Date: Wed, 14 Jan 2004 17:45:50 +0900 (JST) From: itojun@itojun.org (Jun-ichiro itojun Hagino) To: bzeeb-lists@lists.zabbadoz.net Cc: ume@freebsd.org Subject: Re: [PATCH] IPSec fixes Message-ID: <20040114084550.8B358A0@coconut.itojun.org> In-Reply-To: Your message of "Wed, 14 Jan 2004 17:43:56 %2B0900 (JST)" <20040114084356.C894EA0@coconut.itojun.org> References: <20040114084356.C894EA0@coconut.itojun.org>
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> > > as for key_sp_unlink(), i don't think the patch is correct.
> > > even if you do not call key_sp_unlink() in key_spdflush(), spd entries
> > > will get unlink'ed in key_timehandler(). therefore the end result
> > > will be the same.
> >
> > No ! calling key_sp_unlink() from key_spdflush() will result in an
> > _extra_ call of key_freesp() and thus refcnt will be decremented
> > though it shouldn't.
> > This will result in a refcnt being 0 too early and with valid
> > pointers to that secpolicy and will further lead to "Memory accessed
> > and/or modified after free" situations somewhen after the first and
> > all successive flushes of the SPD.
> > Each part of the code checks for the state == .._DEAD when getting an
> > sp from sptree so the comment above key_spdflush() is correct. Only
> > mark the sp as dead.
> >
> > Hope this explains the problem a bit better.
>
> the refcnt decremented in key_sp_unlink() is for the link from
> sptree[]. i guess this is the proper fix. does it fix your situation?
oops.
itojun
Index: key.c
===================================================================
RCS file: /cvsroot/kame/kame/kame/sys/netkey/key.c,v
retrieving revision 1.324
diff -u -r1.324 key.c
--- key.c 14 Jan 2004 04:10:24 -0000 1.324
+++ key.c 14 Jan 2004 08:45:36 -0000
@@ -2092,9 +2092,9 @@
newsp->lifetime = lft ? lft->sadb_lifetime_addtime : 0;
newsp->validtime = lft ? lft->sadb_lifetime_usetime : 0;
- newsp->refcnt = 1; /* do not reclaim until I say I do */
newsp->state = IPSEC_SPSTATE_ALIVE;
LIST_INSERT_TAIL(&sptree[newsp->dir], newsp, secpolicy, chain);
+ newsp->refcnt++;
/* delete the entry in spacqtree */
if (mhp->msg->sadb_msg_type == SADB_X_SPDUPDATE &&
@@ -8080,9 +8080,10 @@
{
/* remove from SP index */
- if (__LIST_CHAINED(sp))
+ if (__LIST_CHAINED(sp)) {
LIST_REMOVE(sp, chain);
- key_freesp(sp);
+ key_freesp(sp);
+ }
}
/* XXX too much? */
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