Hi Greg,
On 30/08/2024 12:26, gregkh@linuxfoundation.org wrote:
The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
Thank you for the notification!
(...)
------------------ original commit in Linus's tree ------------------
From 57f86203b41c98b322119dfdbb1ec54ce5e3369b Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" matttbe@kernel.org Date: Wed, 28 Aug 2024 08:14:37 +0200 Subject: [PATCH] mptcp: pm: ADD_ADDR 0 is not a new address
The ADD_ADDR 0 with the address from the initial subflow should not be considered as a new address: this is not something new. If the host receives it, it simply means that the address is available again.
When receiving an ADD_ADDR for the ID 0, the PM already doesn't consider it as new by not incrementing the 'add_addr_accepted' counter. But the 'accept_addr' might not be set if the limit has already been reached: this can be bypassed in this case. But before, it is important to check that this ADD_ADDR for the ID 0 is for the same address as the initial subflow. If not, it is not something that should happen, and the ADD_ADDR can be ignored.
Note that if an ADD_ADDR is received while there is already a subflow opened using the same address, this ADD_ADDR is ignored as well. It means that if multiple ADD_ADDR for ID 0 are received, there will not be any duplicated subflows created by the client.
Fixes: d0876b2284cf ("mptcp: add the incoming RM_ADDR support")
The code is too different in v5.10, and I don't think it is worth it to have this small fix in v5.10.
Cheers, Matt