Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Johan Hovold <johan@kernel.org>
To:     Wolfram Sang <wsa@kernel.org>
Cc:     linux-i2c@vger.kernel.org, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, Johan Hovold <johan@kernel.org>,
        syzbot+9d7dadd15b8819d73f41@syzkaller.appspotmail.com,
        stable@vger.kernel.org, Andrew Lunn <andrew@lunn.ch>
Subject: [PATCH] i2c: robotfuzz-osif: fix control-request directions
Date:   Mon, 24 May 2021 11:09:12 +0200
Message-Id: <20210524090912.3989-1-johan@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

The direction of the pipe argument must match the request-type direction
bit or control requests may fail depending on the host-controller-driver
implementation.

Control transfers without a data stage are treated as OUT requests by
the USB stack and should be using usb_sndctrlpipe(). Failing to do so
will now trigger a warning.

Fix the OSIFI2C_SET_BIT_RATE and OSIFI2C_STOP requests which erroneously
used the osif_usb_read() helper and set the IN direction bit.

Reported-by: syzbot+9d7dadd15b8819d73f41@syzkaller.appspotmail.com
Fixes: 83e53a8f120f ("i2c: Add bus driver for for OSIF USB i2c device.")
Cc: stable@vger.kernel.org      # 3.14
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/i2c/busses/i2c-robotfuzz-osif.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-robotfuzz-osif.c b/drivers/i2c/busses/i2c-robotfuzz-osif.c
index a39f7d092797..66dfa211e736 100644
--- a/drivers/i2c/busses/i2c-robotfuzz-osif.c
+++ b/drivers/i2c/busses/i2c-robotfuzz-osif.c
@@ -83,7 +83,7 @@ static int osif_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
 			}
 		}
 
-		ret = osif_usb_read(adapter, OSIFI2C_STOP, 0, 0, NULL, 0);
+		ret = osif_usb_write(adapter, OSIFI2C_STOP, 0, 0, NULL, 0);
 		if (ret) {
 			dev_err(&adapter->dev, "failure sending STOP\n");
 			return -EREMOTEIO;
@@ -153,7 +153,7 @@ static int osif_probe(struct usb_interface *interface,
 	 * Set bus frequency. The frequency is:
 	 * 120,000,000 / ( 16 + 2 * div * 4^prescale).
 	 * Using dev = 52, prescale = 0 give 100KHz */
-	ret = osif_usb_read(&priv->adapter, OSIFI2C_SET_BIT_RATE, 52, 0,
+	ret = osif_usb_write(&priv->adapter, OSIFI2C_SET_BIT_RATE, 52, 0,
 			    NULL, 0);
 	if (ret) {
 		dev_err(&interface->dev, "failure sending bit rate");
-- 
2.26.3