CVE-2024-45010 Information

Description

In the Linux kernel the following vulnerability has been resolved:

mptcp: pm: only mark ‘subflow’ endp as available

Adding the following warning …

WARN_ON_ONCE(msk->pm.local_addr_used == 0)

… before decrementing the local_addr_used counter helped to find a bug when running the emove single address\ subtest from the mptcp_join.sh selftests.

Removing a ‘signal’ endpoint will trigger the removal of all subflows linked to this endpoint via mptcp_pm_nl_rm_addr_or_subflow() with rm_type == MPTCP_MIB_RMSUBFLOW. This will decrement the local_addr_used counter which is wrong in this case because this counter is linked to ‘subflow’ endpoints and here it is a ‘signal’ endpoint that is being removed.

Now the counter is decremented only if the ID is being used outside of mptcp_pm_nl_rm_addr_or_subflow() only for ‘subflow’ endpoints and if the ID is not 0 – local_addr_used is not taking into account these ones. This marking of the ID as being available and the decrement is done no matter if a subflow using this ID is currently available because the subflow could have been closed before.

Reference

https://git.kernel.org/stable/c/7fdc870d08960961408a44c569f20f50940e7d4f https://git.kernel.org/stable/c/43cf912b0b0fc7b4fd12cbc735d1f5afb8e1322d https://git.kernel.org/stable/c/9849cfc67383ceb167155186f8f8fe8a896b60b3 https://git.kernel.org/stable/c/322ea3778965da72862cca2a0c50253aacf65fe6