lkml.org 
[lkml]   [2017]   [Sep]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH 3.16 023/233] USB: serial: io_ti: fix div-by-zero in set_termios
3.16.48-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Johan Hovold <johan@kernel.org>

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@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
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
@@ -2215,8 +2215,11 @@ 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);
\
 
 \ /
  Last update: 2017-09-10 01:18    [W:0.900 / U:6.828 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site