From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B75A23290A5; Fri, 24 Apr 2026 13:40:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777038045; cv=none; b=W25gZnMzM+wwaHQrnX0TQpLbZL9iMK9x1F9fSnB2nDFkh4HWAwSlMLKmP0GM/qFpNZ37kJUGHQaWsN2yX9o0fvdHUtE+Xk03uowntbmjYFaJGTaRa4t6IEn0ExwnKHJxHzh2uZ+H/6hNzTsA/2Flk9m8dq+KXABivMHcPAQYaic= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777038045; c=relaxed/simple; bh=alJDQ/T3ghPjNNkE8xR6G9UgQfDQxIVxi01TUX8qPW0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=M2+iMRDtP8c9Ksb7doXi3y/F0xclR+7ItqCwinIeK0jGuoQ8QkZlidbo0B4FoMvGrR3vn6VM7JO/gXfjZXJEptswqPdu1ArL19wktb6kOrW6jfvioOjpZ50PlHLimwAXMLN1LW/oYvJgXKGk5mNT4HEKnd2INcs3E98xd/thaHI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Id3EAtiX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Id3EAtiX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 07E20C19425; Fri, 24 Apr 2026 13:40:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1777038045; bh=alJDQ/T3ghPjNNkE8xR6G9UgQfDQxIVxi01TUX8qPW0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Id3EAtiXlD6BXbjLYG//BBQAqPdyaaKMkav2MB1XNDnGv74A+8erOqGn4c+O1XJS0 +AG8GSUAwxsLa99m52ghW0TEX8+uhcK+okcbwGW6GzC+9QInPf8raxe3XdRj63h8Tj GenTguibK83MKlpHbjNWZiUYs70VfF1eglvO4Tuw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Andrey Konovalov , Berk Cem Goksel , Takashi Iwai Subject: [PATCH 6.6 158/166] ALSA: caiaq: take a reference on the USB device in create_card() Date: Fri, 24 Apr 2026 15:31:12 +0200 Message-ID: <20260424132606.132598371@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260424132532.812258529@linuxfoundation.org> References: <20260424132532.812258529@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Berk Cem Goksel commit 80bb50e2d459213cccff3111d5ef98ed4238c0d5 upstream. The caiaq driver stores a pointer to the parent USB device in cdev->chip.dev but never takes a reference on it. The card's private_free callback, snd_usb_caiaq_card_free(), can run asynchronously via snd_card_free_when_closed() after the USB device has already been disconnected and freed, so any access to cdev->chip.dev in that path dereferences a freed usb_device. On top of the refcounting issue, the current card_free implementation calls usb_reset_device(cdev->chip.dev). A reset in a free callback is inappropriate: the device is going away, the call takes the device lock in a teardown context, and the reset races with the disconnect path that the callback is already cleaning up after. Take a reference on the USB device in create_card() with usb_get_dev(), drop it with usb_put_dev() in the free callback, and remove the usb_reset_device() call. Fixes: b04dcbb7f7b1 ("ALSA: caiaq: Use snd_card_free_when_closed() at disconnection") Cc: stable@vger.kernel.org Cc: Andrey Konovalov Signed-off-by: Berk Cem Goksel Link: https://patch.msgid.link/20260413034941.1131465-3-berkcgoksel@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/caiaq/device.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/sound/usb/caiaq/device.c +++ b/sound/usb/caiaq/device.c @@ -384,7 +384,7 @@ static void card_free(struct snd_card *c snd_usb_caiaq_input_free(cdev); #endif snd_usb_caiaq_audio_free(cdev); - usb_reset_device(cdev->chip.dev); + usb_put_dev(cdev->chip.dev); } static int create_card(struct usb_device *usb_dev, @@ -410,7 +410,7 @@ static int create_card(struct usb_device return err; cdev = caiaqdev(card); - cdev->chip.dev = usb_dev; + cdev->chip.dev = usb_get_dev(usb_dev); cdev->chip.card = card; cdev->chip.usb_id = USB_ID(le16_to_cpu(usb_dev->descriptor.idVendor), le16_to_cpu(usb_dev->descriptor.idProduct));