CVE-2026-63971

In the Linux kernel, the following vulnerability has been resolved:

sctp: fix race between sctp_wait_for_connect and peeloff

sctp_wait_for_connect() drops and re-acquires the socket lock while

waiting for the association to reach ESTABLISHED state. During this

window, another thread can peeloff the association to a new socket via

getsockopt(SCTP_SOCKOPT_PEELOFF), changing asoc->base.sk. After

re-acquiring the old socket lock, sctp_wait_for_connect() returns

success without noticing the migration — the caller then accesses

the association under the wrong lock in sctp_datamsg_from_user().

Add the same sk != asoc->base.sk check that sctp_wait_for_sndbuf()

already has, returning an error if the association was migrated while

we slept.