Bug 31702 - DAVFS: segfault
Summary: DAVFS: segfault
Status: RESOLVED FIXED
Alias: None
Product: Mageia
Classification: Unclassified
Component: RPM Packages (show other bugs)
Version: Cauldron
Hardware: All Linux
Priority: Normal minor
Target Milestone: ---
Assignee: QA Team
QA Contact:
URL:
Whiteboard: MGA9-64-OK
Keywords: IN_ERRATA9
Depends on:
Blocks:
 
Reported: 2023-03-20 12:09 CET by Marc Krämer
Modified: 2023-05-19 01:30 CEST (History)
3 users (show)

See Also:
Source RPM: davfs2-1.7.0-1.mga9.src.rpm
CVE:
Status comment:


Attachments

Description Marc Krämer 2023-03-20 12:09:19 CET
after mount and accessing the davfs filesystem I get this error (enabled debug output of davfs)

Mär 20 12:03:50 localhost kernel: Code: 01 48 89 fb f7 dd 66 81 e5 83 73 48 83 ec 18 64 48 8b 04 25 28 00 00 00 48 89 44 24 08 31 c0 89 e8 80 cc 40 83 e6 02>
Mär 20 12:03:50 localhost kernel: mount.davfs[3359]: segfault at 0 ip 00007fae26b3efa8 sp 00007ffe41c89080 error 4 in libneon.so.27.4.2[7fae26b36000+19000] >
Mär 20 12:03:50 localhost mount.davfs[3359]:   p 0x10e4260, admin_du.sql-nNYvlP
Mär 20 12:03:50 localhost mount.davfs[3359]: FUSE_LOOKUP:
Mär 20 12:03:50 localhost mount.davfs[3359]: SELECT: 1
Mär 20 12:03:50 localhost mount.davfs[3359]: RET: Erfolg
Mär 20 12:03:50 localhost mount.davfs[3359]:   pid 0, fd 6
Mär 20 12:03:50 localhost mount.davfs[3359]:   n 0x10e4260, f 0304000


uname -a
Linux localhost 6.2.7-desktop-1.mga9 #1 SMP PREEMPT_DYNAMIC Sun Mar 19 11:34:31 UTC 2023 x86_64 GNU/Linux

this is pretty essential for my daily work - and I'm pretty sure this has worked last week.
Comment 1 Marc Krämer 2023-03-20 12:25:07 CET
after cleaning my local cache
rm -f /home/marc/.davfs2/cache/dest/*
it works again.

Looks like if run into this bug:
https://savannah.nongnu.org/bugs/?63771
Marc Krämer 2023-03-20 12:25:15 CET

See Also: (none) => https://savannah.nongnu.org/bugs/?63771

Marc Krämer 2023-03-20 12:29:25 CET

See Also: (none) => https://savannah.nongnu.org/bugs/?63364

Comment 2 Lewis Smith 2023-03-20 21:37:56 CET
Please confirm the package & version; as in the SRPM field?

(In reply to Marc Krämer from comment #1)
> Looks like if run into this bug:
> https://savannah.nongnu.org/bugs/?63771
This refers specifically to  "nginx dav module and special chars". Did you have either of these?
"I tried using this simple script as webdav server: https://gist.github.com/mickael-kerjean/f2f034bdad5e077edcbfdff649d52d68
And the above steps won't make any crashes, the file content can be normally shown."
No other action on the bug.

https://savannah.nongnu.org/bugs/?63364
"davfs2 1.7.0 mounts segfault when accessed with dolphin"
Is this your case? No action on the bug.

(In reply to Marc Krämer from comment #0)
> this is pretty essential for my daily work - and I'm pretty sure this has
> worked last week.
I can see no Cauldron activity on this since:
Nov 19 2022 : update to 1.7.0
So can you look for something else that has changed recently? Can you relate it to a kernel update?

Source RPM: (none) => davfs2-1.7.0-1.mga9.src.rpm
CC: (none) => lewyssmith

Comment 3 Marc Krämer 2023-03-21 10:06:39 CET
I should have lowered the priority after I found the reason.

It looks like davfs has some bugs handling special files. In my case these files were not on the server, but on the client in the lost+found directory. Not sure if netbeans really tried to access them and caused the crash. But I was unable to remove them while davfs is mounted - I had to remove them from the cache folder when davfs is unmounted. Afterwards it works like ever.

Severity: major => minor

Comment 4 Lewis Smith 2023-03-21 10:15:49 CET
Thanks for the detective work and good result. Can you say for others what you mean by 'special files'? How did you identify them?

Can we - you - close the bug?

Noted for M9 Errata.

Keywords: (none) => FOR_ERRATA9

Comment 5 Marc Krämer 2023-03-21 11:04:12 CET
In lost+found a file is saved, when the remote host does not accept the file (e.g. down, or write protected, ...) so lost+found fills over the time.
The files saved here are named: originalfile.txt-HASH so besides the "-" there is nothing special about it. An example is:
manage.tmpl-2m83k5
manage.tmpl-3uA4Kk

But it looks like the dir-index of "lost+found" causes this problem and I guess it is the "+" sign:

cd lost+found/
[marc@localhost lost+found]$ ls
ls: cannot access 'dir-lost+found-xhbokx': Software caused connection abort
ls: cannot access 'dir-lost+found-rLn3pO': Transport endpoint is not connected
....

Status: NEW => UPSTREAM

Comment 6 Lewis Smith 2023-03-25 12:20:35 CET
Can we assign this to pkg-bugs? Nothing that Bugsquad can do with it.
Comment 7 Marc Krämer 2023-03-26 12:48:39 CEST
Sure, we need an upstream update to get this fixed. But it is the bugreport we need, to get an updated version into stable mga9 :)
Morgan Leijström 2023-03-26 15:30:52 CEST

CC: (none) => fri
Assignee: bugsquad => pkg-bugs

Comment 8 Marc Krämer 2023-03-31 12:20:14 CEST
happend again - files in lost+found of davfs seems to cause this error, or a broken lookup file which determines which cached file belongs in lost+found and which is a regular file
Lewis Smith 2023-04-16 09:45:12 CEST

Keywords: FOR_ERRATA9 => IN_ERRATA9

Comment 9 Marc Krämer 2023-05-17 19:16:30 CEST
Added a fix, restores speed and does not crash anymore.

Update in core/updates_testing
davfs2-1.7.0-2.mga9

SRPM:
davfs2-1.7.0-2.mga9.src.rpm

Assignee: pkg-bugs => qa-bugs

Marc Krämer 2023-05-17 19:16:46 CEST

Status: UPSTREAM => ASSIGNED

Comment 10 Lewis Smith 2023-05-17 20:47:30 CEST
Great work, Marc.
Since you are the only complainant so far, if this works for you - can we call it MGA9-64-OK ? I doubt whether QA will be able to test the fault in question, nor indeed the application; only that the update happens OK.
Marc Krämer 2023-05-17 20:59:40 CEST

Whiteboard: (none) => MGA9-64-OK

Comment 11 Marc Krämer 2023-05-17 21:00:10 CEST
Sure, we can.
Comment 12 Dave Hodgins 2023-05-17 22:06:42 CEST
This is still cauldron in version freeze, not release freeze.

Request a freeze push in the dev ml.

CC: (none) => davidwhodgins

Comment 13 Marc Krämer 2023-05-19 01:30:29 CEST
moved

Resolution: (none) => FIXED
Status: ASSIGNED => RESOLVED


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