[PATCH] nbd: don't leak nbd_config

[PATCH] nbd: don't leak nbd_config

[Ilya Dryomov]

nbd_config is allocated in nbd_alloc_config(), but never freed.

Fixes: 5ea8d10802ec ("nbd: separate out the config information")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 drivers/block/nbd.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 9a7bb2c29447..882fb9efbab1 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -940,6 +940,7 @@ static int nbd_reconnect_socket(struct nbd_device *nbd, unsigned long arg)
 /* Reset all properties of an NBD device */
 static void nbd_reset(struct nbd_device *nbd)
 {
+	kfree(nbd->config);
 	nbd->config = NULL;
 	nbd->tag_set.timeout = 0;
 	queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue);
-- 
2.4.3

Re: [PATCH] nbd: don't leak nbd_config

[Josef Bacik]

On Tue, May 23, 2017 at 12:38:31PM +0200, Ilya Dryomov wrote:
> nbd_config is allocated in nbd_alloc_config(), but never freed.
> 
> Fixes: 5ea8d10802ec ("nbd: separate out the config information")
> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
> ---
>  drivers/block/nbd.c | 1 +
>  1 file changed, 1 insertion(+)
> 

Oops, thanks Ilya

Reviewed-by: Josef Bacik <jbacik@fb.com>

Josef

Re: [PATCH] nbd: don't leak nbd_config

[Jens Axboe]

On 05/23/2017 08:14 AM, Josef Bacik wrote:
> On Tue, May 23, 2017 at 12:38:31PM +0200, Ilya Dryomov wrote:
>> nbd_config is allocated in nbd_alloc_config(), but never freed.
>>
>> Fixes: 5ea8d10802ec ("nbd: separate out the config information")
>> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
>> ---
>>  drivers/block/nbd.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
> 
> Oops, thanks Ilya
> 
> Reviewed-by: Josef Bacik <jbacik@fb.com>

Since config is referenced, why isn't this done in nbd_config_put()
instead?

-- 
Jens Axboe

Re: [PATCH] nbd: don't leak nbd_config

[Ilya Dryomov]

On Tue, May 23, 2017 at 4:16 PM, Jens Axboe <axboe@fb.com> wrote:
> On 05/23/2017 08:14 AM, Josef Bacik wrote:
>> On Tue, May 23, 2017 at 12:38:31PM +0200, Ilya Dryomov wrote:
>>> nbd_config is allocated in nbd_alloc_config(), but never freed.
>>>
>>> Fixes: 5ea8d10802ec ("nbd: separate out the config information")
>>> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
>>> ---
>>>  drivers/block/nbd.c | 1 +
>>>  1 file changed, 1 insertion(+)
>>>
>>
>> Oops, thanks Ilya
>>
>> Reviewed-by: Josef Bacik <jbacik@fb.com>
>
> Since config is referenced, why isn't this done in nbd_config_put()
> instead?

Josef's 5ea8d10802ec added that nbd->config = NULL to nbd_reset(), so
I followed his lead.  It could be done nbd_config_put() -- nbd_reset()
call in nbd_dev_add() looks like a no-op to me.  Josef?

Thanks,

                Ilya

Re: [PATCH] nbd: don't leak nbd_config

[Josef Bacik]

On Tue, May 23, 2017 at 04:27:56PM +0200, Ilya Dryomov wrote:
> On Tue, May 23, 2017 at 4:16 PM, Jens Axboe <axboe@fb.com> wrote:
> > On 05/23/2017 08:14 AM, Josef Bacik wrote:
> >> On Tue, May 23, 2017 at 12:38:31PM +0200, Ilya Dryomov wrote:
> >>> nbd_config is allocated in nbd_alloc_config(), but never freed.
> >>>
> >>> Fixes: 5ea8d10802ec ("nbd: separate out the config information")
> >>> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
> >>> ---
> >>>  drivers/block/nbd.c | 1 +
> >>>  1 file changed, 1 insertion(+)
> >>>
> >>
> >> Oops, thanks Ilya
> >>
> >> Reviewed-by: Josef Bacik <jbacik@fb.com>
> >
> > Since config is referenced, why isn't this done in nbd_config_put()
> > instead?
> 
> Josef's 5ea8d10802ec added that nbd->config = NULL to nbd_reset(), so
> I followed his lead.  It could be done nbd_config_put() -- nbd_reset()
> call in nbd_dev_add() looks like a no-op to me.  Josef?
> 

Yeah it used to be called more, but when I moved the config to be ref counted it
lost it's old uses and I just didn't notice enough to delete it.  Just fold that
into nbd_config_put() and call it a day.  Thanks,

Josef