From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 B84F43C3C1C; Sat, 30 May 2026 18:30:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780165856; cv=none; b=XyzkivBXP06YECwmJlGDoXj+kEQXfGtSiOdhtI+nDb2vStEXDvh8bDIDhFo4ZMJP1P21Ikitwd7x6JtJaww1IFYpiQpK1/ILkGsjfDB/N9Bu0v3lyxFWQWuaGfYTpqjAmhM/cfxhofTR1y//GPUXKk8Mt1B5UfkMYOMcv0XyIaQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780165856; c=relaxed/simple; bh=sxcVWK4ILmVi21rYih05Al4VZfeVHKvMTo+CVcQxFbI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=az7v2izf44IwjKLswscEXsmybxCskyWbi7145n7a52l85MWQj0ifkPPvsFlzTOpoK8BDB7wePrkz0AfdeTrX6gO9vUmVLdL6xsvdZwfCiwzmssVYLvVGFlzXBlMcaojI5pYbW3S2+xniXoGyAHT1EgUU6MlvDlvW23UuXi2aBIk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=sbKOvMS/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="sbKOvMS/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 096B31F00893; Sat, 30 May 2026 18:30:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780165855; bh=CMMdsZOzHn48FvjVzdT9i61zponJcY2r7PIBF0mffPE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=sbKOvMS/YqIu35bhNxlsLGIA58CObMyW8SOvDv7m7T+rmeYW57suHLKwe5kSvXvY9 usWdq6SvPEI//EwGt1zgVgOJV9l3rg+qA6PMJcIEeD76/BVa4oZOPBkW02KnQXqnlD mPVbK0dqqhqJyyJUJTYJe5x1jzF1qpuV1GIuwOCc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+2afd7e71155c7e241560@syzkaller.appspotmail.com, Deepanshu Kartikey , Takashi Iwai Subject: [PATCH 5.10 202/589] ALSA: caiaq: fix usb_dev refcount leak on probe failure Date: Sat, 30 May 2026 18:01:23 +0200 Message-ID: <20260530160230.237906585@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160224.570625122@linuxfoundation.org> References: <20260530160224.570625122@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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Deepanshu Kartikey commit 7a5f1cd22d47f8ca4b760b6334378ae42c1bd24b upstream. create_card() takes a reference on the USB device with usb_get_dev() and stores the matching usb_put_dev() in card_free(), which is installed as the snd_card's ->private_free destructor. However, ->private_free is only assigned near the end of init_card(), after several failure points (usb_set_interface(), EP type checks, usb_submit_urb(), the EP1_CMD_GET_DEVICE_INFO exchange, and its timeout). When any of those fail, init_card() returns an error to snd_probe(), which calls snd_card_free(card). Because ->private_free is still NULL, card_free() never runs, the usb_get_dev() reference is not dropped, and the struct usb_device leaks along with its descriptor allocations and device_private. syzbot reproduces this with a malformed UAC3 device whose only valid altsetting is 0; init_card()'s usb_set_interface(usb_dev, 0, 1) call fails with -EIO and triggers the leak. Move the ->private_free assignment into create_card(), immediately after usb_get_dev(), so that every error path reaching snd_card_free() balances the reference. card_free()'s callees (snd_usb_caiaq_input_free, free_urbs, kfree) already tolerate the partially-initialized state because the chip private area is zero-initialized by snd_card_new(). Fixes: 80bb50e2d459 ("ALSA: caiaq: take a reference on the USB device in create_card()") Reported-by: syzbot+2afd7e71155c7e241560@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=2afd7e71155c7e241560 Tested-by: syzbot+2afd7e71155c7e241560@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Deepanshu Kartikey Link: https://patch.msgid.link/20260426001934.70813-1-kartikey406@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/caiaq/device.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/sound/usb/caiaq/device.c +++ b/sound/usb/caiaq/device.c @@ -437,6 +437,7 @@ static int create_card(struct usb_device cdev = caiaqdev(card); cdev->chip.dev = usb_get_dev(usb_dev); + card->private_free = card_free; cdev->chip.card = card; cdev->chip.usb_id = USB_ID(le16_to_cpu(usb_dev->descriptor.idVendor), le16_to_cpu(usb_dev->descriptor.idProduct)); @@ -525,7 +526,6 @@ static int init_card(struct snd_usb_caia snprintf(card->longname, sizeof(card->longname), "%s %s (%s)", cdev->vendor_name, cdev->product_name, usbpath); - card->private_free = card_free; err = setup_card(cdev); if (err < 0) goto err_kill_urb;