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 F2A5513AD3F; Sat, 19 Jul 2025 06:56:52 +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=1752908213; cv=none; b=M+sLl1gKGlAvsfp8ZRjpVt+3G/MfLbt0w+OBBX6UHZNdIaN/XirgWxAxgErutASquVO3snPq3U7shV2MGp0vZxKM2bafir8TNiiQr0KZQlCa7GaHt+C8w1q6kX055o7X58QcxDbNi5s+1D+BwODmehRzv970uBMwmvGlv51UKOY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752908213; c=relaxed/simple; bh=r6bw3423e8YmtqggTsK4AedE2im5LHqew1In59FP+cM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=CdqWOBllK9dCyJ/u3sl9lj+Nvl495zlvx/uUdIZmlKA2GyL/Hjj7E5r+S5+Sf6MT6dGbJk18bDVnuZK73W8o1YhY/FKjiecg8oPe6MYJvT3Oul0sVRct87CXwKpUe3APba2C1T26+cBTrhgyYV0Y3XXcr1r1SjbGuzdZ1Vvs7KM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=v6f7DdJK; 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="v6f7DdJK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 046F2C4CEE3; Sat, 19 Jul 2025 06:56:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1752908212; bh=r6bw3423e8YmtqggTsK4AedE2im5LHqew1In59FP+cM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=v6f7DdJKgdJuivI7S1S/mCg1pPwsQ8aB7Cu34YiEF3mykd67v0WUibsLotqpEP3TM cLOWc3VvGSR5aXI2wsTYDv0uw6F/TrGknofh05Ow7XQ5+S8J9mTIVJLApOesyWwQ7A nu82/yCcF1IoeXR2KyPdhsERK/6i9LnKTaTop5AA= Date: Sat, 19 Jul 2025 08:56:49 +0200 From: Greg KH To: Tao Xue Cc: Thinh.Nguyen@synopsys.com, prashanth.k@oss.qualcomm.com, m.grzeschik@pengutronix.de, Chris.Wulff@biamp.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, caiyadong@huawei.com, suzhuangluan@hisilicon.com, weiwenwen3@huawei.com Subject: Re: [PATCH] usb: gadget : fix use-after-free in composite_dev_cleanup() Message-ID: <2025071946-dilation-elongated-b68f@gregkh> References: <20250719045612.10739-1-xuetao09@huawei.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250719045612.10739-1-xuetao09@huawei.com> On Sat, Jul 19, 2025 at 12:56:12PM +0800, Tao Xue wrote: > The pointer cdev->os_desc_req need to be set null when kmalloc failed in > composite_os_desc_req_prepare(),otherwise the use-after-free issue will > be encountered in composite_dev_cleanup() > > BUG: KASAN: use-after-free in composite_dev_cleanup+0xf4/0x2c0 > Read of size 8 at addr 0000004827837a00 by task init/1 > > CPU: 10 PID: 1 Comm: init Tainted: G O 5.10.97-oh #1 > kasan_report+0x188/0x1cc > __asan_load8+0xb4/0xbc > composite_dev_cleanup+0xf4/0x2c0 > configfs_composite_bind+0x210/0x7ac > udc_bind_to_driver+0xb4/0x1ec > usb_gadget_probe_driver+0xec/0x21c > gadget_dev_desc_UDC_store+0x264/0x27c > > Fixes: 37a3a533429e ("usb: gadget: OS Feature Descriptors support") > Signed-off-by: Tao Xue > Signed-off-by: weiwenwen The order of signed-off-by is odd here. And I need a "full" name for the last one please. > --- > drivers/usb/gadget/composite.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c > index 8dbc132a505e..385398a039ea 100644 > --- a/drivers/usb/gadget/composite.c > +++ b/drivers/usb/gadget/composite.c > @@ -2489,6 +2489,7 @@ int composite_os_desc_req_prepare(struct usb_composite_dev *cdev, > if (!cdev->os_desc_req->buf) { > ret = -ENOMEM; > usb_ep_free_request(ep0, cdev->os_desc_req); > + cdev->os_desc_req = NULL; Can you add a comment here as to why you need to set this to NULL, as it is not obvious at all. thanks, greg k-h