[PATCH 3.18 02/29] USB: serial: keyspan_pda: fix modem-status error handling
From: Greg Kroah-Hartman
Date: Fri Jul 20 2018 - 08:25:49 EST
3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Johan Hovold <johan@xxxxxxxxxx>
commit 01b3cdfca263a17554f7b249d20a247b2a751521 upstream.
Fix broken modem-status error handling which could lead to bits of slab
data leaking to user space.
Fixes: 3b36a8fd6777 ("usb: fix uninitialized variable warning in keyspan_pda")
Cc: stable <stable@xxxxxxxxxxxxxxx> # 2.6.27
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/serial/keyspan_pda.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/usb/serial/keyspan_pda.c
+++ b/drivers/usb/serial/keyspan_pda.c
@@ -373,8 +373,10 @@ static int keyspan_pda_get_modem_info(st
3, /* get pins */
USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_IN,
0, 0, data, 1, 2000);
- if (rc >= 0)
+ if (rc == 1)
*value = *data;
+ else if (rc >= 0)
+ rc = -EIO;
kfree(data);
return rc;