• Daniel Borkmann's avatar
    tcp, ulp: remove socket lock assertion on ULP cleanup · aadd4355
    Daniel Borkmann authored
    Eric reported that syzkaller triggered a splat in tcp_cleanup_ulp()
    where assertion sock_owned_by_me() failed. This happened through
    inet_csk_prepare_forced_close() first releasing the socket lock,
    then calling into tcp_done(newsk) which is called after the
    inet_csk_prepare_forced_close() and therefore without the socket
    lock held. The sock_owned_by_me() assertion can generally be
    removed as the only place where tcp_cleanup_ulp() is called from
    now is out of inet_csk_destroy_sock() -> sk->sk_prot->destroy()
    where socket is in dead state and unreachable. Therefore, add a
    comment why the check is not needed instead.
    Fixes: 8b9088f8 ("tcp, ulp: enforce sock_owned_by_me upon ulp init and cleanup")
    Reported-by: default avatarEric Dumazet <edumazet@google.com>
    Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
tcp_ulp.c 3 KB