lkml.org 
[lkml]   [2019]   [Mar]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] tty: fix NULL pointer issue when tty_port ops is not set
Date
Unlike 'client_ops' which is initialized to 'default_client_ops', the
port operations 'ops' may be left to NULL.
Check the 'ops' value before checking the 'ops->x' value.

Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
---
drivers/tty/tty_port.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 044c3cb..a9e12b3 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -325,7 +325,7 @@ static void tty_port_shutdown(struct tty_port *port, struct tty_struct *tty)
if (tty && C_HUPCL(tty))
tty_port_lower_dtr_rts(port);

- if (port->ops->shutdown)
+ if (port->ops && port->ops->shutdown)
port->ops->shutdown(port);
}
out:
@@ -398,7 +398,7 @@ EXPORT_SYMBOL_GPL(tty_port_tty_wakeup);
*/
int tty_port_carrier_raised(struct tty_port *port)
{
- if (port->ops->carrier_raised == NULL)
+ if (!port->ops || !port->ops->carrier_raised)
return 1;
return port->ops->carrier_raised(port);
}
@@ -414,7 +414,7 @@ EXPORT_SYMBOL(tty_port_carrier_raised);
*/
void tty_port_raise_dtr_rts(struct tty_port *port)
{
- if (port->ops->dtr_rts)
+ if (port->ops && port->ops->dtr_rts)
port->ops->dtr_rts(port, 1);
}
EXPORT_SYMBOL(tty_port_raise_dtr_rts);
@@ -429,7 +429,7 @@ EXPORT_SYMBOL(tty_port_raise_dtr_rts);
*/
void tty_port_lower_dtr_rts(struct tty_port *port)
{
- if (port->ops->dtr_rts)
+ if (port->ops && port->ops->dtr_rts)
port->ops->dtr_rts(port, 0);
}
EXPORT_SYMBOL(tty_port_lower_dtr_rts);
@@ -684,7 +684,7 @@ int tty_port_open(struct tty_port *port, struct tty_struct *tty,

if (!tty_port_initialized(port)) {
clear_bit(TTY_IO_ERROR, &tty->flags);
- if (port->ops->activate) {
+ if (port->ops && port->ops->activate) {
int retval = port->ops->activate(port, tty);
if (retval) {
mutex_unlock(&port->mutex);
--
2.7.4
\
 
 \ /
  Last update: 2019-03-21 16:44    [W:0.050 / U:0.896 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site