[PATCH][serial-next] serial-uartlite: fix null pointer dereference on pointer port

From: Colin King
Date: Tue Nov 13 2018 - 04:38:19 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Pointer port is dereferenced on port->private_data when assigning pointer
pdata before port is null checked, leading to a potential null pointer
dereference. Fix this by assigning pdata after the null pointer check on
port.

Detected by CoverityScan, CID#1475434 ("Dereference before null check")

Fixes: 3b209d253e7f ("serial-uartlite: Do not use static struct uart_driver out of probe()")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/tty/serial/uartlite.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c
index 4a7989df5ff5..0eff33cd9f24 100644
--- a/drivers/tty/serial/uartlite.c
+++ b/drivers/tty/serial/uartlite.c
@@ -715,10 +715,12 @@ static int ulite_release(struct device *dev)
static int __maybe_unused ulite_suspend(struct device *dev)
{
struct uart_port *port = dev_get_drvdata(dev);
- struct uartlite_data *pdata = port->private_data;

- if (port)
+ if (port) {
+ struct uartlite_data *pdata = port->private_data;
+
uart_suspend_port(pdata->ulite_uart_driver, port);
+ }

return 0;
}
--
2.19.1