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Subject: Re: [PATCH] ceph: fix memory leak in mount error path when using
 test_dummy_encryption
To:     =?UTF-8?Q?Lu=c3=ads_Henriques?= <lhenriques@suse.de>,
        Ilya Dryomov <idryomov@gmail.com>,
        Jeff Layton <jlayton@kernel.org>
Cc:     ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20221103153619.11068-1-lhenriques@suse.de>
From:   Xiubo Li <xiubli@redhat.com>
Message-ID: <700018a6-aff7-6e7a-98df-2fc8cca39acb@redhat.com>
Date:   Mon, 7 Nov 2022 15:47:23 +0800
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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@suse.de>
> ---
>   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:
>