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 9B44C651B3; Tue, 23 Jan 2024 00:59:30 +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=1705971570; cv=none; b=InUKi0gW9xcpfHogAXSFrPp3+HnTM9S30vDVWXBjQmVoNJutyHgvUcUqP51ZHMAP4JOazcYKG4JynRybmCBthfo6aAHENhQXNvBSSFy2enNk/P50je3Ix29xuDg/v6eFkxrFiwGJZcfYKQMg96hGKnkOOmfmawRYH8pedIkbr5c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705971570; c=relaxed/simple; bh=xCJbNeqg/40B0MN/xR4oyY3EYnZd7nsKGFdmVO4PGCI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=nVzXP3zhOEQlZDkxGMIV8O7A31GJ1eRu6ATOsLY3DpHAu5xbccEy/fV+F85XHqFHx1DSdbmDiVwmYSknpySGZIH0TQMPcjbYm90YkfnATSShUUe8qQKgW2AIC+jdrA9trWcccK+ApP53jJDCHBNdonWuXglYbzANFf5T+A9d9Q0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MuqSYHNT; 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="MuqSYHNT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4AC67C433C7; Tue, 23 Jan 2024 00:59:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1705971570; bh=xCJbNeqg/40B0MN/xR4oyY3EYnZd7nsKGFdmVO4PGCI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MuqSYHNTBL8WyYuIDNVYs0KQVyUCTiBHzMxFnB7/BeW+zauCnuf5+d13LvscgDYHz jNUbQEPLfVPVERNHoFmB0X1zI5NUvCIFmbagzOgRR3m6D9tKw/zrkP3cSjTjh9B8uU nIHct5QwkNyszN+EMhU34heDdBQEfIFhI4QW1YRE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Lino Sanfilippo Subject: [PATCH 6.1 270/417] serial: core: fix sanitizing check for RTS settings Date: Mon, 22 Jan 2024 15:57:18 -0800 Message-ID: <20240122235801.205865967@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240122235751.480367507@linuxfoundation.org> References: <20240122235751.480367507@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lino Sanfilippo commit 4afeced55baa391490b61ed9164867e2927353ed upstream. Among other things uart_sanitize_serial_rs485() tests the sanity of the RTS settings in a RS485 configuration that has been passed by userspace. If RTS-on-send and RTS-after-send are both set or unset the configuration is adjusted and RTS-after-send is disabled and RTS-on-send enabled. This however makes only sense if both RTS modes are actually supported by the driver. With commit be2e2cb1d281 ("serial: Sanitize rs485_struct") the code does take the driver support into account but only checks if one of both RTS modes are supported. This may lead to the errorneous result of RTS-on-send being set even if only RTS-after-send is supported. Fix this by changing the implemented logic: First clear all unsupported flags in the RS485 configuration, then adjust an invalid RTS setting by taking into account which RTS mode is supported. Cc: Fixes: be2e2cb1d281 ("serial: Sanitize rs485_struct") Reviewed-by: Ilpo Järvinen Signed-off-by: Lino Sanfilippo Link: https://lore.kernel.org/r/20240103061818.564-4-l.sanfilippo@kunbus.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/serial_core.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -1353,19 +1353,27 @@ static void uart_sanitize_serial_rs485(s return; } + rs485->flags &= supported_flags; + /* Pick sane settings if the user hasn't */ - if ((supported_flags & (SER_RS485_RTS_ON_SEND|SER_RS485_RTS_AFTER_SEND)) && - !(rs485->flags & SER_RS485_RTS_ON_SEND) == + if (!(rs485->flags & SER_RS485_RTS_ON_SEND) == !(rs485->flags & SER_RS485_RTS_AFTER_SEND)) { - dev_warn_ratelimited(port->dev, - "%s (%d): invalid RTS setting, using RTS_ON_SEND instead\n", - port->name, port->line); - rs485->flags |= SER_RS485_RTS_ON_SEND; - rs485->flags &= ~SER_RS485_RTS_AFTER_SEND; - supported_flags |= SER_RS485_RTS_ON_SEND|SER_RS485_RTS_AFTER_SEND; - } + if (supported_flags & SER_RS485_RTS_ON_SEND) { + rs485->flags |= SER_RS485_RTS_ON_SEND; + rs485->flags &= ~SER_RS485_RTS_AFTER_SEND; - rs485->flags &= supported_flags; + dev_warn_ratelimited(port->dev, + "%s (%d): invalid RTS setting, using RTS_ON_SEND instead\n", + port->name, port->line); + } else { + rs485->flags |= SER_RS485_RTS_AFTER_SEND; + rs485->flags &= ~SER_RS485_RTS_ON_SEND; + + dev_warn_ratelimited(port->dev, + "%s (%d): invalid RTS setting, using RTS_AFTER_SEND instead\n", + port->name, port->line); + } + } uart_sanitize_serial_rs485_delays(port, rs485);