3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Johan Hovold <johan@xxxxxxxxxx>
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 <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/serial/io_ti.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/usb/serial/io_ti.c
+++ b/drivers/usb/serial/io_ti.c
@@ -2210,8 +2210,11 @@ static void change_port_settings(struct
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);