Re: [PATCH] ceph: fix memory leak in mount error path when using test_dummy_encryption

[Xiubo Li]

On 03/11/2022 23:36, Luís Henriques wrote:
> Because ceph_init_fs_context() will never be invoced in case we get a
> mount error, destroy_mount_options() won't be releasing fscrypt resources
> with fscrypt_free_dummy_policy().  This will result in a memory leak.  Add
> an invocation to this function in the mount error path.
>
> Signed-off-by: Luís Henriques <lhenriques@xxxxxxx>
> ---
>   fs/ceph/super.c | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/fs/ceph/super.c b/fs/ceph/super.c
> index 2224d44d21c0..6b9fd04b25cd 100644
> --- a/fs/ceph/super.c
> +++ b/fs/ceph/super.c
> @@ -1362,6 +1362,7 @@ static int ceph_get_tree(struct fs_context *fc)
>   
>   	ceph_mdsc_close_sessions(fsc->mdsc);
>   	deactivate_locked_super(sb);
> +	fscrypt_free_dummy_policy(&fsc->fsc_dummy_enc_policy);

Hi Luis,

BTW, any reason the following code won't be triggered ?

deactivate_locked_super(sb);

  --> fs->kill_sb(s);

        --> ceph_kill_sb()

              --> kill_anon_super()

                    --> generic_shutdown_super()

                          --> sop->put_super()

                                --> ceph_put_super()

                                      --> ceph_fscrypt_free_dummy_policy()

                                           --> fscrypt_free_dummy_policy(

Thanks!

- Xiubo


>   	goto out_final;
>   
>   out: