Re: fanotify use after free.

From: Jiri Kosina
Date: Thu Jan 23 2014 - 10:07:54 EST


On Thu, 23 Jan 2014, Jan Kara wrote:

> > > > But refcounting seems like an overkill for this - there is exactly one
> > > > fanotify_response_event structure iff it is a permission event. So
> > > > something like the (completely untested) attached patch should fix the
> > > > problem. But I agree it's a bit ugly so we might want something different.
> > > > I'll try to think about something better tomorrow.
> > >
> > > Ok, In the meantime, Dave, can you verify whether this hacky patch
> > > fixes your problem?
> >
> > I reported the same slab corruption yesterday as well here:
> >
> > https://lkml.org/lkml/2014/1/22/173
> >
> > With the patch applied, I am still seeing the slab corruption, preceeded
> > by GPF (which is not there without the patch) in
> > lockref_put_or_lock(&dentry->d_lockref) in dput():
> Hmm, OK. Can you please send me your .config? I'll try to reproduce this
> myself.

Attached.

The userspace is systemd-based.

--
Jiri Kosina
SUSE Labs

Attachment: config.gz
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