Bug 127131
Summary: | Kernel bug with IPv6 SSM multicast | ||||||
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Product: | [Fedora] Fedora | Reporter: | Nick Lamb <njl> | ||||
Component: | kernel | Assignee: | David Miller <davem> | ||||
Status: | CLOSED CURRENTRELEASE | QA Contact: | Brian Brock <bbrock> | ||||
Severity: | high | Docs Contact: | |||||
Priority: | medium | ||||||
Version: | 2 | ||||||
Target Milestone: | --- | ||||||
Target Release: | --- | ||||||
Hardware: | i386 | ||||||
OS: | Linux | ||||||
URL: | http://www.atm.tut.fi/mad/ | ||||||
Whiteboard: | |||||||
Fixed In Version: | Doc Type: | Bug Fix | |||||
Doc Text: | Story Points: | --- | |||||
Clone Of: | Environment: | ||||||
Last Closed: | 2004-08-04 14:46:21 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: | |||||||
Attachments: |
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Description
Nick Lamb
2004-07-02 13:16:39 UTC
Created attachment 101596 [details]
Crashlog from kernel 2.6.6-1.435.2.3
This is identical to the crash I reported in bug 126021 since the original bug reported there is (apparently) fixed, but this persists. This is definitely fragmentation related. FLUTE works by sending IPv6 UDP packets to a multicast address. It appears that MAD-FLUTE v1.0 sends packets which get fragmented, and that's when the kernel bug is triggered. Limiting the packet size to e.g. 1000 bytes with -l:1000 sidesteps the crash on 2.6.6-1.435.2.3, this is a sufficient workaround for my immediate purpose, but of course that doesn't fix the bug. Is it worth me trying to narrow down the problem, perhaps to a short code segment that can be tested anywhere? I'd be more encouraged if I'd seen any kind of response to this bug in the 11 days since it was filed. Well, part of this is that I've been away at a networking conference trip all last week. :-) Yes, please try to put together a small test case. When it requires a larger or non-trivial program to be setup, such as flute, it makes it more difficult to work on the bug. Newly released kernel 2.6.7-1.494.2.2 seems to eliminate the kernel oops or crash/hang seen previously. Thanks. I've been too busy fighting very different but equally annoying bugs in FreeBSD to create a testcase, sorry. The fragmentation itself still happens for default settings on flute, but I will get feedback from core flute developers before deciding whether that's a Linux bug. Presumably you'd prefer to CLOSE this bug as RAWHIDE or whatever the modern equivalent is, and if the frags do turn out to be a kernel bug either we'd re-open it with a lower severity or file a new bug (your choice). |