linux/net/l2tp
Ridge Kennedy 0d0d9a388a l2tp: Allow duplicate session creation with UDP
In the past it was possible to create multiple L2TPv3 sessions with the
same session id as long as the sessions belonged to different tunnels.
The resulting sessions had issues when used with IP encapsulated tunnels,
but worked fine with UDP encapsulated ones. Some applications began to
rely on this behaviour to avoid having to negotiate unique session ids.

Some time ago a change was made to require session ids to be unique across
all tunnels, breaking the applications making use of this "feature".

This change relaxes the duplicate session id check to allow duplicates
if both of the colliding sessions belong to UDP encapsulated tunnels.

Fixes: dbdbc73b44 ("l2tp: fix duplicate session creation")
Signed-off-by: Ridge Kennedy <ridge.kennedy@alliedtelesis.co.nz>
Acked-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-04 12:35:49 +01:00
..
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
l2tp_core.c l2tp: Allow duplicate session creation with UDP 2020-02-04 12:35:49 +01:00
l2tp_core.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
l2tp_debugfs.c l2tp: no need to check return value of debugfs_create functions 2019-06-14 08:45:05 -07:00
l2tp_eth.c net: core: add generic lockdep keys 2019-10-24 14:53:48 -07:00
l2tp_ip.c netfilter: drop bridge nf reset from nf_reset 2019-10-01 18:42:15 +02:00
l2tp_ip6.c net: ipv6: add net argument to ip6_dst_lookup_flow 2019-12-04 12:27:12 -08:00
l2tp_netlink.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
l2tp_ppp.c compat_ioctl: pppoe: fix PPPOEIOCSFWD handling 2019-07-30 14:42:13 -07:00