Bug 205165

Summary:	[ip6] [panic] Multiple race conditions in the V6 list manipulation
Product:	Base System	Reporter:	Jason Wolfe <j>
Component:	kern	Assignee:	Sean Bruno <sbruno>
Status:	Closed FIXED
Severity:	Affects Some People	CC:	j, kbowling, sbruno
Priority:	---	Keywords:	crash, needs-qa, patch
Version:	10.2-STABLE	Flags:	koobs: mfc-stable10? koobs: mfc-stable9?
Hardware:	amd64
OS:	Any
URL:	https://reviews.freebsd.org/D2254

Description Jason Wolfe 2015-12-09 19:12:28 UTC

Creating this ticket to track conversation that has gone on in the mailing list related to race conditions in the v6 stack.  Notably for us when processing concurrent router advertisement packets and modifying the route lists.

https://lists.freebsd.org/pipermail/freebsd-net/2015-December/044024.html

It appears these issues have been known about for a few years, and some work has been done on them.  We are testing these 2 and are seeing good initial results.

https://reviews.freebsd.org/D2254
https://people.freebsd.org/~markj/patches/ndp-locking.diff

Comment 1 Jason Wolfe 2015-12-09 19:24:14 UTC

https://lists.freebsd.org/pipermail/freebsd-net/2013-February/034682.html was another conversation that happened a few years back which I believe spawned the above patches.

Comment 2 Sean Bruno freebsd_committer

2015-12-10 18:33:59 UTC

I'm keeping an eye on this for work, so I'll be the assignee.

Comment 3 Sean Bruno freebsd_committer

2016-05-24 14:16:29 UTC

Another commit for this ticket:

https://svnweb.freebsd.org/base?view=revision&revision=300536

Comment 4 Jason Wolfe 2017-06-20 18:50:35 UTC

So the crashes reported in this ticket have been resolved in HEAD, but they missed 11.0-RELEASE. I know markj had a few more places he wanted to address (D2254), but the cores noted in this ticket have not been seen on 12.

Comment 5 Sean Bruno freebsd_committer

2018-05-14 19:31:55 UTC

This has been resolved in newer releases of FreeBSD.