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[23.128.96.34]) by mx.google.com with ESMTPS id eg21-20020a056a00801500b0068fb9ef97fbsi5058589pfb.200.2023.09.16.07.44.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 16 Sep 2023 07:44:26 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) client-ip=23.128.96.34; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b="i//bJjHl"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by howler.vger.email (Postfix) with ESMTP id EDDE7867F1D9; Mon, 11 Sep 2023 21:50:49 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at howler.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231675AbjILETn (ORCPT + 40 others); Tue, 12 Sep 2023 00:19:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232391AbjILETj (ORCPT ); Tue, 12 Sep 2023 00:19:39 -0400 Received: from mail-pg1-x54a.google.com (mail-pg1-x54a.google.com [IPv6:2607:f8b0:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97CA81BE for ; Mon, 11 Sep 2023 21:19:35 -0700 (PDT) Received: by mail-pg1-x54a.google.com with SMTP id 41be03b00d2f7-56c556b5aceso6906972a12.1 for ; Mon, 11 Sep 2023 21:19:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1694492375; x=1695097175; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=NUt0ePSVkhiVTD3YqchYHP4wGyuRh1Xi9jvupkBpj0M=; b=i//bJjHlxbhXMfT+5h63w/OTZ6Y6PVvRllKc8UFty5eHzac+RVZ0ktj9M9oWZJxg8o k7GD59TXMAreMqdlqbQ4vuLCIhcWn5/0qlhMf3iePeQKsL5HnwR/wKwv+QL+5pUd4B0j XN3pUL3tDo8C2AsbyDwBCl8xdkj3Ya3dOJ+dQ2rwOKTZ7Je8vDrrxvBqFRj5cSsIxD7W NEZY1FySZlaWMhb7Y8a9qM4W4p6hVahv50aCAH0SDcbURQGmLj9jLebiNlvx/j5Ep4Z3 Aalt4eqA+ggkENhSmlTxyXZoknWMXa1hBqhH+27IGQKR5VkCeFXroKi+SkGEhPBy1cIe KNUg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694492375; x=1695097175; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=NUt0ePSVkhiVTD3YqchYHP4wGyuRh1Xi9jvupkBpj0M=; b=tkfzBGokkoF85J7lxF11lckaQMtjb7zrHEnBmd8guRlG51gnPe4eJG6QP2KNsSOI89 +rG3hdaEu89yQKKydIV8QjVNY6HuyMfzS65CJ7eLmT4TxU3CTTSFzRF4tIh9QrvOnWeV hf52EL55ZnAt/WVmNYUz6iSSqwhzm2J+6mR+JAPGmuRCDerQx4AVQHrUyUd629/jU4A9 7kPdyKumfN+5BgKYyK3Gvky6pjQbgda/bJApdrfXC1QNA6EgvGd4Yg+zkupJsIgtzovU uIs7FD5ao5T1Nio3Ombt1K6+0Ds7kUxOiXr6GN8zzvN2DV8NhVAdkY0oEZ22kVGja5X5 FB6A== X-Gm-Message-State: AOJu0Yz+3JQRJcElhuSM1Yv77aASyS9Ba4xYdEQGbQIp0LQbY5qETmMt aepH4/yHVJwSCJwLvIoCCQQptIeruqZl X-Received: from hi-h2o-specialist.c.googlers.com ([fda3:e722:ac3:cc00:24:72f4:c0a8:3cef]) (user=arakesh job=sendgmr) by 2002:a63:b215:0:b0:577:4510:2391 with SMTP id x21-20020a63b215000000b0057745102391mr1781839pge.12.1694492374822; Mon, 11 Sep 2023 21:19:34 -0700 (PDT) Date: Mon, 11 Sep 2023 21:19:09 -0700 In-Reply-To: <20230912041910.726442-1-arakesh@google.com> Mime-Version: 1.0 References: <20230912041910.726442-1-arakesh@google.com> X-Mailer: git-send-email 2.42.0.283.g2d96d420d3-goog Message-ID: <20230912041910.726442-2-arakesh@google.com> Subject: [PATCH v1 1/2] usb: gadget: uvc: prevent use of disabled endpoint From: Avichal Rakesh To: Laurent Pinchart , Daniel Scally , Greg Kroah-Hartman , Michael Grzeschik Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Avichal Rakesh Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (howler.vger.email [0.0.0.0]); Mon, 11 Sep 2023 21:50:50 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1777205737394280812 X-GMAIL-MSGID: 1777205737394280812 Currently the set_alt callback immediately disables the endpoint and queues the v4l2 streamoff event. However, as the streamoff event is processed asynchronously, it is possible that the video_pump thread attempts to queue requests to an already disabled endpoint. This change moves disabling usb endpoint to the end of streamoff event callback. As the endpoint's state can no longer be used, video_pump is now guarded by uvc->state as well. To be consistent with the actual streaming state, uvc->state is now toggled between CONNECTED and STREAMING from the v4l2 event callback only. Link: https://lore.kernel.org/20230615171558.GK741@pendragon.ideasonboard.com/ Link: https://lore.kernel.org/20230531085544.253363-1-dan.scally@ideasonboard.com/ Signed-off-by: Avichal Rakesh --- drivers/usb/gadget/function/f_uvc.c | 11 +++++------ drivers/usb/gadget/function/f_uvc.h | 2 +- drivers/usb/gadget/function/uvc.h | 2 +- drivers/usb/gadget/function/uvc_v4l2.c | 21 ++++++++++++++++++--- drivers/usb/gadget/function/uvc_video.c | 3 ++- 5 files changed, 27 insertions(+), 12 deletions(-) diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c index faa398109431..75c9f9a3f884 100644 --- a/drivers/usb/gadget/function/f_uvc.c +++ b/drivers/usb/gadget/function/f_uvc.c @@ -263,10 +263,13 @@ uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) return 0; } -void uvc_function_setup_continue(struct uvc_device *uvc) +void uvc_function_setup_continue(struct uvc_device *uvc, int disable_ep) { struct usb_composite_dev *cdev = uvc->func.config->cdev; + if (disable_ep && uvc->video.ep) { + usb_ep_disable(uvc->video.ep); + } usb_composite_setup_continue(cdev); } @@ -337,15 +340,11 @@ uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt) if (uvc->state != UVC_STATE_STREAMING) return 0; - if (uvc->video.ep) - usb_ep_disable(uvc->video.ep); - memset(&v4l2_event, 0, sizeof(v4l2_event)); v4l2_event.type = UVC_EVENT_STREAMOFF; v4l2_event_queue(&uvc->vdev, &v4l2_event); - uvc->state = UVC_STATE_CONNECTED; - return 0; + return USB_GADGET_DELAYED_STATUS; case 1: if (uvc->state != UVC_STATE_CONNECTED) diff --git a/drivers/usb/gadget/function/f_uvc.h b/drivers/usb/gadget/function/f_uvc.h index 1db972d4beeb..e7f9f13f14dc 100644 --- a/drivers/usb/gadget/function/f_uvc.h +++ b/drivers/usb/gadget/function/f_uvc.h @@ -11,7 +11,7 @@ struct uvc_device; -void uvc_function_setup_continue(struct uvc_device *uvc); +void uvc_function_setup_continue(struct uvc_device *uvc, int disale_ep); void uvc_function_connect(struct uvc_device *uvc); diff --git a/drivers/usb/gadget/function/uvc.h b/drivers/usb/gadget/function/uvc.h index 6751de8b63ad..989bc6b4e93d 100644 --- a/drivers/usb/gadget/function/uvc.h +++ b/drivers/usb/gadget/function/uvc.h @@ -177,7 +177,7 @@ struct uvc_file_handle { * Functions */ -extern void uvc_function_setup_continue(struct uvc_device *uvc); +extern void uvc_function_setup_continue(struct uvc_device *uvc, int disable_ep); extern void uvc_function_connect(struct uvc_device *uvc); extern void uvc_function_disconnect(struct uvc_device *uvc); diff --git a/drivers/usb/gadget/function/uvc_v4l2.c b/drivers/usb/gadget/function/uvc_v4l2.c index 3f0a9795c0d4..3d3469883ed0 100644 --- a/drivers/usb/gadget/function/uvc_v4l2.c +++ b/drivers/usb/gadget/function/uvc_v4l2.c @@ -451,7 +451,7 @@ uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type) * Complete the alternate setting selection setup phase now that * userspace is ready to provide video frames. */ - uvc_function_setup_continue(uvc); + uvc_function_setup_continue(uvc, 0); uvc->state = UVC_STATE_STREAMING; return 0; @@ -463,11 +463,19 @@ uvc_v4l2_streamoff(struct file *file, void *fh, enum v4l2_buf_type type) struct video_device *vdev = video_devdata(file); struct uvc_device *uvc = video_get_drvdata(vdev); struct uvc_video *video = &uvc->video; + int ret = 0; if (type != video->queue.queue.type) return -EINVAL; - return uvcg_video_enable(video, 0); + uvc->state = UVC_STATE_CONNECTED; + ret = uvcg_video_enable(video, 0); + if (ret < 0) { + return ret; + } + + uvc_function_setup_continue(uvc, 1); + return 0; } static int @@ -500,6 +508,14 @@ uvc_v4l2_subscribe_event(struct v4l2_fh *fh, static void uvc_v4l2_disable(struct uvc_device *uvc) { uvc_function_disconnect(uvc); + if (uvc->state == UVC_STATE_STREAMING) { + /* + * Drop uvc->state to CONNECTED if it was streaming before. + * This ensures that the usb_requests are no longer queued + * to the controller. + */ + uvc->state = UVC_STATE_CONNECTED; + } uvcg_video_enable(&uvc->video, 0); uvcg_free_buffers(&uvc->video.queue); uvc->func_connected = false; @@ -647,4 +663,3 @@ const struct v4l2_file_operations uvc_v4l2_fops = { .get_unmapped_area = uvcg_v4l2_get_unmapped_area, #endif }; - diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c index 91af3b1ef0d4..70ff88854539 100644 --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -382,6 +382,7 @@ static void uvcg_video_pump(struct work_struct *work) { struct uvc_video *video = container_of(work, struct uvc_video, pump); struct uvc_video_queue *queue = &video->queue; + struct uvc_device *uvc = video->uvc; /* video->max_payload_size is only set when using bulk transfer */ bool is_bulk = video->max_payload_size; struct usb_request *req = NULL; @@ -390,7 +391,7 @@ static void uvcg_video_pump(struct work_struct *work) bool buf_done; int ret; - while (video->ep->enabled) { + while (uvc->state == UVC_STATE_STREAMING && video->ep->enabled) { /* * Retrieve the first available USB request, protected by the * request lock. 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[23.128.96.37]) by mx.google.com with ESMTPS id f16-20020a056a00229000b0068e45c9c986si7848093pfe.136.2023.09.11.23.04.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Sep 2023 23:04:16 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) client-ip=23.128.96.37; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20230601 header.b=m01Afecu; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 0277B81A7AE8; Mon, 11 Sep 2023 21:50:50 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.8 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232394AbjILETw (ORCPT + 40 others); Tue, 12 Sep 2023 00:19:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232146AbjILETp (ORCPT ); Tue, 12 Sep 2023 00:19:45 -0400 Received: from mail-pl1-x649.google.com (mail-pl1-x649.google.com [IPv6:2607:f8b0:4864:20::649]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0C7C7E64 for ; Mon, 11 Sep 2023 21:19:38 -0700 (PDT) Received: by mail-pl1-x649.google.com with SMTP id d9443c01a7336-1bf60f85d78so73910595ad.3 for ; Mon, 11 Sep 2023 21:19:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1694492377; x=1695097177; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=3FoTtHZn5McnPgtWNsfVZSyVXUY1RZpX9ounYkXsDLo=; b=m01Afecuhy9AK3GxxTyUuPvu74pfp2YF5BpLxhxSTCguBgYu9/ZbTxh3cRWhTBfUbb d481CrU/dV0gARnOvAYUDAN/h3YN6vfizBcQv194JXZdOP2H3gee98/hLKPom8RsHfE0 e9fCzHuAbchc62yUbTiOJ1mwklZMWsF9aEhl7qUQS55CQrKCs4w5MEOokhSWhKZFRVs8 RyssCBzXxrJd2Z2bw0Yr4JL9z8kxaFKDU/6XeiYH9LufPuwBwCm3WSMlIrWsObnhXSsN byR79q4iSenoZHcQw3nZmgD313yu6HeZ49DV3zVdCBamw3jZw2um1w5nlsSi/cGPtZrY ngPA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694492377; x=1695097177; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=3FoTtHZn5McnPgtWNsfVZSyVXUY1RZpX9ounYkXsDLo=; b=Vw+bH/8+swmOP1As6lFVp0p+QFBd6dHGIMzMZuBxCYBWTQhX6b70otS2D+r5GZJ67H ckaEBKDviBS47jxQcqp2vx14VcQBauXTfPjAKm47EEPG/mxh/FGrC7aZ573cZn4+mZqj THkTBw9ejDUaaDtWazSw1CcWoasK4Q2O2lI+W2shcuprWe0Yl/YU+NfLBZ/9w5OqIxET ui8LkYl1Lr8rvP3QsjC0zIRQ1OmeDIyTczavIw6ZvofHgRcfw8xyqiqx357wvN9qmPUV hbj3LCQx1PpWHaB7vvB8RYi6YC/jI4BT6fSULaBef5UsF4K9d54P0lQ/XWF89tsSjUuR PUgA== X-Gm-Message-State: AOJu0YwOjPODUy40bWqpTfYtBpyy10SLPcP4X9zMV9CdsySHJX9RCIaB ilgPDFeHNUdWWF91i/KzpVKT40i5MybE X-Received: from hi-h2o-specialist.c.googlers.com ([fda3:e722:ac3:cc00:24:72f4:c0a8:3cef]) (user=arakesh job=sendgmr) by 2002:a17:902:e808:b0:1bb:de7f:a4b7 with SMTP id u8-20020a170902e80800b001bbde7fa4b7mr4796225plg.10.1694492377612; Mon, 11 Sep 2023 21:19:37 -0700 (PDT) Date: Mon, 11 Sep 2023 21:19:10 -0700 In-Reply-To: <20230912041910.726442-1-arakesh@google.com> Mime-Version: 1.0 References: <20230912041910.726442-1-arakesh@google.com> X-Mailer: git-send-email 2.42.0.283.g2d96d420d3-goog Message-ID: <20230912041910.726442-3-arakesh@google.com> Subject: [PATCH v1 2/2] usb: gadget: uvc: prevent de-allocating inflight usb_requests From: Avichal Rakesh To: Laurent Pinchart , Daniel Scally , Greg Kroah-Hartman , Michael Grzeschik Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Avichal Rakesh Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Mon, 11 Sep 2023 21:50:50 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1776810623544480477 X-GMAIL-MSGID: 1776810623544480477 Currently, when stopping the stream, uvcg_video_enable immediately deallocates the usb_requests after calling usb_ep_dequeue. However, usb_ep_dequeue is asynchronous and it is possible that it deallocates an inflight request. The gadget drivers should wait until the complete callbacks before assuming ownership of the request. This patch adds a simple request counting mechanism to track how many requests are currently owned by the driver. Now when stopping the stream, uvcg_video_enable waits for all the complete callbacks to come through before deallocating the usb_requests. Signed-off-by: Avichal Rakesh --- drivers/usb/gadget/function/uvc.h | 3 +++ drivers/usb/gadget/function/uvc_video.c | 31 ++++++++++++++++++++++++- 2 files changed, 33 insertions(+), 1 deletion(-) -- 2.42.0.283.g2d96d420d3-goog diff --git a/drivers/usb/gadget/function/uvc.h b/drivers/usb/gadget/function/uvc.h index 989bc6b4e93d..e40e702a7074 100644 --- a/drivers/usb/gadget/function/uvc.h +++ b/drivers/usb/gadget/function/uvc.h @@ -104,8 +104,11 @@ struct uvc_video { unsigned int req_size; struct uvc_request *ureq; struct list_head req_free; + unsigned int req_free_count; /* number of requests in req_free */ spinlock_t req_lock; + wait_queue_head_t req_free_queue; + unsigned int req_int_count; void (*encode) (struct usb_request *req, struct uvc_video *video, diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c index 70ff88854539..3ea7d52df80d 100644 --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -284,10 +284,18 @@ uvc_video_complete(struct usb_ep *ep, struct usb_request *req) spin_lock_irqsave(&video->req_lock, flags); list_add_tail(&req->list, &video->req_free); + video->req_free_count++; spin_unlock_irqrestore(&video->req_lock, flags); - if (uvc->state == UVC_STATE_STREAMING) + if (uvc->state == UVC_STATE_STREAMING) { queue_work(video->async_wq, &video->pump); + } else if (video->req_free_count == video->req_size) { + /* + * Wake up thread waiting for all requests to be returned to + * the gadget driver. + */ + wake_up_interruptible(&video->req_free_queue); + } } static int @@ -316,6 +324,7 @@ uvc_video_free_requests(struct uvc_video *video) INIT_LIST_HEAD(&video->req_free); video->req_size = 0; + video->req_free_count = 0; return 0; } @@ -360,6 +369,7 @@ uvc_video_alloc_requests(struct uvc_video *video) } video->req_size = req_size; + video->req_free_count = req_size; /* all requests are currently free */ return 0; @@ -404,6 +414,7 @@ static void uvcg_video_pump(struct work_struct *work) req = list_first_entry(&video->req_free, struct usb_request, list); list_del(&req->list); + video->req_free_count--; spin_unlock_irqrestore(&video->req_lock, flags); /* @@ -480,6 +491,7 @@ static void uvcg_video_pump(struct work_struct *work) spin_lock_irqsave(&video->req_lock, flags); list_add_tail(&req->list, &video->req_free); + video->req_free_count++; spin_unlock_irqrestore(&video->req_lock, flags); return; } @@ -506,6 +518,22 @@ int uvcg_video_enable(struct uvc_video *video, int enable) if (video->ureq && video->ureq[i].req) usb_ep_dequeue(video->ep, video->ureq[i].req); + /* + * Wait 500ms for the usb_requests to be given back to the + * gadget driver. This ensures that we don't accidentally + * reference de-allocated usb_requests in the complete callback. + */ + if (video->req_free_count != video->req_size) { + uvcg_info(&video->uvc->func, + "Waiting 500ms for usb_request complete callbacks.\n"); + ret = wait_event_interruptible_timeout( + video->req_free_queue, + video->req_free_count == video->req_size, + msecs_to_jiffies(500)); + uvcg_info(&video->uvc->func, + "Done waiting for complete callbacks: %d\n", ret); + } + uvc_video_free_requests(video); uvcg_queue_enable(&video->queue, 0); return 0; @@ -538,6 +566,7 @@ int uvcg_video_init(struct uvc_video *video, struct uvc_device *uvc) { INIT_LIST_HEAD(&video->req_free); spin_lock_init(&video->req_lock); + init_waitqueue_head(&video->req_free_queue); INIT_WORK(&video->pump, uvcg_video_pump); /* Allocate a work queue for asynchronous video pump handler. */