From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (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 EBABC6D12 for ; Wed, 7 Apr 2021 10:23:50 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 4C24F613A7; Wed, 7 Apr 2021 10:23:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617791030; bh=JoyaSKfz5lR15SASchNoM6NPJ9rBSNCEnNwcns+Ic8M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hVm4yc7/Jc+fMzxiXFr4yVMSck59nHkDa5WjTh4XQg1saY4N+c248Szi7QkVyLTx7 NIZtyBlrV1HSL0n2fbhpfFlJXItBjBSPVu62ciurxp+YCglXeU5+O0IPfqmVRtg/AE dBz7An31bhEw0u4zfQ/w8PavaF/VIKcQbU/vxRp8MovY/D0nXb8A95xgQIGjl7Wxz6 iv5UkIEQphdpGK0fAh2HLZwotfKOKVULL8Gvv5AR9IqzBbnho9/YmEe5f+6AWVkOvR tKUb5uMbKl81odQIQN5XiUaF1pcYlbWSLFHq0ehd6rJd6QJ4EuJnnvcBBnzN+s4TI+ z5Ze/23MHjeiw== Received: from johan by xi.lan with local (Exim 4.93.0.4) (envelope-from ) id 1lU5La-0008R4-PD; Wed, 07 Apr 2021 12:23:42 +0200 From: Johan Hovold To: Greg Kroah-Hartman Cc: Jiri Slaby , linux-staging@lists.linux.dev, greybus-dev@lists.linaro.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org Subject: [PATCH 02/16] staging: fwserial: fix TIOCSSERIAL permission check Date: Wed, 7 Apr 2021 12:23:20 +0200 Message-Id: <20210407102334.32361-3-johan@kernel.org> X-Mailer: git-send-email 2.26.3 In-Reply-To: <20210407102334.32361-1-johan@kernel.org> References: <20210407102334.32361-1-johan@kernel.org> X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Changing the port close-delay parameter is a privileged operation so make sure to return -EPERM if a regular user tries to change it. Fixes: 7355ba3445f2 ("staging: fwserial: Add TTY-over-Firewire serial driver") Cc: stable@vger.kernel.org # 3.8 Signed-off-by: Johan Hovold --- drivers/staging/fwserial/fwserial.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/staging/fwserial/fwserial.c b/drivers/staging/fwserial/fwserial.c index c963848522b1..440d11423812 100644 --- a/drivers/staging/fwserial/fwserial.c +++ b/drivers/staging/fwserial/fwserial.c @@ -1232,20 +1232,24 @@ static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss) { struct fwtty_port *port = tty->driver_data; + unsigned int cdelay; if (ss->irq != 0 || ss->port != 0 || ss->custom_divisor != 0 || ss->baud_base != 400000000) return -EPERM; + cdelay = msecs_to_jiffies(ss->close_delay * 10); + mutex_lock(&port->port.mutex); if (!capable(CAP_SYS_ADMIN)) { - if (((ss->flags & ~ASYNC_USR_MASK) != + if (cdelay != port->port.close_delay || + ((ss->flags & ~ASYNC_USR_MASK) != (port->port.flags & ~ASYNC_USR_MASK))) { mutex_unlock(&port->port.mutex); return -EPERM; } } - port->port.close_delay = msecs_to_jiffies(ss->close_delay * 10); + port->port.close_delay = cdelay; mutex_unlock(&port->port.mutex); return 0; -- 2.26.3