Re: [PATCH] can: add protocol counter for AF_CAN sockets

[Oliver Hartkopp <socketcan@hartkopp.net>]

On 17.03.25 10:20, Marc Kleine-Budde wrote:
> On 16.03.2025 13:39:16, Oliver Hartkopp wrote:
>>
>>
>> On 14.03.25 13:31, Marc Kleine-Budde wrote:
>>> On 14.03.2025 12:39:49, Davide Caratti wrote:
>>>> The third column in the output of the following command:
>>>>
>>>>    # grep CAN /proc/net/protocols
>>>>
>>>> is systematically '0': use sock_prot_inuse_add() to account for the number
>>>> of sockets for each protocol on top of AF_CAN family.
>>>>
>>>> Signed-off-by: Davide Caratti <dcaratti@redhat.com>
>>>
>>> Applied to linux-can-next.
>>>
>>
>> Maybe too fast? E.g. J1939 is not handled.
>>
>> https://lore.kernel.org/linux-can/78951192-82b1-45bc-9903-d314c94cd182@hartkopp.net/T/#m87afc41fef8ec9099344c753e32b06f302cc0e39
> 
> Can IMHO  be added in a later patch.

Sure?

can_create() creates all CAN sockets, right?

With this patch the sock_prot_inuse_add() increases the counter by one 
for every CAN socket.

But only RAW/BCM/ISOTP are decrementing the prot-in-use counter when 
removing the socket.

IMO this patch introduces a bug.

Best regards,
Oliver