Ubuntu
audacity package

audacity crashed with SIGSEGV in memcpy() on WMA export

Bug #695648 reported by Benjamin Drung on 2010-12-30

This bug affects 1 person

Affects		Status	Importance	Assigned to	Milestone
	Audacity	Fix Released	Unknown	audacity-bugzilla #274
	audacity (Ubuntu)	Fix Released	Medium	Unassigned

Bug Description

Binary package hint: audacity

When exporting a file to WMA (version 2), audacity crashes at the end of the file. I can reproduce it with different sound files and on Ubuntu 10.10 (maverick) and Ubuntu 11.04 (natty).

You can use Cellule from Silence [1] as test case.

[1] http://www.jamendo.com/en/download/track/5339

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: audacity 1.3.12-8
ProcVersionSignature: Ubuntu 2.6.37-11.25-generic 2.6.37-rc7
Uname: Linux 2.6.37-11-generic x86_64
AlsaCards: Error: command ['cat', '/proc/asound/cards'] failed with exit code 1: cat: /proc/asound/cards: No such file or directory
Architecture: amd64
Date: Thu Dec 30 11:44:45 2010
ExecutablePath: /usr/bin/audacity
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Beta amd64 (20100318)
ProcCmdline: audacity
ProcEnviron:
SHELL=/bin/bash
PATH=(custom, user)
LC_MESSAGES=de_DE.utf8
LANG=de_DE.UTF-8
LANGUAGE=de_DE:de:en_GB:en
SegvAnalysis:
Segfault happened at: 0x7f78bc49abbe <memcpy+30>: movzwl (%rsi),%ecx
PC (0x7f78bc49abbe) ok
source "(%rsi)" (0x00000000) not located in a known VMA region (needed readable region)!
destination "%ecx" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: audacity
StacktraceTop:
memcpy () at ../sysdeps/x86_64/memcpy.S:78
put_buffer () from /usr/lib/libavformat.so.52
ff_put_wav_header () from /usr/lib/libavformat.so.52
?? () from /usr/lib/libavformat.so.52
?? () from /usr/lib/libavformat.so.52
Title: audacity crashed with SIGSEGV in memcpy()
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
XsessionErrors: (nautilus:1207): GConf-CRITICAL **: gconf_value_free: assertion `value != NULL' failed

Tags:

Related branches

lp:debian/audacity

Revision history for this message

Benjamin Drung (bdrung) wrote on 2010-12-30:

AudacityCfg.txt Edit (971 bytes, text/plain; charset="utf-8")
Dependencies.txt Edit (3.2 KiB, text/plain; charset="utf-8")
Disassembly.txt Edit (810 bytes, text/plain; charset="utf-8")
ProcMaps.txt Edit (68.8 KiB, text/plain; charset="utf-8")
ProcStatus.txt Edit (798 bytes, text/plain; charset="utf-8")
Registers.txt Edit (657 bytes, text/plain; charset="utf-8")
Stacktrace.txt Edit (6.2 KiB, text/plain; charset="utf-8")
ThreadStacktrace.txt Edit (10.2 KiB, text/plain; charset="utf-8")

Revision history for this message

Apport retracing service (apport) wrote on 2010-12-30:

StacktraceTop:
memcpy () at ../sysdeps/x86_64/memcpy.S:78
put_be24 (s=0x333f060, val=0)
?? ()

Revision history for this message

Apport retracing service (apport) wrote on 2010-12-30: Stacktrace.txt

Stacktrace.txt Edit (248 bytes, text/plain)

Revision history for this message

Apport retracing service (apport) wrote on 2010-12-30: ThreadStacktrace.txt

ThreadStacktrace.txt Edit (6.8 KiB, text/plain)

Changed in audacity (Ubuntu):
importance:	Undecided → Medium
tags:	removed: need-amd64-retrace

Benjamin Drung (bdrung) on 2010-12-30

visibility:

private → public

Revision history for this message

Benjamin Drung (bdrung) wrote on 2010-12-30: Re: audacity crashed with SIGSEGV in memcpy()

<bdrung> siretart: is this a ffmpeg bug?
<siretart> bdrung: I don't think so. the put_* functions are very basic, most probably audacity is trying to write to freed/invalid buffers

Revision history for this message

In Audacity Bugzilla #274, Benjamin Drung (bdrung) wrote on 2011-01-23:

When exporting a file to WMA (version 2), audacity crashes at the end of the
file. I can reproduce it with different sound files and on Ubuntu 10.10
(maverick) and Ubuntu 11.04 (natty).

You can use Cellule from Silence [1] as test case.

This is probably not a FFmpeg bug, but a bug in audacity. More information can
be found in Launchpad (including stacktrace): https://launchpad.net/bugs/695648

[1] http://www.jamendo.com/en/download/track/5339

Benjamin Drung (bdrung) on 2011-01-23

summary:	- audacity crashed with SIGSEGV in memcpy() + audacity crashed with SIGSEGV in memcpy() on WMA export
Changed in audacity (Ubuntu):
status:	New → Triaged

Revision history for this message

In Audacity Bugzilla #274, Gale (gale) wrote on 2011-02-06:

The crashes seem to occur with any 1.3.12 Beta/1.3.13 alpha build of Audacity
and any compatible version of FFmpeg. This seems to be an Audacity-on-Linux bug
to do with the standard export mechanism (using FFmpeg at the command line
either from a terminal and from Audacity's command line encoder works fine).

@Benjamin: We also have issues with incorrect AAC exports and AAC import
crashes (but this may be crashing of Audacity's own faulty AAC exports). It's
known that there is a problem with Audacity's interaction with the native
FFmpeg AAC . encoder. IIRC, LRN said this would be hard to fix. I believe the
older proprietary AAC encoder does not have this problem. Does the
Ubuntu-distributed FFmpeg use the native FFmpeg AAC encoder or the older one?
To use the older encoder I understand you have to compile FFmpeg with
--disable-encoder=aac.

Revision history for this message

In Audacity Bugzilla #274, Benjamin Drung (bdrung) wrote on 2011-02-07:

--disable-encoder=aac is only set on ia64. You can check that by looking at
debian/confflags in the FFmpeg source package or on git [1,2].

[1]
http://git.debian.org/?p=pkg-multimedia/ffmpeg.git;a=shortlog;h=refs/heads/ubuntu
[2]
http://git.debian.org/?p=pkg-multimedia/ffmpeg.git;a=blob;f=debian/confflags;h=da57f23aa2d3330b436121eb37a481b544928099;hb=012f3392c047e6917b9908b35b17623d0ec546c7

Revision history for this message

In Audacity Bugzilla #274, Gale (gale) wrote on 2011-02-07:

#10

(In reply to comment #2)
> --disable-encoder=aac is only set on ia64
Sorry if it is a silly question, but what does that mean in practice for a
basic Linux user who will not compile FFmpeg themseleves? Does it mean that a
user installing Ubuntu or Debian on ia64 will be using the old aac encoder,
otherwise the native ffmpeg aac encoder? In other words when I export AAC from
Audacity on a i386 machine pointing to the Ubuntu-distributed FFmpeg, I am
using the native FFmpeg encoder?

Revision history for this message

In Audacity Bugzilla #274, Benjamin Drung (bdrung) wrote on 2011-02-07:

#11

Yes, a user installing Ubuntu or Debian on ia64 will be using the old aac
encoder, otherwise the native ffmpeg aac encoder. Therefore most users (which
tend to either use i386 or amd64) will use the native FFmpeg encoder.

Revision history for this message

In Audacity Bugzilla #274, Leland-audacityteam (leland-audacityteam) wrote on 2011-03-08:

#12

Created an attachment (id=107)
A possible fix for the crash

Benjamin,

Can you try applying the attached patch and see if it fixes the crash?
Incidentally, the same crash happens on OSX when using a current FFmpeg
version.

Thanks,

Leland

Revision history for this message

In Audacity Bugzilla #274, Benjamin Drung (bdrung) wrote on 2011-03-08:

#13

After a two hours (yes, hours!) export of the test case (see Description), it
didn't crashed at the end. So yes, your patch fixes this bug.

Revision history for this message

In Audacity Bugzilla #274, Leland-audacityteam (leland-audacityteam) wrote on 2011-03-08:

#14

(In reply to comment #6)

Geez, how large was the file? Is this a case where you were talking about
exports taking forever?

Leland

Revision history for this message

In Audacity Bugzilla #274, Gale (gale) wrote on 2011-03-09:

#15

(In reply to comment #7)
> Geez, how large was the file? Is this a case where you were talking about
> exports taking forever?
It's only a 3 min 40 secs file. Which FFmpeg were you using, Benjamin? I'll try
Leland's patch later with the Ubuntu-distributed FFmpeg which is > 0.5, but
definitely there is no speed issue exporting WMA in the Ubuntu packaged
Audacity 1.3.12 - just a crash at the end.

There *is* an issue with slow AAC exports but as I understand it, only if you
use FFmpeg's native encoder. That does not play nicely with Audacity:
http://manual.audacityteam.org/m/index.php?title=FAQ:Installation_and_Plug-Ins#2009

but I don't have enough details to document it ATM.

Revision history for this message

In Audacity Bugzilla #274, Benjamin Drung (bdrung) wrote on 2011-03-09:

#16

I am using FFmpeg 4:0.6-2ubuntu6 shipped by Ubuntu 10.10 (maverick). I tested
the patch with the audacity Ubuntu package 1.3.12-14ubuntu1 (which includes the
patch from bug #233) and the WMA export took 11 seconds. All exports took
between 6 and 11 seconds and the resulting export were ok, except the AAC
export: The AAC export took around two minutes and the resulting file was too
small and couldn't be play-backed.

Then I tested trunk with the patch from bug #233: All exports were very slow
(MP3 > 1 min, FLAC > 2 min) and the resulting files contained silence. There
must be a regression, but that's unrelated to this bug report.

Revision history for this message

In Audacity Bugzilla #274, Benjamin Drung (bdrung) wrote on 2011-03-09:

#17

I open bug #311 dealing with the slow export.

Revision history for this message

Launchpad Janitor (janitor) wrote on 2011-03-09:

This bug was fixed in the package audacity - 1.3.12-15ubuntu1

---------------
audacity (1.3.12-15ubuntu1) natty; urgency=low

  * Merge from Debian unstable. Remaining changes:
    - Build against portSMF.
    - Build against libsbsms.

audacity (1.3.12-15) unstable; urgency=low

* Fix crash on WMA export (LP: #695648).
-- Benjamin Drung <email address hidden> Wed, 09 Mar 2011 12:29:45 +0100

Changed in audacity (Ubuntu):
status:	Triaged → Fix Released

Bug Watch Updater (bug-watch-updater) on 2011-03-12

Changed in audacity:
status:	Unknown → Confirmed

Revision history for this message

In Audacity Bugzilla #274, Gale (gale) wrote on 2011-03-12:

#18

On Ubuntu 10.10 using Ubuntu-distributed FFmpeg, this seems to be fixed by
applying the patch in bug 176 comment 10 which includes the patch attached
here.

Revision history for this message

In Audacity Bugzilla #274, Gale (gale) wrote on 2011-04-05:

#19

Fixed by patch for bug 176.

Bug Watch Updater (bug-watch-updater) on 2011-04-11

Changed in audacity:
status:	Confirmed → Fix Released

Report a bug

This report contains Public information

Everyone can see this information.

You are

Subscribing...

Edit bug mail

Other bug subscribers

Remote bug watches

audacity-bugzilla #274
[RESOLVED FIXED] Edit

Bug watches keep track of this bug in other bug trackers.

Ubuntuaudacity package

audacity crashed with SIGSEGV in memcpy() on WMA export

Bug Description

Related branches

Other bug subscribers

Bug attachments

Remote bug watches

Ubuntu
audacity package