| Message ID | 20230815231555.6465-1-a@unstable.cc |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [Openvpn-devel] dco: fix crash when --multihome is used with --proto tcp | expand |
Acked-by: Gert Doering <gert@greenie.muc.de> Code looks good. Done a quick test on a Linux/DCO server, with TCP and --multihome. Without the patch: 2023-09-10 17:15:20 us=552871 freebsd-14-amd64/194.97.140.5:33293 MULTI: primary virtual IPv6 for freebsd-14-amd64/194.97.140.5:33293: fd00:abcd:220:1::1002 Segmentation fault (core dumped) with the patch: 2023-09-10 17:16:57 us=590075 freebsd-14-amd64/194.97.140.5:41489 MULTI: primary virtual IPv6 for freebsd-14-amd64/194.97.140.5:41489: fd00:abcd:220:1::1002 2023-09-10 17:16:57 us=590252 freebsd-14-amd64/194.97.140.5:41489 Data Channel MTU parms [ mss_fix:1366 max_frag:0 tun_mtu:1500 tun_max_mtu:1600 headroom:136 payload:1768 tailroom:562 ET:0 ] 2023-09-10 17:16:57 us=590348 freebsd-14-amd64/194.97.140.5:41489 Outgoing dynamic tls-crypt: Cipher 'AES-256-CTR' initialized with 256 bit key .. "and it just works". Since the logic for "what do we need to do differently?" is the same as for the non-DCO case now, I have not done more in-depth tests (though I maybe *should* set up a server with multiple v4+v6 addresses and run client tests against either one). I have adjusted the github tag - our established format is Github: fixes OpenVPN/openvpn#390 not anything else. Your patch has been applied to the master and release/2.6 branch (bugfix). commit 0793eb105c5720c4eb31af71c9db81459439e510 (master) commit 70ef43f2b9b938256e0f689f4ddba0d6fbb3a371 (release/2.6) Author: Antonio Quartulli Date: Wed Aug 16 01:15:55 2023 +0200 dco: fix crash when --multihome is used with --proto tcp Signed-off-by: Antonio Quartulli <a@unstable.cc> Acked-by: Gert Doering <gert@greenie.muc.de> Message-Id: <20230815231555.6465-1-a@unstable.cc> URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg26953.html Signed-off-by: Gert Doering <gert@greenie.muc.de> -- kind regards, Gert Doering
diff --git a/src/openvpn/dco.c b/src/openvpn/dco.c index 7c7eaac4..cd3e0ad3 100644 --- a/src/openvpn/dco.c +++ b/src/openvpn/dco.c @@ -509,7 +509,7 @@ dco_multi_get_localaddr(struct multi_context *m, struct multi_instance *mi, #if ENABLE_IP_PKTINFO struct context *c = &mi->context; - if (!(c->options.sockflags & SF_USE_IP_PKTINFO)) + if (!proto_is_udp(c->c2.link_socket->info.proto) || !(c->options.sockflags & SF_USE_IP_PKTINFO)) { return false; }
Although it's a combination of options that is not really useful, when specifying --multihome along with --proto tcp and DCO is enabled, OpenVPN will crash while attempting to access c2.link_socket_actual (NULL for the TCP case) in order to retrieve the local address (in function dco_multi_get_localaddr()) Prevent crash by running this code only if proto is UDP. The same check is already performed in socket.c/h for the non-DCO case. Fixes: https://github.com/OpenVPN/openvpn/issues/390 Change-Id: I61adc26ce2ff737e020c3d980902a46758cb23e5 Signed-off-by: Antonio Quartulli <a@unstable.cc> --- src/openvpn/dco.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)