linux/net/x25
Martin Schiller 944e594cfa net/x25: fix call timeouts in blocking connects
When a userspace application starts a blocking connect(), a CALL REQUEST
is sent, the t21 timer is started and the connect is waiting in
x25_wait_for_connection_establishment(). If then for some reason the t21
timer expires before any reaction on the assigned logical channel (e.g.
CALL ACCEPT, CLEAR REQUEST), there is sent a CLEAR REQUEST and timer
t23 is started waiting for a CLEAR confirmation. If we now receive a
CLEAR CONFIRMATION from the peer, x25_disconnect() is called in
x25_state2_machine() with reason "0", which means "normal" call
clearing. This is ok, but the parameter "reason" is used as sk->sk_err
in x25_disconnect() and sock_error(sk) is evaluated in
x25_wait_for_connection_establishment() to check if the call is still
pending. As "0" is not rated as an error, the connect will stuck here
forever.

To fix this situation, also check if the sk->sk_state changed form
TCP_SYN_SENT to TCP_CLOSE in the meantime, which is also done by
x25_disconnect().

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Link: https://lore.kernel.org/r/20220805061810.10824-1-ms@dev.tdt.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-08 20:48:51 -07:00
..
af_x25.c net/x25: fix call timeouts in blocking connects 2022-08-08 20:48:51 -07:00
Kconfig Replace HTTP links with HTTPS ones: X.25 network layer 2020-07-07 15:44:44 -07:00
Makefile
sysctl_net_x25.c
x25_dev.c net: x25: Remove unimplemented X.25-over-LLC code stubs 2020-12-12 17:15:33 -08:00
x25_facilities.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
x25_forward.c net: x25: Use list_for_each_entry() to simplify code in x25_forward.c 2021-06-08 16:31:25 -07:00
x25_in.c net: x25: drop harmless check of !more 2021-12-09 18:35:11 -08:00
x25_link.c net: x25: Use list_for_each_entry() to simplify code in x25_link.c 2021-06-08 16:31:24 -07:00
x25_out.c
x25_proc.c x25: remove redundant pointer dev 2022-05-10 11:59:22 +02:00
x25_route.c net: x25: Use list_for_each_entry() to simplify code in x25_route.c 2021-06-10 14:08:09 -07:00
x25_subr.c net/x25: Fix null-ptr-deref in x25_disconnect 2020-04-28 14:08:59 -07:00
x25_timer.c