linux/net/sctp
Tommi Rantala 4a31a6b19f sctp: fix dst refcnt leak in sctp_v4_get_dst
Fix dst reference count leak in sctp_v4_get_dst() introduced in commit
410f03831 ("sctp: add routing output fallback"):

When walking the address_list, successive ip_route_output_key() calls
may return the same rt->dst with the reference incremented on each call.

The code would not decrement the dst refcount when the dst pointer was
identical from the previous iteration, causing the dst refcnt leak.

Testcase:
  ip netns add TEST
  ip netns exec TEST ip link set lo up
  ip link add dummy0 type dummy
  ip link add dummy1 type dummy
  ip link add dummy2 type dummy
  ip link set dev dummy0 netns TEST
  ip link set dev dummy1 netns TEST
  ip link set dev dummy2 netns TEST
  ip netns exec TEST ip addr add 192.168.1.1/24 dev dummy0
  ip netns exec TEST ip link set dummy0 up
  ip netns exec TEST ip addr add 192.168.1.2/24 dev dummy1
  ip netns exec TEST ip link set dummy1 up
  ip netns exec TEST ip addr add 192.168.1.3/24 dev dummy2
  ip netns exec TEST ip link set dummy2 up
  ip netns exec TEST sctp_test -H 192.168.1.2 -P 20002 -h 192.168.1.1 -p 20000 -s -B 192.168.1.3
  ip netns del TEST

In 4.4 and 4.9 kernels this results to:
  [  354.179591] unregister_netdevice: waiting for lo to become free. Usage count = 1
  [  364.419674] unregister_netdevice: waiting for lo to become free. Usage count = 1
  [  374.663664] unregister_netdevice: waiting for lo to become free. Usage count = 1
  [  384.903717] unregister_netdevice: waiting for lo to become free. Usage count = 1
  [  395.143724] unregister_netdevice: waiting for lo to become free. Usage count = 1
  [  405.383645] unregister_netdevice: waiting for lo to become free. Usage count = 1
  ...

Fixes: 410f03831 ("sctp: add routing output fallback")
Fixes: 0ca50d12f ("sctp: fix src address selection if using secondary addresses")
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-05 21:21:51 -05:00
..
associola.c sctp: implement enqueue_event for sctp_stream_interleave 2017-12-11 11:23:05 -05:00
auth.c sctp: remove the typedef sctp_hmac_algo_param_t 2017-07-16 20:52:14 -07:00
bind_addr.c sctp: remove the typedef sctp_scope_t 2017-08-06 21:33:41 -07:00
chunk.c sctp: implement enqueue_event for sctp_stream_interleave 2017-12-11 11:23:05 -05:00
debug.c sctp: add SCTP_CID_RECONF conversion in sctp_cname 2017-12-18 13:21:46 -05:00
endpointola.c net: tracepoint: using sock_set_state tracepoint to trace SCTP state transition 2017-12-20 14:00:25 -05:00
input.c sctp: fix the handling of ICMP Frag Needed for too small MTUs 2018-01-08 14:19:13 -05:00
inqueue.c sctp: remove the typedef sctp_chunkhdr_t 2017-07-01 09:08:41 -07:00
ipv6.c sctp: fix dst refcnt leak in sctp_v6_get_dst() 2018-02-05 21:21:13 -05:00
Kconfig net: sctp: Remove debug SCTP probe module 2018-01-02 14:27:29 -05:00
Makefile net: sctp: Remove debug SCTP probe module 2018-01-02 14:27:29 -05:00
objcnt.c sctp: remove the typedef sctp_dbg_objcnt_entry_t 2017-08-11 10:02:43 -07:00
offload.c gso: validate gso_type in GSO handlers 2018-01-22 16:01:30 -05:00
output.c sctp: implement assign_number for sctp_stream_interleave 2017-12-11 11:23:04 -05:00
outqueue.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-01-17 00:10:42 -05:00
primitive.c sctp: remove the typedef sctp_subtype_t 2017-08-06 21:33:42 -07:00
proc.c net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
protocol.c sctp: fix dst refcnt leak in sctp_v4_get_dst 2018-02-05 21:21:51 -05:00
sctp_diag.c sctp: Fix a big endian bug in sctp_diag_dump() 2017-09-26 21:16:29 -07:00
sm_make_chunk.c sctp: removed unused var from sctp_make_auth 2018-01-15 13:59:42 -05:00
sm_sideeffect.c net: tracepoint: using sock_set_state tracepoint to trace SCTP state transition 2017-12-20 14:00:25 -05:00
sm_statefuns.c net: sctp: Add SCTP ACK tracking trace event 2018-01-02 14:27:29 -05:00
sm_statetable.c sctp: implement validate_ftsn for sctp_stream_interleave 2017-12-15 13:52:22 -05:00
socket.c Currently, hardened usercopy performs dynamic bounds checking on slab 2018-02-03 16:25:42 -08:00
stream_interleave.c sctp: implement handle_ftsn for sctp_stream_interleave 2017-12-15 13:52:22 -05:00
stream_sched_prio.c sctp: remove extern from stream sched 2017-11-28 11:00:13 -05:00
stream_sched_rr.c sctp: remove extern from stream sched 2017-11-28 11:00:13 -05:00
stream_sched.c sctp: add stream interleave support in stream scheduler 2017-12-15 13:52:22 -05:00
stream.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-01-09 10:37:00 -05:00
sysctl.c sctp: support sysctl to allow users to use stream interleave 2017-12-15 13:52:22 -05:00
transport.c sctp: fix the handling of ICMP Frag Needed for too small MTUs 2018-01-08 14:19:13 -05:00
tsnmap.c
ulpevent.c sctp: implement abort_pd for sctp_stream_interleave 2017-12-11 11:23:05 -05:00
ulpqueue.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-12-22 11:16:31 -05:00