From patchwork Thu May 12 12:37:22 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oliver Neukum X-Patchwork-Id: 12847655 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4760AC433F5 for ; Thu, 12 May 2022 12:37:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353863AbiELMhb (ORCPT ); Thu, 12 May 2022 08:37:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353756AbiELMh1 (ORCPT ); Thu, 12 May 2022 08:37:27 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D178662136 for ; Thu, 12 May 2022 05:37:26 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 8F4D521C82; Thu, 12 May 2022 12:37:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1652359045; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=L7b9NWV1Di5pSPdF/xuUrWQE6D56vC/QzYoNJmH9wT4=; b=vWoKwF800Vx/k/7F5layi9MYYFCtRK+d5yIeHn1qsX9EaRpEICK6Ugv08vaMFu/fITPvqD jW6NIEQPQuUHxxbusi+HNOTKAhfe1uoFvXoDw9mXWShVj3gNRPgJzqw5xBA9nPNJzg3xCZ sOX+rxkPqWQoKsWDzBXjovftVPrp4hw= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 5F05713ABE; Thu, 12 May 2022 12:37:25 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id QCSQFYX/fGL/GgAAMHmgww (envelope-from ); Thu, 12 May 2022 12:37:25 +0000 From: Oliver Neukum To: linux-media@vger.kernel.org, mchehab@kernel.org, sean@mess.org Cc: Oliver Neukum Subject: [PATCHv2 3/4] igorplugusb: break cyclical race on disconnect Date: Thu, 12 May 2022 14:37:22 +0200 Message-Id: <20220512123723.25815-3-oneukum@suse.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20220512123723.25815-1-oneukum@suse.com> References: <20220512123723.25815-1-oneukum@suse.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The driver uses a timer, that may submit the URB and the URB may start the timer. No simple order of killing can break te cycle. Poison the URB before killing the timer. v2: Resending series due to omitting first patch Signed-off-by: Oliver Neukum --- drivers/media/rc/igorplugusb.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/media/rc/igorplugusb.c b/drivers/media/rc/igorplugusb.c index 1afba95409ff..b2245849f7aa 100644 --- a/drivers/media/rc/igorplugusb.c +++ b/drivers/media/rc/igorplugusb.c @@ -126,7 +126,7 @@ static void igorplugusb_cmd(struct igorplugusb *ir, int cmd) ir->request.bRequest = cmd; ir->urb->transfer_flags = 0; ret = usb_submit_urb(ir->urb, GFP_ATOMIC); - if (ret) + if (ret && ret != -EPERM) dev_err(ir->dev, "submit urb failed: %d", ret); } @@ -223,7 +223,9 @@ static int igorplugusb_probe(struct usb_interface *intf, return 0; fail: + usb_poison_urb(ir->urb); del_timer(&ir->timer); + usb_unpoison_urb(ir->urb); usb_free_urb(ir->urb); rc_free_device(ir->rc); kfree(ir->buf_in); @@ -236,9 +238,10 @@ static void igorplugusb_disconnect(struct usb_interface *intf) struct igorplugusb *ir = usb_get_intfdata(intf); rc_unregister_device(ir->rc); + usb_poison_urb(ir->urb); del_timer_sync(&ir->timer); usb_set_intfdata(intf, NULL); - usb_kill_urb(ir->urb); + usb_unpoison_urb(ir->urb); usb_free_urb(ir->urb); kfree(ir->buf_in); }