[patch v2] ncpfs: don't allow negative timeouts

[Dan Carpenter <dan.carpenter@oracle.com>]

This code causes a static checker warning because it's a user controlled
variable where we cap the upper bound but not the lower bound.  Let's
return an -EINVAL for negative timeouts.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v2: in the original I just ignored the invalid data and went with the
    default but now it returns -EINVAL.

diff --git a/fs/ncpfs/ioctl.c b/fs/ncpfs/ioctl.c
index 79b1130..ebf45d2 100644
--- a/fs/ncpfs/ioctl.c
+++ b/fs/ncpfs/ioctl.c
@@ -525,7 +525,9 @@ static long __ncp_ioctl(struct inode *inode, unsigned int cmd, unsigned long arg
 			switch (rqdata.cmd) {
 				case NCP_LOCK_EX:
 				case NCP_LOCK_SH:
-						if (rqdata.timeout == 0)
+						if (rqdata.timeout < 0)
+							return -EINVAL;
+						else if (rqdata.timeout == 0)
 							rqdata.timeout = NCP_LOCK_DEFAULT_TIMEOUT;
 						else if (rqdata.timeout > NCP_LOCK_MAX_TIMEOUT)
 							rqdata.timeout = NCP_LOCK_MAX_TIMEOUT;