From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751424AbeBIPjN (ORCPT ); Fri, 9 Feb 2018 10:39:13 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:56128 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751038AbeBIPjL (ORCPT ); Fri, 9 Feb 2018 10:39:11 -0500 Date: Fri, 9 Feb 2018 17:39:10 +0200 From: "Michael S. Tsirkin" To: Jason Wang Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH V4 1/2] ptr_ring: fail early if queue occupies more than KMALLOC_MAX_SIZE Message-ID: <20180209173856-mutt-send-email-mst@kernel.org> References: <1518169550-5987-1-git-send-email-jasowang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1518169550-5987-1-git-send-email-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 09, 2018 at 05:45:49PM +0800, Jason Wang wrote: > To avoid slab to warn about exceeded size, fail early if queue > occupies more than KMALLOC_MAX_SIZE. > > Reported-by: syzbot+e4d4f9ddd4295539735d@syzkaller.appspotmail.com > Fixes: 2e0ab8ca83c12 ("ptr_ring: array based FIFO for pointers") > Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin > --- > include/linux/ptr_ring.h | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/include/linux/ptr_ring.h b/include/linux/ptr_ring.h > index 1883d61..6051a5f 100644 > --- a/include/linux/ptr_ring.h > +++ b/include/linux/ptr_ring.h > @@ -466,6 +466,8 @@ static inline int ptr_ring_consume_batched_bh(struct ptr_ring *r, > > static inline void **__ptr_ring_init_queue_alloc(unsigned int size, gfp_t gfp) > { > + if (size * sizeof(void *) > KMALLOC_MAX_SIZE) > + return NULL; > return kcalloc(size, sizeof(void *), gfp); > } > > -- > 2.7.4