linux/net/xfrm
Jonathan Basseri 2b06cdf3e6 xfrm: Clear sk_dst_cache when applying per-socket policy.
If a socket has a valid dst cache, then xfrm_lookup_route will get
skipped. However, the cache is not invalidated when applying policy to a
socket (i.e. IPV6_XFRM_POLICY). The result is that new policies are
sometimes ignored on those sockets. (Note: This was broken for IPv4 and
IPv6 at different times.)

This can be demonstrated like so,
1. Create UDP socket.
2. connect() the socket.
3. Apply an outbound XFRM policy to the socket. (setsockopt)
4. send() data on the socket.

Packets will continue to be sent in the clear instead of matching an
xfrm or returning a no-match error (EAGAIN). This affects calls to
send() and not sendto().

Invalidating the sk_dst_cache is necessary to correctly apply xfrm
policies. Since we do this in xfrm_user_policy(), the sk_lock was
already acquired in either do_ip_setsockopt() or do_ipv6_setsockopt(),
and we may call __sk_dst_reset().

Performance impact should be negligible, since this code is only called
when changing xfrm policy, and only affects the socket in question.

Fixes: 00bc0ef588 ("ipv6: Skip XFRM lookup if dst_entry in socket cache is valid")
Tested: https://android-review.googlesource.com/517555
Tested: https://android-review.googlesource.com/418659
Signed-off-by: Jonathan Basseri <misterikkit@google.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2017-10-26 08:19:03 +02:00
..
Kconfig Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2017-02-16 21:25:49 -05:00
Makefile xfrm: fix xfrm_dev_event() missing when compile without CONFIG_XFRM_OFFLOAD 2017-06-07 08:16:27 +02:00
xfrm_algo.c xfrm: use IS_ENABLED() instead of checking for built-in or module 2016-09-10 21:19:11 -07:00
xfrm_device.c xfrm: Fix negative device refcount on offload failure. 2017-09-11 10:36:51 +02:00
xfrm_hash.c
xfrm_hash.h xfrm: use "unsigned int" in __xfrm6_pref_hash() 2017-03-24 07:03:12 +01:00
xfrm_input.c vti: fix NULL dereference in xfrm_input() 2017-09-13 10:15:24 +02:00
xfrm_ipcomp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-11-04 13:48:30 -05:00
xfrm_output.c net: xfrm: support setting an output mark. 2017-08-11 07:03:00 +02:00
xfrm_policy.c xfrm: Fix xfrm_dst_cache memleak 2017-10-24 13:40:36 +02:00
xfrm_proc.c proc: Reduce cache miss in xfrm_statistics_seq_show 2016-09-30 01:50:45 -04:00
xfrm_replay.c xfrm: Add xfrm_replay_overflow functions for offloading 2017-04-14 10:07:01 +02:00
xfrm_state.c xfrm: Clear sk_dst_cache when applying per-socket policy. 2017-10-26 08:19:03 +02:00
xfrm_sysctl.c net: xfrm: Change u32 sysctl entries to use proc_douintvec 2016-09-07 23:17:53 -07:00
xfrm_user.c ipsec: Fix aborted xfrm policy dump crash 2017-10-23 09:35:48 +02:00