Re: [PATCH] ceph: Fix an Oops in error handling

Ilya Dryomov
2021-02-02T12:35:35Z

On Tue, Feb 2, 2021 at 6:47 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> The "req" pointer is an error pointer and not NULL so this check needs
> to be fixed.
>
> Fixes: 1cf7fdf52d5a ("ceph: convert readpage to fscache read helper")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> fs/ceph/addr.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
> index 5eec6f66fe52..fb0238a4d34f 100644
> --- a/fs/ceph/addr.c
> +++ b/fs/ceph/addr.c
> @@ -273,7 +273,7 @@ static void ceph_netfs_issue_op(struct netfs_read_subrequest *subreq)
> if (err)
> iput(inode);
> out:
> - if (req)
> + if (!IS_ERR_OR_NULL(req))
> ceph_osdc_put_request(req);
> if (err)
> netfs_subreq_terminated(subreq, err);

Hi Dan,

I think a better fix would be to set req to NULL in the offending
IS_ERR branch since ceph_osdc_new_request() never returns NULL or
use two separate goto labels.

While at it, the initialization of req and the check on req before
calling ceph_osdc_put_request() are redundant.

Thanks,

Ilya