Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753352AbbFKCQb (ORCPT ); Wed, 10 Jun 2015 22:16:31 -0400 Received: from us01smtprelay-2.synopsys.com ([198.182.60.111]:40968 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751555AbbFKCQV convert rfc822-to-8bit (ORCPT ); Wed, 10 Jun 2015 22:16:21 -0400 From: John Youn To: Yunzhi Li , "John.Youn@synopsys.com" CC: "heiko@sntech.de" , "cf@rock-chips.com" , "hl@rock-chips.com" , "yk@rock-chips.com" , "gauravsh@google.com" , "alberto@google.com" , "wulf@rock-chips.com" , "jwerner@chromium.org" , "jeffy.chen@rock-chips.com" , "gregory.herrero@intel.com" , "yousaf.kaukab@intel.com" , "huangtao@rock-chips.com" , "rockchip-discuss@chromium.org" , Greg Kroah-Hartman , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v1] usb: dwc2: gadget: fix a memory use-after-free bug Thread-Topic: [PATCH v1] usb: dwc2: gadget: fix a memory use-after-free bug Thread-Index: AQHQmc+GFAYX4n+uRk6+BwW7GkNODA== Date: Thu, 11 Jun 2015 02:16:19 +0000 Message-ID: <2B3535C5ECE8B5419E3ECBE3007729090175248590@US01WEMBX2.internal.synopsys.com> References: <1432876946-4975-1-git-send-email-lyz@rock-chips.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.10.161.119] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4314 Lines: 85 On 5/28/2015 10:22 PM, Yunzhi Li wrote: > When s3c_hsotg_handle_unaligned_buf_complete() hs_req->req.buf > already destroyed, in s3c_hsotg_unmap_dma(), it touches > hs_req->req.dma again, so s3c_hsotg_unmap_dma() should be called > before s3c_hsotg_handle_unaligned_buf_complete(). Otherwise, it > will cause a bad_page BUG, when allocate this memory page next > time. > > This bug led to the following crash: > > BUG: Bad page state in process swapper/0 pfn:2bdbc > [ 26.820440] page:eed76780 count:0 mapcount:0 mapping: (null) index:0x0 > [ 26.854710] page flags: 0x200(arch_1) > [ 26.885836] page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set > [ 26.919179] bad because of flags: > [ 26.948917] page flags: 0x200(arch_1) > [ 26.979100] Modules linked in: > [ 27.008401] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W3.14.0 #17 > [ 27.041816] [] (unwind_backtrace) from [] (show_stack+0x20/0x24) > [ 27.076108] [] (show_stack) from [] (dump_stack+0x70/0x8c) > [ 27.110246] [] (dump_stack) from [] (bad_page+0xfc/0x12c) > [ 27.143958] [] (bad_page) from [] (get_page_from_freelist+0x3e4/0x50c) > [ 27.179298] [] (get_page_from_freelist) from [] (__alloc_pages_nodemask) > [ 27.216296] [] (__alloc_pages_nodemask) from [] (__get_free_pages+0x20/) > [ 27.252326] [] (__get_free_pages) from [] (kmalloc_order_trace+0x34/0xa) > [ 27.288295] [] (kmalloc_order_trace) from [] (__kmalloc+0x40/0x1ac) > [ 27.323751] [] (__kmalloc) from [] (s3c_hsotg_ep_queue.isra.12+0x7c/0x1) > [ 27.359937] [] (s3c_hsotg_ep_queue.isra.12) from [] (s3c_hsotg_ep_queue) > [ 27.397478] [] (s3c_hsotg_ep_queue_lock) from [] (rx_submit+0xfc/0x164) > [ 27.433619] [] (rx_submit) from [] (rx_complete+0x22c/0x230) > [ 27.468872] [] (rx_complete) from [] (s3c_hsotg_complete_request+0xfc/0) > [ 27.506240] [] (s3c_hsotg_complete_request) from [] (s3c_hsotg_handle_o) > [ 27.545401] [] (s3c_hsotg_handle_outdone) from [] (s3c_hsotg_epint+0x2c) > [ 27.583689] [] (s3c_hsotg_epint) from [] (s3c_hsotg_irq+0x1dc/0x4ac) > [ 27.621041] [] (s3c_hsotg_irq) from [] (handle_irq_event_percpu+0x70/0x) > [ 27.659066] [] (handle_irq_event_percpu) from [] (handle_irq_event+0x4c) > [ 27.697322] [] (handle_irq_event) from [] (handle_fasteoi_irq+0xc8/0x11) > [ 27.735451] [] (handle_fasteoi_irq) from [] (generic_handle_irq+0x30/0x) > [ 27.773918] [] (generic_handle_irq) from [] (__handle_domain_irq+0x84/0) > [ 27.812018] [] (__handle_domain_irq) from [] (gic_handle_irq+0x48/0x6c) > [ 27.849695] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x50) > [ 27.886907] Exception stack(0xc0d01ee0 to 0xc0d01f28) > > Signed-off-by: Yunzhi Li > > --- > > drivers/usb/dwc2/gadget.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c > index 6a30887..8070602 100644 > --- a/drivers/usb/dwc2/gadget.c > +++ b/drivers/usb/dwc2/gadget.c > @@ -1389,14 +1389,14 @@ static void s3c_hsotg_complete_request(struct dwc2_hsotg *hsotg, > if (hs_req->req.status == -EINPROGRESS) > hs_req->req.status = result; > > + if (using_dma(hsotg)) > + s3c_hsotg_unmap_dma(hsotg, hs_ep, hs_req); > + > s3c_hsotg_handle_unaligned_buf_complete(hsotg, hs_ep, hs_req); > > hs_ep->req = NULL; > list_del_init(&hs_req->queue); > > - if (using_dma(hsotg)) > - s3c_hsotg_unmap_dma(hsotg, hs_ep, hs_req); > - > /* > * call the complete request with the locks off, just in case the > * request tries to queue more work for this endpoint. > Acked-by: John Youn John -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/