[linux-yocto] [PATCH] sctp: set association state to established in dupcook_a handler

[Bruce Ashfield]

On 13-06-02 10:06 PM, Xufeng Zhang wrote:
> On 06/01/2013 01:29 AM, Bruce Ashfield wrote:
>> On 13-05-31 05:11 AM, Xufeng Zhang wrote:
>>> commit 9839ff0dead906e85e4d17490aeff87a5859a157 upstream
>>>
>>
>> I assume this is for the 3.4 tree ?
> Yes.

Great.

>
>>
>> Do you know if this same commit has been submitted to the korg 3.4
>> stable tree ?
> Check the code in:
> https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/tree/net/sctp/sm_statefuns.c?id=refs/tags/v3.4.47
>
> I didn't find this commit has been submitted to 3.4 stable tree.

In that case, can you submit it there and resend the patch once it
has been sent to -stable ? If you are unsure about how to get a change
queued for stable, the kernel Documentation file stable_kernel_rules.txt,
has all the details.

Bruce

>
>
>
> Thanks,
> Xufeng
>>
>> The change looks fine, but I'd like to be sure it is also going to
>> every 3.4 kernel, and not just linux-yocto.
>>
>> Cheers,
>>
>> Bruce
>>
>>> While sctp handling a duplicate COOKIE-ECHO and the action is
>>> 'Association restart', sctp_sf_do_dupcook_a() will processing
>>> the unexpected COOKIE-ECHO for peer restart, but it does not set
>>> the association state to SCTP_STATE_ESTABLISHED, so the association
>>> could stuck in SCTP_STATE_SHUTDOWN_PENDING state forever.
>>> This violates the sctp specification:
>>>    RFC 4960 5.2.4. Handle a COOKIE ECHO when a TCB Exists
>>>    Action
>>>    A) In this case, the peer may have restarted. .....
>>>       After this, the endpoint shall enter the ESTABLISHED state.
>>>
>>> To resolve this problem, adding a SCTP_CMD_NEW_STATE cmd to the
>>> command list before SCTP_CMD_REPLY cmd, this will set the restart
>>> association to SCTP_STATE_ESTABLISHED state properly and also avoid
>>> I-bit being set in the DATA chunk header when COOKIE_ACK is bundled
>>> with DATA chunks.
>>>
>>> Signed-off-by: Xufeng Zhang <xufeng.zhang at windriver.com>
>>> Acked-by: Neil Horman <nhorman at tuxdriver.com>
>>> Acked-by: Vlad Yasevich <vyasevich at gmail.com>
>>> Signed-off-by: David S. Miller <davem at davemloft.net>
>>> ---
>>>   net/sctp/sm_statefuns.c |    4 +++-
>>>   1 files changed, 3 insertions(+), 1 deletions(-)
>>>
>>> diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
>>> index 891f5db..46ee146 100644
>>> --- a/net/sctp/sm_statefuns.c
>>> +++ b/net/sctp/sm_statefuns.c
>>> @@ -1747,8 +1747,10 @@ static sctp_disposition_t
>>> sctp_sf_do_dupcook_a(const struct sctp_endpoint *ep,
>>>
>>>       /* Update the content of current association. */
>>>       sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC,
>>> SCTP_ASOC(new_asoc));
>>> -    sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
>>>       sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
>>> +    sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
>>> +            SCTP_STATE(SCTP_STATE_ESTABLISHED));
>>> +    sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
>>>       return SCTP_DISPOSITION_CONSUME;
>>>
>>>   nomem_ev:
>>>
>>
>>
>