Re: [PATCH] gfs2: Fix error path kobject memory leak

From: Tobin C. Harding
Date: Mon May 13 2019 - 17:42:59 EST


On Mon, May 13, 2019 at 06:41:23PM +0200, Andreas Gruenbacher wrote:
> On Mon, 13 May 2019 at 12:40, Tobin C. Harding <me@xxxxxxxx> wrote:
> >
> > On Mon, May 13, 2019 at 09:14:05AM +0200, Greg Kroah-Hartman wrote:
> > > On Mon, May 13, 2019 at 01:32:13PM +1000, Tobin C. Harding wrote:
> > > > If a call to kobject_init_and_add() fails we must call kobject_put()
> > > > otherwise we leak memory.
> > > >
> > > > Function always calls kobject_init_and_add() which always calls
> > > > kobject_init().
> > > >
> > > > It is safe to leave object destruction up to the kobject release
> > > > function and never free it manually.
> > > >
> > > > Remove call to kfree() and always call kobject_put() in the error path.
> > > >
> > > > Signed-off-by: Tobin C. Harding <tobin@xxxxxxxxxx>
> > > > ---
> > > >
> > > > Is it ok to send patches during the merge window?
> > > >
> > > > Applies on top of Linus' mainline tag: v5.1
> > > >
> > > > Happy to rebase if there are conflicts.
> > > >
> > > > thanks,
> > > > Tobin.
> > > >
> > > > fs/gfs2/sys.c | 7 +------
> > > > 1 file changed, 1 insertion(+), 6 deletions(-)
> > > >
> > > > diff --git a/fs/gfs2/sys.c b/fs/gfs2/sys.c
> > > > index 1787d295834e..98586b139386 100644
> > > > --- a/fs/gfs2/sys.c
> > > > +++ b/fs/gfs2/sys.c
> > > > @@ -661,8 +661,6 @@ int gfs2_sys_fs_add(struct gfs2_sbd *sdp)
> > > > if (error)
> > > > goto fail_reg;
> > > >
> > > > - sysfs_frees_sdp = 1; /* Freeing sdp is now done by sysfs calling
> > > > - function gfs2_sbd_release. */
> > >
> > > You should also delete this variable at the top of the function, as it
> > > is now only set once there and never used.
> >
> > Thanks, I should have gotten a compiler warning for that. I was feeling
> > so confident with my builds this morning ... pays not to get too cocky
> > I suppose.
> >
> > > With that:
> > >
> > > Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> >
> > Thanks, will re-spin.
>
> Don't bother, I'll fix that up.

Thanks man!