linux/net/tipc
Jon Paul Maloy 17b2063077 tipc: eliminate risk of premature link setup during failover
When a link goes down, and there is still a working link towards its
destination node, a failover is initiated, and the failed link is not
allowed to re-establish until that procedure is finished. To ensure
this, the concerned link endpoints are set to state LINK_FAILINGOVER,
and the node endpoints to NODE_FAILINGOVER during the failover period.

However, if the link reset is due to a disabled bearer, the corres-
ponding link endpoint is deleted, and only the node endpoint knows
about the ongoing failover. Now, if the disabled bearer is re-enabled
during the failover period, the discovery mechanism may create a new
link endpoint that is ready to be established, despite that this is not
permitted. This situation may cause both the ongoing failover and any
subsequent link synchronization to fail.

In this commit, we ensure that a newly created link goes directly to
state LINK_FAILINGOVER if the corresponding node state is
NODE_FAILINGOVER. This eliminates the problem described above.

Furthermore, we tighten the criteria for which packets are allowed
to end a failover state in the function tipc_node_check_state().
By checking that the receiving link is up and running, instead of just
checking that it is not in failover mode, we eliminate the risk that
protocol packets from the re-created link may cause the failover to
be prematurely terminated.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-23 16:14:45 -07:00
..
addr.c tipc: simplify include dependencies 2015-05-14 12:24:45 -04:00
addr.h tipc: simplify include dependencies 2015-05-14 12:24:45 -04:00
bcast.c tipc: reduce locking scope during packet reception 2015-07-20 20:41:16 -07:00
bcast.h tipc: reduce locking scope during packet reception 2015-07-20 20:41:16 -07:00
bearer.c tipc: move all link_reset() calls to link aggregation level 2015-07-30 17:25:13 -07:00
bearer.h tipc: make media xmit call outside node spinlock context 2015-07-20 20:41:15 -07:00
core.c tipc: rename functions defined in subscr.c 2015-05-04 15:04:00 -04:00
core.h tipc: clean up link creation 2015-07-30 17:25:15 -07:00
discover.c tipc: move received discovery data evaluation inside node.c 2015-07-30 17:25:14 -07:00
discover.h tipc: involve namespace infrastructure 2015-01-12 16:24:32 -05:00
eth_media.c tipc: make media address offset a common define 2015-02-27 18:18:48 -05:00
ib_media.c tipc: rename media/msg related definitions 2015-02-27 18:18:48 -05:00
Kconfig tipc: add ip/udp media type 2015-03-05 22:08:42 -05:00
link.c tipc: clean up link creation 2015-07-30 17:25:15 -07:00
link.h tipc: clean up link creation 2015-07-30 17:25:15 -07:00
Makefile tipc: add ip/udp media type 2015-03-05 22:08:42 -05:00
msg.c tipc: clean up socket layer message reception 2015-07-26 16:31:50 -07:00
msg.h tipc: remove implicit message delivery in node_unlock() 2015-07-30 17:25:14 -07:00
name_distr.c tipc: make media xmit call outside node spinlock context 2015-07-20 20:41:15 -07:00
name_distr.h tipc: resolve race problem at unicast message reception 2015-02-05 16:00:02 -08:00
name_table.c tipc: rename functions defined in subscr.c 2015-05-04 15:04:00 -04:00
name_table.h tipc: convert legacy nl name table dump to nl compat 2015-02-09 13:20:48 -08:00
net.c tipc: simplify include dependencies 2015-05-14 12:24:45 -04:00
net.h tipc: make tipc node table aware of net namespace 2015-01-12 16:24:32 -05:00
netlink_compat.c tipc: don't sanity check non-existing TLV (NL compat) 2015-08-17 10:39:54 -07:00
netlink.c tipc: move and rename the legacy nl api to "nl compat" 2015-02-09 13:20:47 -08:00
netlink.h tipc: move and rename the legacy nl api to "nl compat" 2015-02-09 13:20:47 -08:00
node.c tipc: eliminate risk of premature link setup during failover 2015-08-23 16:14:45 -07:00
node.h tipc: remove implicit message delivery in node_unlock() 2015-07-30 17:25:14 -07:00
server.c tipc: use sock_create_kern interface to create kernel socket 2015-05-14 13:39:33 -04:00
server.h tipc: make subscriber server support net namespace 2015-01-12 16:24:33 -05:00
socket.c tipc: clean up socket layer message reception 2015-07-26 16:31:50 -07:00
socket.h tipc: clean up socket layer message reception 2015-07-26 16:31:50 -07:00
subscr.c tipc: adjust locking policy of subscription 2015-05-04 15:04:01 -04:00
subscr.h tipc: rename functions defined in subscr.c 2015-05-04 15:04:00 -04:00
sysctl.c tipc: add name distributor resiliency queue 2014-09-01 17:51:48 -07:00
udp_media.c ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument 2015-07-31 15:21:30 -07:00