricek, perfbz, pm-eus, sdake |
Target Milestone: | rc | Keywords: | ZStream |
Target Release: | --- | ||
Hardware: | All | ||
OS: | All | ||
Whiteboard: | |||
Fixed In Version: | corosync-1.4.1-4.el6_2.5 | Doc Type: | Bug Fix |
Doc Text: |
When running applications which used the Corosync IPC library, some messages in the dispatch() function were lost or duplicated. This update properly checks the return values of the dispatch_put() function, returns the correct remaining bytes in the IPC ring buffer, and ensures that the IPC client is correctly informed about the real number of messages in the ring buffer. Now, messages in the dispatch() function are no longer lost or duplicated.
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Story Points: | --- |
Clone Of: | Environment: | ||
Last Closed: | 2013-04-09 10:29:36 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: | 922671 | ||
Bug Blocks: | |||
Attachments: |
Description
Libor Miksik
2013-03-29 09:18:13 UTC
Created attachment 718032 [details] 6.2.z-bz929098-1-Put-handle-to-hdb-in-dispatch-on-unknown-message Put handle to hdb in dispatch on unknown message When we receive unknown dispatch type, we should put handle to hdb, because it was correctly obtained. This problem is only cfg and confdb libraries, cpg, evs, quorum, ... are not affected and works correctly. Signed-off-by: Jan Friesse <jfriesse> Reviewed-by: Fabio M. Di Nitto <fdinitto> Created attachment 718033 [details] 6.2.z-bz929098-2-Properly-check-result-of-coroipcc_dispatch_put Properly check result of coroipcc_dispatch_put When result of coroipcc_dispatch_put it can happen, that one message is delivered to user application multiple times. Signed-off-by: Jan Friesse <jfriesse> Reviewed-by: Fabio M. Di Nitto <fdinitto> Created attachment 718034 [details] 6.2.z-bz929098-3-coroipcs-Ensure-rb-data-are-not-overwritten coroipcs: Ensure rb data are not overwritten With introduce of rb alignment (55600762), it's not enough to subtract one from number of free bytes, but also alignment must be taken to account. Easiest solution is to subtract 9 bytes. Signed-off-by: Jan Friesse <jfriesse> Reviewed-by: Steven Dake <sdake> Created attachment 718035 [details] 6.2.z-bz929098-4-Properly-lock-pending_semops Properly lock pending_semops pending_semops variable can be changed in two threads. One is actual IPC connection and second is coropoll. It's really scholar example of race (one thread doing i++, second doing i--). If socket is full, it can happen that IPC will increase value and coropoll will decrease, resulting in unpredictable value. This means, that client IPC can be informed about more messages then really available, resulting in reading of garbage messages in library dispatch function. Solution is to properly lock variable. Signed-off-by: Jan Friesse <jfriesse> Reviewed-by: Fabio M. Di Nitto <fdinitto> Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHBA-2013-0724.html |