[PATCH 5.4 03/27] serial: sprd: Fix a dereference warning
From: Greg Kroah-Hartman
Date: Wed Apr 01 2020 - 12:22:22 EST
From: Lanqing Liu <liuhhome@xxxxxxxxx>
commit efc176929a3505a30c3993ddd393b40893649bd2 upstream.
We should validate if the 'sup' is NULL or not before freeing DMA
memory, to fix below warning.
"drivers/tty/serial/sprd_serial.c:1141 sprd_remove()
error: we previously assumed 'sup' could be null (see line 1132)"
Fixes: f4487db58eb7 ("serial: sprd: Add DMA mode support")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Lanqing Liu <liuhhome@xxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/e2bd92691538e95b04a2c2a728f3292e1617018f.1584325957.git.liuhhome@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/sprd_serial.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/drivers/tty/serial/sprd_serial.c
+++ b/drivers/tty/serial/sprd_serial.c
@@ -1103,14 +1103,13 @@ static int sprd_remove(struct platform_d
if (sup) {
uart_remove_one_port(&sprd_uart_driver, &sup->port);
sprd_port[sup->port.line] = NULL;
+ sprd_rx_free_buf(sup);
sprd_ports_num--;
}
if (!sprd_ports_num)
uart_unregister_driver(&sprd_uart_driver);
- sprd_rx_free_buf(sup);
-
return 0;
}