From patchwork Thu May 22 06:43:49 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 892118 Received: from mail.zeus03.de (zeus03.de [194.117.254.33]) (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 AFF9F221D9A for ; Thu, 22 May 2025 06:43:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=194.117.254.33 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747896238; cv=none; b=rSZxWauQN89dNirBRd8GD0TGjADwojR9pPCsfYrZyHBTveGyIJHIzJj2ir56XKLZwyZe4DfswGhcOjumxvvCPdVtPJQIgN9PXT46jfKQSfHs2EqApN3JGdT9jyiHn1TFjLA2rV41kiqtYSnivVg8/2iKgagVESo9CvkgEnRHBv8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747896238; c=relaxed/simple; bh=iwosjGa1+dzWBytJRhObLGPI10QCu4QJwWEIdpV9VJo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=FzbVCGuvQTpjBe+6aqSH8bEVIcC9KLuP1pB5fJ4D2WC1LYh4FhzLl7RvC13HEZ6wMALtw663XHeVZZwxyvIPZxp6cagVQGHmzYhn8A96/3HerR6SvekSG/piZwGdRpMAQBqbgampx3CutLrjZQZ9A5xX8H35mlK3nT9xjF7jl/8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sang-engineering.com; spf=pass smtp.mailfrom=sang-engineering.com; dkim=pass (2048-bit key) header.d=sang-engineering.com header.i=@sang-engineering.com header.b=HWRHeBA3; arc=none smtp.client-ip=194.117.254.33 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sang-engineering.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sang-engineering.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=sang-engineering.com header.i=@sang-engineering.com header.b="HWRHeBA3" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= sang-engineering.com; h=from:to:cc:subject:date:message-id :mime-version:content-transfer-encoding; s=k1; bh=z2uDdfs7vPu+Qu xVOd6pqSgCZscHMGXP4l/SvREWjyk=; b=HWRHeBA3Oq87zKwCth8mb5wk8hkjt1 dBkZCSg+f7Ik5ziMbjESmzoB4txYiUzGTTqRwfB6g4afumJXRRxdx4bVjc79ZFtk iZN7uqB8iFdIphWUIUG5fvE4wde0sYy7HrPdlqp/TL1vZW1Vrg3DDIp0OR5iPVNg tQUQMPtjIGqeJgAxroPysxJe7OONr0fy9f9Wqu43f0uX+EwXXnRzceLy1NXFjST1 5aGVMVqdlyaVFYF6XN2juI74XwtKlT8zy1CM8g8quilapsuXOxFRuN9o1/awhhLW KUK+IYm7zUsbOGsEMyYQBU2swDN3dCi2HS0JXVHLRHd0sm7bcMjjfVYg== Received: (qmail 3533990 invoked from network); 22 May 2025 08:43:52 +0200 Received: by mail.zeus03.de with UTF8SMTPSA (TLS_AES_256_GCM_SHA384 encrypted, authenticated); 22 May 2025 08:43:52 +0200 X-UD-Smtp-Session: l3s3148p1@OfIDzrM1yM4gAwDPXwj7ADHm2wGe7qss From: Wolfram Sang To: linux-i2c@vger.kernel.org Cc: Alan Stern , Nikita Zhandarovich , Wolfram Sang , Till Harbaum , Andi Shyti Subject: [PATCH] i2c: tiny-usb: disable zero-length read messages Date: Thu, 22 May 2025 08:43:49 +0200 Message-ID: <20250522064349.3823-2-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.47.2 Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This driver passes the length of an i2c_msg directly to usb_control_msg(). If the message is now a read and of length 0, it violates the USB protocol and a warning will be printed. Enable the I2C_AQ_NO_ZERO_LEN_READ quirk for this adapter thus forbidding 0-length read messages altogether. Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-tiny-usb.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/i2c/busses/i2c-tiny-usb.c b/drivers/i2c/busses/i2c-tiny-usb.c index 0f2ed181b266..0cc7c0a816fc 100644 --- a/drivers/i2c/busses/i2c-tiny-usb.c +++ b/drivers/i2c/busses/i2c-tiny-usb.c @@ -138,6 +138,11 @@ static u32 usb_func(struct i2c_adapter *adapter) return ret; } +/* prevent invalid 0-length usb_control_msg */ +static const struct i2c_adapter_quirks usb_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN_READ, +}; + /* This is the actual algorithm we define */ static const struct i2c_algorithm usb_algorithm = { .xfer = usb_xfer, @@ -246,6 +251,7 @@ static int i2c_tiny_usb_probe(struct usb_interface *interface, /* setup i2c adapter description */ dev->adapter.owner = THIS_MODULE; dev->adapter.class = I2C_CLASS_HWMON; + dev->adapter.quirks = &usb_quirks; dev->adapter.algo = &usb_algorithm; dev->adapter.algo_data = dev; snprintf(dev->adapter.name, sizeof(dev->adapter.name),