linux-stable/include/net/sctp
Xin Long 6b84202c94 sctp: fix the check for _sctp_walk_params and _sctp_walk_errors
Commit b1f5bfc27a ("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: b1f5bfc27a ("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
..
auth.h net, sctp: convert sctp_auth_bytes.refcnt from atomic_t to refcount_t 2017-07-04 22:35:18 +01:00
checksum.h include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
command.h sctp: remove the typedef sctp_init_chunk_t 2017-07-01 09:08:42 -07:00
constants.h sctp: remove the typedef sctp_data_chunk_t 2017-07-01 09:08:42 -07:00
sctp.h sctp: fix the check for _sctp_walk_params and _sctp_walk_errors 2017-07-27 00:03:12 -07:00
sm.h sctp: remove the typedef sctp_data_chunk_t 2017-07-01 09:08:42 -07:00
structs.h net, sctp: convert sctp_ep_common.refcnt from atomic_t to refcount_t 2017-07-04 22:35:19 +01:00
tsnmap.h sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
ulpevent.h sctp: add support for generating add stream change event notification 2017-03-12 23:22:23 -07:00
ulpqueue.h sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00