lkml.org 
[lkml]   [2019]   [Dec]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] media: dvb: check return value digitv_ctrl_msg
Date
For fixing syzbot "KMSAN: uninit-value in digitv_rc_query"

In scenario testing for syzbot, failure reading from
digitv_ctrl_msg() [1].

Eg:
[ 91.846657][ T3844] dvb-usb: bulk message failed: -22 (7/0)

digitv_rc_query() always return 0. But in this case a wrong thing happens.

Reported-by: syzbot+6bf9606ee955b646c0e1@syzkaller.appspotmail.com
Tested-by: syzbot+6bf9606ee955b646c0e1@syzkaller.appspotmail.com

[1]: https://syzkaller.appspot.com/text?tag=CrashLog&x=16860a63600000
[2]: https://groups.google.com/d/msg/syzkaller-bugs/-TXIJAZ0J9Q/T4PEUQoeAQAJ

Signed-off-by: Phong Tran <tranmanphong@gmail.com>
---
drivers/media/usb/dvb-usb/digitv.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/media/usb/dvb-usb/digitv.c b/drivers/media/usb/dvb-usb/digitv.c
index dd5bb230cec1..61bc8945e6b9 100644
--- a/drivers/media/usb/dvb-usb/digitv.c
+++ b/drivers/media/usb/dvb-usb/digitv.c
@@ -231,17 +231,21 @@ static struct rc_map_table rc_map_digitv_table[] = {
static int digitv_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
{
int i;
- u8 key[5];
+ u8 key[5] = { 0 };
u8 b[4] = { 0 };
+ int ret;

*event = 0;
*state = REMOTE_NO_KEY_PRESSED;

- digitv_ctrl_msg(d,USB_READ_REMOTE,0,NULL,0,&key[1],4);
-
+ ret = digitv_ctrl_msg(d, USB_READ_REMOTE, 0, NULL, 0, &key[1], 4);
+ if (ret < 0)
+ return ret;
/* Tell the device we've read the remote. Not sure how necessary
this is, but the Nebula SDK does it. */
- digitv_ctrl_msg(d,USB_WRITE_REMOTE,0,b,4,NULL,0);
+ ret = digitv_ctrl_msg(d, USB_WRITE_REMOTE, 0, b, 4, NULL, 0);
+ if (ret < 0)
+ return ret;

/* if something is inside the buffer, simulate key press */
if (key[1] != 0)
--
2.20.1
\
 
 \ /
  Last update: 2019-12-03 01:42    [W:0.030 / U:0.908 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site