On Wed, Jun 15, 2016 at 10:02:41AM +1000, Dave Chinner wrote: > On Mon, Jun 13, 2016 at 11:57:53PM +0200, Thomas D. wrote: > > Hi, > > > > can anybody confirm if there's something broken with the latest XFS > > change set which is now applied on all stable kernels? > > > > I found https://forums.grsecurity.net/viewtopic.php?t=4489&p=16355 and > > grsec changelog says > > > > > commit 1f621dc42acbabb71bd69f6ba606cee56e7ad3bc > > > Author: Brad Spengler <spender@xxxxxxxxxxxxxx> > > > Date: Sat Jun 11 08:14:32 2016 -0400 > > > > > > Fix Greg KH's broken XFS backport, caused a benign case to be detected > > > as disk corruption > > > Problem was due to a tree-wide conversion of error codes to their negative > > > counterparts, which would likely never be backported to older kernels, but > > > the backports didn't account for the change > > > > > > fs/xfs/xfs_inode.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > Yes, the backport is busted, and needs this fix. The error sign > change occurred in 3.17. xfstests would have picked up this > regression in a couple of minutes, so I'm guessing that none of > these stable releases have had any significant regression testing > done.... > > > This is the change grsec applied: > > > > > diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c > > > index fb8579d..af807d8 100644 > > > --- a/fs/xfs/xfs_inode.c > > > +++ b/fs/xfs/xfs_inode.c > > > @@ -3098,7 +3111,7 @@ xfs_iflush( > > > */ > > > error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK, > > > 0); > > > - if (error == -EAGAIN) { > > > + if (error == EAGAIN) { > > > xfs_ifunlock(ip); > > > return error; > > > } > > Yes, that is the fix that is needed. Thank you for reporting it to > us. > > Mr Spender: it would be appreciated if you reported stable kernel > regressions to the relevant upstream maintainers so they can be > fixed quickly for everyone, rather than having one of your users > decide it needs to be reported. > > Stable kernel maintainers: the above error sign change is needed for > stable kernels 3.16 and earlier, as a matter of critical importance. > And as a further matter of critical importance: in future, please > take the time to regression test the changes you backport. > > > The bad commit according to grsec's statement is > > > > > From b1438f477934f5a4d5a44df26f3079a7575d5946 Mon Sep 17 00:00:00 2001 > > > From: Dave Chinner <dchinner@xxxxxxxxxx> > > > Date: Wed, 18 May 2016 13:53:42 +1000 > > > Subject: [PATCH] xfs: xfs_iflush_cluster fails to abort on error > > > > Would be nice to get some clarification. > > There's nothing wrong with that commit in the upstream kernel, > it's the backport that has a bug in it because it failed to take > into account changes outside the context of the upstream commit that > the older kernels don't have. Thanks for letting me know about this. As the patch was tagged with 3.10+, I assumed that it was safe to be merged to those older kernels, otherwise I would never have done so. We do have ways to mark external things like this for stable patches, it's a great help when doing backports. thanks, greg k-h _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
