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 9677D3D75D9; Fri, 24 Apr 2026 13:44:21 +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=1777038261; cv=none; b=EwYNhx3pb1gcB8hTX93dTB7kELu5Gz0n2Dle3laHy+/YUzsCEVu3zGXurvy6XfBaBFMKXjAOmQHZk/6Ub6HyjbpvVwQY3aqsdsaGigzElCTk98mvLOa0dUTKHWjr0GkK8ImuU2dxg98uMiIxBIjvhcO9vnfnH4vrnAcMpVtDEjE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777038261; c=relaxed/simple; bh=9Y933KnfbHMy3juAdJyeA80xi9ebUpk9OXZvo+ZppPU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=N4Po5TQ433iuXv2iGJZrybek4GvxLIyNsWnnpz4Ol8gJ5xtg43TqKKhQkqyx06apUuGiGkufOzXV+Icoah4bCCEJSCZLqoaukqBZzaLigccYE/CdR5R0V93M/TIbT5TiAD/LWg1m3Pk7NkR8kcaf6YHh51FwRkoDU7zqCDFM04E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=KHmCZ5yO; 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="KHmCZ5yO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2ED45C19425; Fri, 24 Apr 2026 13:44:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1777038261; bh=9Y933KnfbHMy3juAdJyeA80xi9ebUpk9OXZvo+ZppPU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KHmCZ5yOUlTO4K1H3UOUi2SKBkYzSfQdNDN6mGeGOOdgQvi/bxK8O/qVpf1v14w1g 3hb0kleplix95FyEG5cV9viKy1uHo1hmphkEx1rKvqZvwaPHAT83Mr8z555ndaj/wy qqP1rLdR/5Zx5/6YFMqyN09cdSn+1fx+Ye1LSbag= 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 6.12 30/35] ALSA: caiaq: take a reference on the USB device in create_card() Date: Fri, 24 Apr 2026 15:31:37 +0200 Message-ID: <20260424132418.090438321@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260424132411.427029259@linuxfoundation.org> References: <20260424132411.427029259@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 6.12-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));