From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 29 Jan 2008 10:07:37 -0600 From: Robin Holt Subject: Re: [patch 1/6] mmu_notifier: Core code Message-ID: <20080129160737.GV3058@sgi.com> References: <20080128202840.974253868@sgi.com> <20080128202923.609249585@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080128202923.609249585@sgi.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: Andrea Arcangeli , Robin Holt , Avi Kivity , Izik Eidus , Nick Piggin , kvm-devel@lists.sourceforge.net, Benjamin Herrenschmidt , Peter Zijlstra , steiner@sgi.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, daniel.blueman@quadrics.com, Hugh Dickins List-ID: I am going to seperate my comments into individual replies to help reduce the chance they are lost. > +void mmu_notifier_release(struct mm_struct *mm) ... > + hlist_for_each_entry_safe_rcu(mn, n, t, > + &mm->mmu_notifier.head, hlist) { > + if (mn->ops->release) > + mn->ops->release(mn, mm); > + hlist_del(&mn->hlist); This is a use-after-free issue. The hlist_del_rcu needs to be done before the callout as the structure containing the mmu_notifier structure will need to be freed from within the ->release callout. Thanks, Robin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org