From: Qiujun Huang <hqjagain@xxxxxxxxx> commit 57aa9f294b09463492f604feaa5cc719beaace32 upstream. Fix slab-out-of-bounds read in the interrupt-URB completion handler. The boundary condition should be (length - 1) as we access data[position + 1]. Reported-and-tested-by: syzbot+37ba33391ad5f3935bbd@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Qiujun Huang <hqjagain@xxxxxxxxx> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/serial/io_edgeport.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/serial/io_edgeport.c +++ b/drivers/usb/serial/io_edgeport.c @@ -634,7 +634,7 @@ static void edge_interrupt_callback(stru /* grab the txcredits for the ports if available */ position = 2; portNumber = 0; - while ((position < length) && + while ((position < length - 1) && (portNumber < edge_serial->serial->num_ports)) { txCredits = data[position] | (data[position+1] << 8); if (txCredits) {