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")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
---
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 93c6c9b08daa..8a069aa154ed 100644
--- a/drivers/usb/serial/safe_serial.c
+++ b/drivers/usb/serial/safe_serial.c
@@ -200,6 +200,11 @@ 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);
--
2.12.0
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
