From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83337C10F00 for ; Sat, 7 Mar 2020 13:15:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 48F7E2075A for ; Sat, 7 Mar 2020 13:15:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726154AbgCGNPe (ORCPT ); Sat, 7 Mar 2020 08:15:34 -0500 Received: from unicorn.mansr.com ([81.2.72.234]:59632 "EHLO unicorn.mansr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726105AbgCGNPe (ORCPT ); Sat, 7 Mar 2020 08:15:34 -0500 X-Greylist: delayed 437 seconds by postgrey-1.27 at vger.kernel.org; Sat, 07 Mar 2020 08:15:34 EST Received: by unicorn.mansr.com (Postfix, from userid 51770) id 165E615F0E; Sat, 7 Mar 2020 13:08:16 +0000 (GMT) From: Mans Rullgard To: Bin Liu Cc: Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] usb: musb: fix crash with highmen PIO and usbmon Date: Sat, 7 Mar 2020 13:07:20 +0000 Message-Id: <20200307130720.16652-1-mans@mansr.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org When handling a PIO bulk transfer with highmem buffer, a temporary mapping is assigned to urb->transfer_buffer. After the transfer is complete, an invalid address is left behind in this pointer. This is not ordinarily a problem since nothing touches that buffer before the urb is released. However, when usbmon is active, usbmon_urb_complete() calls (indirectly) mon_bin_get_data() which does access the transfer buffer if it is set. To prevent an invalid memory access here, reset urb->tranfer_buffer to NULL when finished. Fixes: 8e8a55165469 ("usb: musb: host: Handle highmem in PIO mode") Signed-off-by: Mans Rullgard --- drivers/usb/musb/musb_host.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c index 1c813c37462a..b67b40de1947 100644 --- a/drivers/usb/musb/musb_host.c +++ b/drivers/usb/musb/musb_host.c @@ -1459,8 +1459,10 @@ void musb_host_tx(struct musb *musb, u8 epnum) qh->segsize = length; if (qh->use_sg) { - if (offset + length >= urb->transfer_buffer_length) + if (offset + length >= urb->transfer_buffer_length) { qh->use_sg = false; + urb->transfer_buffer = NULL; + } } musb_ep_select(mbase, epnum); @@ -1977,8 +1979,10 @@ void musb_host_rx(struct musb *musb, u8 epnum) urb->actual_length += xfer_len; qh->offset += xfer_len; if (done) { - if (qh->use_sg) + if (qh->use_sg) { qh->use_sg = false; + urb->transfer_buffer = NULL; + } if (urb->status == -EINPROGRESS) urb->status = status; -- 2.25.1