CVS commit: src/sys/netipsec

["Ryota Ozaki" <ozaki-r%netbsd.org@localhost>]

Module Name:    src
Committed By:   ozaki-r
Date:           Wed Aug  9 04:29:36 UTC 2017

Modified Files:
        src/sys/netipsec: key.c

Log Message:
Fix deadlock between key_sendup_mbuf called from key_acquire and localcount_drain

If we call key_sendup_mbuf from key_acquire that is called on packet
processing, a deadlock can happen like this:
- At key_acquire, a reference to an SP (and an SA) is held
- key_sendup_mbuf will try to take key_so_mtx
- Some other thread may try to localcount_drain to the SP with
  holding key_so_mtx in say key_api_spdflush
- In this case localcount_drain never return because key_sendup_mbuf
  that has stuck on key_so_mtx never release a reference to the SP

Fix the deadlock by deferring key_sendup_mbuf to the timer
(key_timehandler).


To generate a diff of this commit:
cvs rdiff -u -r1.219 -r1.220 src/sys/netipsec/key.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.