[arch-general] [linux] ext4 data corruption bug

[Christian Hesse]

Dave Reisner <d at falconindy.com> on Wed, 2012/10/24 08:23:
> On Wed, Oct 24, 2012 at 02:00:01PM +0200, Christian Hesse wrote:
> > Hello everybody,
> > 
> > a thread has been started on lkml discussing a serious ext4 data
> > corruption bug in latest stable kernels. [0]
> > 
> > Looks like the root cause is not really clear so far. Reverting the
> > commit in question should fix the problem though.
> > 
> > [0] https://lkml.org/lkml/2012/10/23/690
>
> Why would you suggest a revert and that "the root cause is not really
> clear" when tytso has already proposed a fix along with a detailed
> explanation of why the bug occurs?

Tytso writes about Eric reviewing his patch:

> Until then, it should also be fine to just revert that commit on the
> other stable kernels.

Though later in the thread Tytso writes:

> P.S.  This is a list of all of the commits between v3.6.1 and v3.6.2
> (there were no ext4-related changes between v3.6.2 and v3.6.3), and a
> quick analysis of the patch.  The last commit, 14b4ed2, is the only
> one that I could see as potentially being problematic, which is why
> I've been pushing so hard on this one even though my original analysis
> doesn't seem to be correct, and Eric and I can't see how the change in
> 14b4ed2 could be causing the fs corruption.

So it looks like nobody really knows what to do best...
-- 
main(a){char*c=/*    Schoene Gruesse                         */"B?IJj;MEH"
"CX:;",b;for(a/*    Chris           get my mail address:    */=0;b=c[a++];)
putchar(b-1/(/*               gcc -o sig sig.c && ./sig    */b/42*2-3)*42);}