tcp: fix various issues for sockets morphing to listen state
[ Upstream commit 02b2faaf0af1d85585f6d6980e286d53612acfc2 ]
Dmitry Vyukov reported a divide by 0 triggered by syzkaller, exploiting
tcp_disconnect() path that was never really considered and/or used
before syzkaller ;)
I was not able to reproduce the bug, but it seems issues here are the
three possible actions that assumed they would never trigger on a
listener.
1) tcp_write_timer_handler
2) tcp_delack_timer_handler
3) MTU reduction
Only IPv6 MTU reduction was properly testing TCP_CLOSE and TCP_LISTEN
states from tcp_v6_mtu_reduced()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2 files changed