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i2c: robotfuzz-osif: fix control-request directions
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commit 4ca070e upstream.

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: 83e53a8 ("i2c: Add bus driver for for OSIF USB i2c device.")
Cc: stable@vger.kernel.org      # 3.14
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Johan Hovold authored and Sasha Levin committed Jun 30, 2021
1 parent 9436cdf commit f376dd8
Showing 1 changed file with 2 additions and 2 deletions.
4 changes: 2 additions & 2 deletions drivers/i2c/busses/i2c-robotfuzz-osif.c
Original file line number Diff line number Diff line change
Expand Up @@ -86,7 +86,7 @@ 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;
Expand Down Expand Up @@ -156,7 +156,7 @@ 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");
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