Re: [PATCH 2/2] fs/ceph/mds_client: fix cred leak in ceph_mds_check_access()

[Xiubo Li <xiubli@redhat.com>]

On 11/23/24 15:21, Max Kellermann wrote:
> get_current_cred() increments the reference counter, but the
> put_cred() call was missing.
>
> Fixes: 596afb0b8933 ("ceph: add ceph_mds_check_access() helper")
> Cc: stable@vger.kernel.org
> Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
> ---
>   fs/ceph/mds_client.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
> index e8a5994de8b6..35d83c8c2874 100644
> --- a/fs/ceph/mds_client.c
> +++ b/fs/ceph/mds_client.c
> @@ -5742,6 +5742,7 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
>   
>   		err = ceph_mds_auth_match(mdsc, s, cred, tpath);
>   		if (err < 0) {
> +			put_cred(cred);
>   			return err;
>   		} else if (err > 0) {
>   			/* always follow the last auth caps' permision */
> @@ -5757,6 +5758,8 @@ int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath, int mask)
>   		}
>   	}
>   
> +	put_cred(cred);
> +
>   	doutc(cl, "root_squash_perms %d, rw_perms_s %p\n", root_squash_perms,
>   	      rw_perms_s);
>   	if (root_squash_perms && rw_perms_s == NULL) {

Good catch.

Reviewed-by: Xiubo Li <xiubli@redhat.com>