aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/generic/patches-3.3/993-mpcore_wdt_fix_wdioc_setoptions_handling.patch
blob: fa261ce6482fbb07dc5c7043ba76655957c1d219 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
According to the include/linux/watchdog.h WDIOC_SETOPTIONS is
classified as 'read from device' ioctl call:
  #define WDIOC_SETOPTIONS        _IOR(WATCHDOG_IOCTL_BASE, 4, int)

However, the driver 'mpcore_wdt' performs 'copy_from_user' only if
_IOC_WRITE is set, thus the local variable 'uarg' which is used in
WDIOC_SETOPTIONS handling remains uninitialized.

The proper way to fix this is to bind WDIOC_SETOPTIONS to _IOW,
but this will break compatibility.
So adding additional condition for performing 'copy_from_user'.

Signed-off-by: Vitaly Kuzmichev <vkuzmichev@mvista.com>
---
 drivers/watchdog/mpcore_wdt.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

--- a/drivers/watchdog/mpcore_wdt.c
+++ b/drivers/watchdog/mpcore_wdt.c
@@ -233,7 +233,8 @@ static long mpcore_wdt_ioctl(struct file
 	if (_IOC_DIR(cmd) && _IOC_SIZE(cmd) > sizeof(uarg))
 		return -ENOTTY;
 
-	if (_IOC_DIR(cmd) & _IOC_WRITE) {
+	if ((_IOC_DIR(cmd) & _IOC_WRITE)
+			|| cmd == WDIOC_SETOPTIONS) {
 		ret = copy_from_user(&uarg, (void __user *)arg, _IOC_SIZE(cmd));
 		if (ret)
 			return -EFAULT;