From 1e6e9c4c36f9626d5ad2b63aa7ad5686dde737e7 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Thu, 11 May 2017 11:41:21 +0200 Subject: [PATCH] USB: serial: io_ti: fix div-by-zero in set_termios commit 6aeb75e6adfaed16e58780309613a578fe1ee90b upstream. Fix a division-by-zero in set_termios when debugging is enabled and a high-enough speed has been requested so that the divisor value becomes zero. Instead of just fixing the offending debug statement, cap the baud rate at the base as a zero divisor value also appears to crash the firmware. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/io_ti.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c index f1a8fdcd8674..e98532feb0cc 100644 --- a/drivers/usb/serial/io_ti.c +++ b/drivers/usb/serial/io_ti.c @@ -2349,8 +2349,11 @@ static void change_port_settings(struct tty_struct *tty, if (!baud) { /* pick a default, any default... */ baud = 9600; - } else + } else { + /* Avoid a zero divisor. */ + baud = min(baud, 461550); tty_encode_baud_rate(tty, baud, baud); + } edge_port->baud_rate = baud; config->wBaudRate = (__u16)((461550L + baud/2) / baud); -- 2.34.1