| From | Willy Tarreau <> | Subject | [PATCH 3.10 163/250] USB: serial: safe_serial: fix information leak in completion handler | Date | Thu, 8 Jun 2017 00:59:09 +0200 |
| |
From: Johan Hovold <johan@kernel.org>
commit 8c76d7cd520ebffc1ea9ea0850d87a224a50c7f2 upstream.
Add missing sanity check to the bulk-in completion handler to avoid an integer underflow that could be triggered by a malicious device.
This avoids leaking up to 56 bytes from after the URB transfer buffer to user space.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Willy Tarreau <w@1wt.eu> --- drivers/usb/serial/safe_serial.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/usb/serial/safe_serial.c b/drivers/usb/serial/safe_serial.c index 21cd7bf..8e24f8f 100644 --- a/drivers/usb/serial/safe_serial.c +++ b/drivers/usb/serial/safe_serial.c @@ -215,6 +215,11 @@ static void safe_process_read_urb(struct urb *urb) if (!safe) goto out; + if (length < 2) { + dev_err(&port->dev, "malformed packet\n"); + return; + } + fcs = fcs_compute10(data, length, CRC10_INITFCS); if (fcs) { dev_err(&port->dev, "%s - bad CRC %x\n", __func__, fcs); -- 2.8.0.rc2.1.gbe9624a
|