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Date: Tue, 9 Jul 2024 07:12:45 +0200
From: Christian Brauner <brauner@kernel.org>
To: =?utf-8?Q?Micka=C3=ABl_Sala=C3=BCn?= <mic@digikod.net>
Cc: Kees Cook <kees@kernel.org>, Steven Rostedt <rostedt@goodmis.org>, 
	Paul Moore <paul@paul-moore.com>, Jann Horn <jannh@google.com>, 
	"Paul E. McKenney" <paulmck@kernel.org>, Casey Schaufler <casey@schaufler-ca.com>, 
	syzbot <syzbot+5446fbf332b0602ede0b@syzkaller.appspotmail.com>, jmorris@namei.org, linux-kernel@vger.kernel.org, 
	linux-security-module@vger.kernel.org, serge@hallyn.com, syzkaller-bugs@googlegroups.com, 
	linux-fsdevel@vger.kernel.org
Subject: Re: [syzbot] [lsm?] general protection fault in
 hook_inode_free_security
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In-Reply-To: <20240708.hohNgieja0av@digikod.net>

> bypass?  Shouldn't we call all the inode_free_security() hooks in
> inode_free_by_rcu()?  That would mean to reserve an rcu_head and then
> probably use inode->i_rcu instead.

Note that you can't block in call_rcu(). From a cursory look at the
implementers of the hook it should be fine though.