From: Al Viro <viro@ZenIV.linux.org.uk>
To: Eric Paris <eparis@parisplace.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
LKML <linux-kernel@vger.kernel.org>,
Stephen Smalley <sds@tycho.nsa.gov>,
James Morris <james.l.morris@oracle.com>,
Paul Moore <paul@paul-moore.com>,
Andrew Morton <akpm@linux-foundation.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
stable <stable@vger.kernel.org>
Subject: Re: [PATCH] SELinux: Fix possible NULL pointer dereference in selinux_inode_permission()
Date: Thu, 9 Jan 2014 22:13:03 +0000 [thread overview]
Message-ID: <20140109221303.GI10323@ZenIV.linux.org.uk> (raw)
In-Reply-To: <CACLa4pv+EUGHO+MKj8ckhmi8YKiTNVL9pSM+DDsjg+0jbjOCcA@mail.gmail.com>
On Thu, Jan 09, 2014 at 10:31:55AM -0500, Eric Paris wrote:
> Didn't Al find this/something very similar. I really hate this
> solution. Why should every LSM try to understand the intimate
> lifetime rules of the parent subsystems? The real problem is that
> inode_free_security() is being called while the inode is still in use.
> While I agree with the assessment, I disagree with the solution. Let
> me try to find where Al and Christoph talked about this....
Because LSM has stuck its fingers into the guts of those filesystems,
obviously.
Just RCU-delay freeing the damn thing and treat NULL ->i_security in
->permission() (which can happen only with MAY_NOT_BLOCK in mask) as
"return -ECHILD and let the caller deal with that".
Modifying every ->destroy_inode() is obviously wrong - there's a lot more
filesystems than LSM buggers in the tree.
next prev parent reply other threads:[~2014-01-09 22:13 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-09 15:19 [PATCH] SELinux: Fix possible NULL pointer dereference in selinux_inode_permission() Steven Rostedt
2014-01-09 15:31 ` Eric Paris
2014-01-09 15:51 ` Steven Rostedt
2014-01-09 15:57 ` Eric Paris
2014-01-09 16:05 ` Eric Paris
2014-01-09 16:10 ` Stephen Smalley
2014-01-09 16:22 ` Steven Rostedt
2014-01-09 16:25 ` Eric Paris
2014-01-09 20:20 ` Mimi Zohar
2014-01-09 20:24 ` Eric Paris
2014-01-09 22:28 ` Al Viro
2014-01-09 22:17 ` Al Viro
2014-01-09 22:13 ` Al Viro [this message]
2014-01-09 22:18 ` Eric Paris
2014-01-09 22:25 ` Al Viro
2014-01-09 22:45 ` Eric Paris
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