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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 C532EC433E2 for ; Thu, 18 Jun 2020 01:38:32 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 52DD122208 for ; Thu, 18 Jun 2020 01:38:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="H0Sd0A/r"; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="eItFGNVl" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 52DD122208 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 7831816FD; Thu, 18 Jun 2020 03:37:40 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 7831816FD DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1592444310; bh=Xwqp5VeiNd1IsDMeWotZ1nD25aou2uHxHhgfdlOCxX8=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=H0Sd0A/rk5Qjj8mOkiv+EZB7AXDsDVhUzVJ1i38OQuIxj9W4QgATN+w7uh0BjO/9G +rsKiXajtjwpA6l4pBFqIhDOO6k6LF8Zqi5HHBAfPZ2aHkaMJ229WGN92pS3Q2Nq22 oqMdgI3uuhmT3NVft9fgyEmEimDbSFqU42gMln0w= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 474C0F8046E; Thu, 18 Jun 2020 03:18:57 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 829D7F80459; Thu, 18 Jun 2020 03:18:54 +0200 (CEST) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id BB6AFF80338 for ; Thu, 18 Jun 2020 03:18:50 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz BB6AFF80338 Authentication-Results: alsa1.perex.cz; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="eItFGNVl" Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D061B21D90; Thu, 18 Jun 2020 01:18:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592443129; bh=Xwqp5VeiNd1IsDMeWotZ1nD25aou2uHxHhgfdlOCxX8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eItFGNVlcsJB1ZSKxRnTteOHwGu2lLIVvQDRlHRy97OZdwzNRKf74+5ztj1wvgXKR FdtE+2BBdEGPR5o4jnXzVHqfuANZEwG+B87nvLfoXprkGZEsThrJfbf1K3xxFQijnP s5S5O6GbQ/FRfcHrYzfbhy1cFD15CDi2cGbq3mZk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 102/266] ALSA: usb-audio: Fix racy list management in output queue Date: Wed, 17 Jun 2020 21:13:47 -0400 Message-Id: <20200618011631.604574-102-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200618011631.604574-1-sashal@kernel.org> References: <20200618011631.604574-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Cc: Takashi Iwai , Sasha Levin , alsa-devel@alsa-project.org X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" From: Takashi Iwai [ Upstream commit 5b6cc38f3f3f37109ce72b60bda215a5f6892c0b ] The linked list entry from FIFO is peeked at queue_pending_output_urbs() but the actual element pop-out is performed outside the spinlock, and it's potentially racy. Do delete the link at the right place inside the spinlock. Fixes: 8fdff6a319e7 ("ALSA: snd-usb: implement new endpoint streaming model") Link: https://lore.kernel.org/r/20200424074016.14301-1-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/usb/endpoint.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index d8dc7cb56d43..50104f658ed4 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -346,17 +346,17 @@ static void queue_pending_output_urbs(struct snd_usb_endpoint *ep) ep->next_packet_read_pos %= MAX_URBS; /* take URB out of FIFO */ - if (!list_empty(&ep->ready_playback_urbs)) + if (!list_empty(&ep->ready_playback_urbs)) { ctx = list_first_entry(&ep->ready_playback_urbs, struct snd_urb_ctx, ready_list); + list_del_init(&ctx->ready_list); + } } spin_unlock_irqrestore(&ep->lock, flags); if (ctx == NULL) return; - list_del_init(&ctx->ready_list); - /* copy over the length information */ for (i = 0; i < packet->packets; i++) ctx->packet_size[i] = packet->packet_size[i]; -- 2.25.1