Re: [PATCH 5.15 098/132] mptcp: strict local address ID selection

Mat Martineau
2022-05-24T03:56:37Z

On Mon, 23 May 2022, Greg Kroah-Hartman wrote:

> From: Paolo Abeni <pabeni@redhat.com>
>
> [ Upstream commit 4cf86ae84c718333928fd2d43168a1e359a28329 ]
>
> The address ID selection for MPJ subflows created in response
> to incoming ADD_ADDR option is currently unreliable: it happens
> at MPJ socket creation time, when the local address could be
> unknown.
>
> Additionally, if the no local endpoint is available for the local
> address, a new dummy endpoint is created, confusing the user-land.
>
> This change refactor the code to move the address ID selection inside
> the rebuild_header() helper, when the local address eventually
> selected by the route lookup is finally known. If the address used
> is not mapped by any endpoint - and thus can't be advertised/removed
> pick the id 0 instead of allocate a new endpoint.
>
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
> net/mptcp/pm_netlink.c | 13 --------
> net/mptcp/protocol.c | 3 ++
> net/mptcp/protocol.h | 3 +-
> net/mptcp/subflow.c | 67 ++++++++++++++++++++++++++++++++++++------
> 4 files changed, 63 insertions(+), 23 deletions(-)
>

Greg, Sasha -

Same issue with this patch as

[PATCH 5.17 114/158] mptcp: strict local address ID selection

so hopefully you can drop this one but keep "mptcp: Do TCP fallback on
early DSS checksum failure".

Details on the 5.17.10-rc1 thread:

https://lore.kernel.org/stable/fa953ec-288f-7715-c6fb-47a222e85270@linux.intel.com/

Thanks,

--
Mat Martineau
Intel