Xin Long 6b84202c94 sctp: fix the check for _sctp_walk_params and _sctp_walk_errors
Commit b1f5bfc27a19 ("sctp: don't dereference ptr before leaving
_sctp_walk_{params, errors}()") tried to fix the issue that it
may overstep the chunk end for _sctp_walk_{params, errors} with
'chunk_end > offset(length) + sizeof(length)'.

But it introduced a side effect: When processing INIT, it verifies
the chunks with 'param.v == chunk_end' after iterating all params
by sctp_walk_params(). With the check 'chunk_end > offset(length)
+ sizeof(length)', it would return when the last param is not yet
accessed. Because the last param usually is fwdtsn supported param
whose size is 4 and 'chunk_end == offset(length) + sizeof(length)'

This is a badly issue even causing sctp couldn't process 4-shakes.
Client would always get abort when connecting to server, due to
the failure of INIT chunk verification on server.

The patch is to use 'chunk_end <= offset(length) + sizeof(length)'
instead of 'chunk_end < offset(length) + sizeof(length)' for both
_sctp_walk_params and _sctp_walk_errors.

Fixes: b1f5bfc27a19 ("sctp: don't dereference ptr before leaving _sctp_walk_{params, errors}()")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-27 00:03:12 -07:00
..
2017-07-11 06:08:58 -04:00
2017-04-05 10:15:20 +02:00
2017-04-24 12:35:56 -04:00
2016-07-08 12:20:57 +02:00
2016-04-25 16:44:27 -04:00
2016-04-25 16:44:27 -04:00
2016-06-09 23:41:03 -07:00
2015-03-06 21:50:02 -05:00
2015-09-17 17:18:37 -07:00
2016-02-16 20:21:48 -05:00
2017-04-14 10:06:42 +02:00
2017-04-03 19:04:48 -07:00
2016-05-20 18:03:16 -04:00
2016-04-27 22:48:25 -04:00
2017-02-03 15:16:45 -05:00
2017-06-15 12:12:40 -04:00
2017-06-17 22:54:01 -04:00
2017-04-13 13:19:48 -04:00
2016-08-17 19:36:23 -04:00
2016-10-03 02:00:22 -04:00
2016-10-04 02:11:51 -04:00
2016-07-08 12:20:57 +02:00
2016-03-23 22:09:58 -04:00
2016-12-25 17:21:22 +01:00
2017-06-17 22:54:00 -04:00
2017-01-09 16:07:41 -05:00
2015-03-12 22:58:12 -04:00
2017-06-15 12:12:40 -04:00
2016-05-03 16:08:14 -04:00
2015-10-26 22:24:22 -07:00