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 1629427466A for ; Tue, 7 Jul 2026 05:58:50 +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=1783403932; cv=none; b=VNTBvjdNyAqbO2MtRojL1exfzhUoiiym3OU2/inupwJdL0mY/SO1se9hY1gZxjmfdgIw7O1Kl04nBWaV8FGT2qyGwQ/qSPgGrbWhs73bbJ3eZwjD1FeBMODDrsJjNG7VyDLPDPWBJpJHXehU/+Zi8vvyzrV2KD3RhqMFCzMIyus= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783403932; c=relaxed/simple; bh=iqidT9IDQi3JPjoHd2ejPJaUNZLao120O8mmi/giSnM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Q2NaoGxOh+Q3kBm86RBjBl3Suen8Y6wwrZ3J3PJfbMSNlHqEe22EDRy2ymjzO0+LxT/NDy5ntmpkl67Tz+BI8nVEwsA0d4MOdir+0OXOJmN0ldHnLdAeSXTh2zdRT0S9d1kQMRnswCWWzB6kfDAcHhfxEGZDZfGSfgytP4OEL7A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=LizRrqQk; 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="LizRrqQk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EB5861F000E9; Tue, 7 Jul 2026 05:58:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1783403930; bh=2SjRVV0YM5ftwKXtXC/stGCA7doFGhrJJerQzxnzOCo=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=LizRrqQkCS1MB4zZcsvzLNfImS9/k8Z0v1Q853/8aIvqh8W5c2zQBWAGfdYe43x3c 5bMoJcSH1zKBOaQAhCsFbEjvQdC8q6EVDEgGmh4y5NQi7MWlxKKkbdv/VwhngSPB3G TWhU6st/nkB4A/f+z3O3kit2Kaf+Y0weZjYCssuY= Date: Tue, 7 Jul 2026 07:59:03 +0200 From: Greg KH To: "Dynetrex, Admin" Cc: linux-can@vger.kernel.org, peter_hong@fintek.com.tw, mkl@pengutronix.de, mailhol@kernel.org, stable@kernel.org Subject: Re: [REGRESSION] can: usb: f81604: TX broken with "short int URB: 9 < 12" Message-ID: <2026070732-reformer-civil-a4d8@gregkh> References: Precedence: bulk X-Mailing-List: linux-can@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: On Mon, Jul 06, 2026 at 10:46:00PM -0700, Dynetrex, Admin wrote: > Hello, > > I found an issue with a patch applied to the can/usb/f81604 driver on 2026-02-23. > > https://git.kernel.org/stable/c/36ead57443146e6b730ce1f48ca3e9b17e19a3d2 > > The patch added a check to make sure urb->actual_length is not less than sizeof(struct f81604_int_data). The issue is that the interrupt data from the device is 9 bytes, but sizeof(struct f81604_int_data) returns 12 because the struct is marked __aligned(4). > > This causes valid interrupt URBs to be rejected. After this patch, CAN frames no longer transmit successfully, while before the patch they transmitted without issue. > > Each transmit attempt logs the following in dmesg: > > f81604_read_int_callback: short int URB: 9 < 12 > > Please consider either removing the __aligned(4) attribute from struct f81604_int_data, or using a constant for the actual wire packet length when checking urb->actual_length. Please consider submitting a patch to resolve this issue so you get full credit for the fix. thanks, greg k-h