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Tue, 20 Oct 2026 00:27:31 -0700 (PDT) Date: Tue, 20 Oct 2026 03:27:28 -0400 From: "Michael S. Tsirkin" To: Linus Torvalds Cc: Wang Haoran , jasowangio@gmail.com, kvm@vger.kernel.org, virtualization@lists.linux.dev, netdev@vger.kernel.org, eperezma@redhat.com Subject: Re: [BUG] vhost/vringh: __get_user without access_ok leaks kernel memory via vDPA passthrough Message-ID: <20261020032524-mutt-send-email-mst@kernel.org> References: <6ad07f8a.a0c71a5e.2d2efd.977a@mx.google.com> <20261018152358-mutt-send-email-mst@kernel.org> <20261018174250-mutt-send-email-mst@kernel.org> <376ef9d0-b03f-4f85-aee5-46cf20eb00ae@gmail.com> <20261020021924-mutt-send-email-mst@kernel.org> X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 9NxQIDJ8_dHyN7zy_r4B8AxsgeE-eQ5HDeB28VAsBaw_1792481253 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Oct 19, 2026 at 08:51:43PM -1000, Linus Torvalds wrote: > On Mon, 19 Oct 2026 at 20:31, Michael S. Tsirkin wrote: > > > > The following seems to work for me. Testing would be appreciated. > > I have a whole branch that removes __get_user() and __put_user() entirely. > > Somebody should check that I did it right. But I didn't want to do the > pagefault_disable() around the vringh_notify() part, so it's not quite > the same as yours. > > Let me just push it out. I was going to let it simmer, but your email > made me go "I should just let more people look at it". > > Mind taking a look at the 'uaccess-cleanups' branch? At the virtio things there? Sure, 'bit later. > It builds for me. That's all the testing it has gotten so far. Blush. > > Linus I can help with that.