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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 06880C33CB1 for ; Wed, 15 Jan 2020 09:41:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C5F9C24671 for ; Wed, 15 Jan 2020 09:41:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579081309; bh=/aX3309DkEg99Z/qlmZBeVRGZgtaUe+Zr8M2UZjMcsE=; h=Subject:To:From:Date:List-ID:From; b=FXMGtpj1WcKmaumVO7HVj3MtTTwA92usAL0jbdiMKsMwrpHd85S67CSpz1BC7Jjm9 5Xs3yqaw+K0VTm5YW2TC4UJjicVlBuFOV1z78bbc+G/fZMeb6ZKUc4te3eSJy9bfej XK/Sla+Lkc31cmg8FbQdB+xB263HbT0sRRxujXDE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729462AbgAOJlt (ORCPT ); Wed, 15 Jan 2020 04:41:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:43052 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729143AbgAOJlt (ORCPT ); Wed, 15 Jan 2020 04:41:49 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CBB0C24671; Wed, 15 Jan 2020 09:41:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579081308; bh=/aX3309DkEg99Z/qlmZBeVRGZgtaUe+Zr8M2UZjMcsE=; h=Subject:To:From:Date:From; b=Q+hi9qEBdnQJY1XVLgfx9grVR4A+WdcrrVwf9OkTbajCkijRy2mGypXUOy0juTajr f42K1mll38IZCvVNWCQDljAszZ4ifjG2b9Nam6A9C9GSf8pbfV2/3NcpWXLLAFUSIT ppTDvqSbzxpKtJnUcV+s/ArIPVoaSjW1IlpxwiKE= Subject: patch "usb: gadget: f_ncm: Use atomic_t to track in-flight request" added to usb-testing To: bryan.odonoghue@linaro.org, balbi@kernel.org, gregkh@linuxfoundation.org, stable@vger.kernel.org From: Date: Wed, 15 Jan 2020 10:41:09 +0100 Message-ID: <15790812697392@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled usb: gadget: f_ncm: Use atomic_t to track in-flight request to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-testing branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will be merged to the usb-next branch sometime soon, after it passes testing, and the merge window is open. If you have any questions about this process, please let me know. >From 5b24c28cfe136597dc3913e1c00b119307a20c7e Mon Sep 17 00:00:00 2001 From: Bryan O'Donoghue Date: Thu, 9 Jan 2020 13:17:21 +0000 Subject: usb: gadget: f_ncm: Use atomic_t to track in-flight request Currently ncm->notify_req is used to flag when a request is in-flight. ncm->notify_req is set to NULL and when a request completes it is subsequently reset. This is fundamentally buggy in that the unbind logic of the NCM driver will unconditionally free ncm->notify_req leading to a NULL pointer dereference. Fixes: 40d133d7f542 ("usb: gadget: f_ncm: convert to new function interface with backward compatibility") Cc: stable Signed-off-by: Bryan O'Donoghue Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_ncm.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c index 2d6e76e4cffa..1d900081b1f0 100644 --- a/drivers/usb/gadget/function/f_ncm.c +++ b/drivers/usb/gadget/function/f_ncm.c @@ -53,6 +53,7 @@ struct f_ncm { struct usb_ep *notify; struct usb_request *notify_req; u8 notify_state; + atomic_t notify_count; bool is_open; const struct ndp_parser_opts *parser_opts; @@ -547,7 +548,7 @@ static void ncm_do_notify(struct f_ncm *ncm) int status; /* notification already in flight? */ - if (!req) + if (atomic_read(&ncm->notify_count)) return; event = req->buf; @@ -587,7 +588,8 @@ static void ncm_do_notify(struct f_ncm *ncm) event->bmRequestType = 0xA1; event->wIndex = cpu_to_le16(ncm->ctrl_id); - ncm->notify_req = NULL; + atomic_inc(&ncm->notify_count); + /* * In double buffering if there is a space in FIFO, * completion callback can be called right after the call, @@ -597,7 +599,7 @@ static void ncm_do_notify(struct f_ncm *ncm) status = usb_ep_queue(ncm->notify, req, GFP_ATOMIC); spin_lock(&ncm->lock); if (status < 0) { - ncm->notify_req = req; + atomic_dec(&ncm->notify_count); DBG(cdev, "notify --> %d\n", status); } } @@ -632,17 +634,19 @@ static void ncm_notify_complete(struct usb_ep *ep, struct usb_request *req) case 0: VDBG(cdev, "Notification %02x sent\n", event->bNotificationType); + atomic_dec(&ncm->notify_count); break; case -ECONNRESET: case -ESHUTDOWN: + atomic_set(&ncm->notify_count, 0); ncm->notify_state = NCM_NOTIFY_NONE; break; default: DBG(cdev, "event %02x --> %d\n", event->bNotificationType, req->status); + atomic_dec(&ncm->notify_count); break; } - ncm->notify_req = req; ncm_do_notify(ncm); spin_unlock(&ncm->lock); } @@ -1649,6 +1653,11 @@ static void ncm_unbind(struct usb_configuration *c, struct usb_function *f) ncm_string_defs[0].id = 0; usb_free_all_descriptors(f); + if (atomic_read(&ncm->notify_count)) { + usb_ep_dequeue(ncm->notify, ncm->notify_req); + atomic_set(&ncm->notify_count, 0); + } + kfree(ncm->notify_req->buf); usb_ep_free_request(ncm->notify, ncm->notify_req); } -- 2.24.1