lkml.org 
[lkml]   [2022]   [Jul]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.14 41/43] serial: 8250: fix return error code in serial8250_request_std_resource()
Date
From: Yi Yang <yiyang13@huawei.com>

commit 6e690d54cfa802f939cefbd2fa2c91bd0b8bd1b6 upstream.

If port->mapbase = NULL in serial8250_request_std_resource() , it need
return a error code instead of 0. If uart_set_info() fail to request new
regions by serial8250_request_std_resource() but the return value of
serial8250_request_std_resource() is 0, The system incorrectly considers
that the resource application is successful and does not attempt to
restore the old setting. A null pointer reference is triggered when the
port resource is later invoked.

Signed-off-by: Yi Yang <yiyang13@huawei.com>
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/r/20220628083515.64138-1-yiyang13@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/serial/8250/8250_port.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2884,8 +2884,10 @@ static int serial8250_request_std_resour
case UPIO_MEM32BE:
case UPIO_MEM16:
case UPIO_MEM:
- if (!port->mapbase)
+ if (!port->mapbase) {
+ ret = -EINVAL;
break;
+ }

if (!request_mem_region(port->mapbase, size, "serial")) {
ret = -EBUSY;

\
 
 \ /
  Last update: 2022-07-19 14:03    [W:0.199 / U:0.132 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site