Re: [PATCH v2] ceph: fix memory leak in mount error path when using test_dummy_encryption

[Xiubo Li <xiubli@redhat.com>]

On 09/11/2022 18:38, Luís Henriques wrote:
> On Wed, Nov 09, 2022 at 05:57:41PM +0800, Xiubo Li wrote:
>> Hi Luis,
>>
>> Please check https://github.com/ceph/ceph-client/commit/205efda80b6759a741dde209a7158a5bbf044d23#diff-eb62c69f842ed95a7d047262a62946b07eda52f2ea49ae33c39ea13754dfc291.
> Ugh! That's quite confusing :-)
>
> I did a 'git fetch' and looked into commit 205efda80b67 ("ceph: implement
> -o test_dummy_encryption mount option") instead, and compared it with it's
> version in the wip-fscrypt branch.  It looks good to me: the only
> difference I see is my fix (adding the 'ceph_fscrypt_free_dummy_policy'
> call to 'ceph_real_mount').  Thanks!

I will update the wip-fscrypt branch later.

Thanks!


> Cheers,
> --
> Luís
>
>> Currently I only applied it into the 'testing' branch.
>>
>> Thanks!
>>
>> - Xiubo
>>
>>
>> On 09/11/2022 17:33, Luís Henriques wrote:
>>> On Wed, Nov 09, 2022 at 11:08:49AM +0800, Xiubo Li wrote:
>>>> On 08/11/2022 22:34, 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>
>>>>> ---
>>>>> * Changes since v1:
>>>>>
>>>>> As suggested by Xiubo, moved fscrypt free from ceph_get_tree() to
>>>>> ceph_real_mount().
>>>>>
>>>>> (Also used 'git format-patch' with '--base' so that the bots know what to
>>>>> (not) do with this patch.)
>>>>>
>>>>>     fs/ceph/super.c | 1 +
>>>>>     1 file changed, 1 insertion(+)
>>>>>
>>>>> diff --git a/fs/ceph/super.c b/fs/ceph/super.c
>>>>> index 2224d44d21c0..f10a076f47e5 100644
>>>>> --- a/fs/ceph/super.c
>>>>> +++ b/fs/ceph/super.c
>>>>> @@ -1196,6 +1196,7 @@ static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
>>>>>     out:
>>>>>     	mutex_unlock(&fsc->client->mount_mutex);
>>>>> +	ceph_fscrypt_free_dummy_policy(fsc);
>>>>>     	return ERR_PTR(err);
>>>>>     }
>>>>>
>>>>> base-commit: 8b9ee21dfceadd4cc35a87bbe7f0ad547cffa1be
>>>>> prerequisite-patch-id: 34ba9e6b37b68668d261ddbda7858ee6f83c82fa
>>>>> prerequisite-patch-id: 87f1b323c29ab8d0a6d012d30fdc39bc49179624
>>>>> prerequisite-patch-id: c94f448ef026375b10748457a3aa46070aa7046e
>>>>>
>>>> LGTM.
>>>>
>>>> Thanks Luis.
>>>>
>>>> Could I fold this into the previous commit ?
>>> Yes, sure.  I'm fine with that.
>>>
>>> Cheers,
>>> --
>>> Luís
>>>