730656 - Only one user on system can stream html5/webm with linux

Status: RESOLVED DUPLICATE of bug 612246

(Core :: Audio/Video, defect)

Description

[Chris Vine]

User Agent: Mozilla/5.0 (X11; Linux i686; rv:10.0.2) Gecko/20100101 Firefox/10.0.2
Build ID: 20120220143356

Steps to reproduce:

Visit a page with an html5 video tag, such as http://camendesign.com/code/video_for_everybody/test.html using firefox for linux.  If you are not the first user to have streamed video on the particular computer concerned, the video will not stream.  The cause is set out below.


Actual results:

If you are not the first user to have streamed video on a particular computer using firefox (and possibly any other mozilla product), html5/webm video will not stream.

The cause is the defective use of a caching directory in /tmp.  Firefox uses a /tmp/mozilla-media-cache sub-directory to store its online streaming. This sub-directory appears to be created when the first user streams using firefox (or presumably some other mozilla product), and is owned by that first user with 0700 permissions.  As a result, only that first user is able to access the cache directory and so stream.

The proper approach is have the caching sub-directory in each users' home directory, or if it is to stay in /tmp, to give the sub-directory a name which has the particular user's name prepended or postpended.


Expected results:

More than one user on a particular computer should be able to stream html5/webm video.

Comment 1

[Chris Vine]

Attachment: fix for unix-like systems

Here is a fix which works for me on linux and will presumably work with other unix-like systems.

It does not affect the code in nsMediaCacheRemover.cpp which is windows specific and is only compiled in if XP_WIN is defined.  I have no idea whether there is a similar problem on windows (whether in terms of failure to play or security/privacy from shared data), as I do not use that OS.

Comment 2

[Matthias Versen [:Matti]]

Comment on attachment 600757 [details] [diff] [review]
fix for unix-like systems

You have to request review from someone...

Comment 3

[Jo Hermans]

this is a duplicate of bug 612246, which a better (cross-platform) patch

Comment 4

[Chris Vine]

Comments #2 and #3

"You have to request review from someone" ... "this is a duplicate of bug 612246, which a better (cross-platform) patch"

I am amazed that a user-impacting bug such as this, first reported in 2010, has been left lying so long in any code base which wants to be taken seriously.  You would think that some project maintainer would want to fix this on a bug report, without someone asking for a code review as well as filing a bug.

I am sure there are other ways of dealing with this (I don't know the mozilla code base) but that is hardly the point.  At the moment there is no way of more than one user account using html5 with firefox until someone or something clears the /tmp directory.  What will happen in consequence is that people affected will scratch their heads, shrug, and use a different browser.  (I gather the mozilla foundation are to carry out a survey to find out why that is happening; this might be included as an input.)

Comment 5

[Matthias Versen [:Matti]]

Comment on attachment 600757 [details] [diff] [review]
fix for unix-like systems

removing review request and marking as dupe