On Sun, Jan 12, 2025 at 09:55:58AM +0000, Qasim Ijaz wrote:
> This patch addresses a null-ptr-deref in qt2_process_read_urb() due to
> an incorrect bounds check in the following:
Thanks for the fix. This looks correct, but your patch is whitespace
damaged (tabs replaced with spaces) and does not apply.
Can you please fix your mail setup and resend a v3? (Make sure to send
it to yourself first.)
When doing so, please use the common patch prefix for this driver:
USB: serial: quatech2:
> ""
You can drop these (markup?) quotes.
> if (newport > serial->num_ports) {
> dev_err(&port->dev,
> "%s - port change to invalid port: %i\n",
> __func__, newport);
> break;
> }
> ""
>
> The condition doesn't account for the valid range of the serial->port
> buffer, which is from 0 to serial->num_ports - 1. When newport is equal
> to serial->num_ports, the assignment of "port" in the
> following code is out-of-bounds and NULL:
>
> ""
> serial_priv->current_port = newport;
> port = serial->port[serial_priv->current_port];
>
> ""
>
> The fix checks if newport is greater than or equal to serial->num_ports
> indicating it is out-of-bounds.
>
> Reported-by: syzbot <syzbot+506479ebf12fe435d01a@xxxxxxxxxxxxxxxxxxxxxxxxx>
> Closes: https://syzkaller.appspot.com/bug?extid=506479ebf12fe435d01a
> Signed-off-by: Qasim Ijaz <qasdev00@xxxxxxxxx>
And please include a Fixes and CC stable tag:
Fixes: f7a33e608d9a ("USB: serial: add quatech2 usb to serial driver")
Cc: stable@xxxxxxxxxxxxxxx # 3.5
Johan
