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

From: Greg Kroah-Hartman
Date: Mon May 13 2019 - 03:15:38 EST


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.

With that:

Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>