Fix modules broken by @wchen-r7 's 4275a65 commit.

These modules call check() in the exploit() function and expected to get a CheckCode::Vulnerable, now that check() returns Appears instead of Vulnerable they always refuse to run.
I've flipped the logic, based on examples in other modules, now they refuse to run only if check() positively returns Safe.

Author: cnotin

modules/exploits/windows/local/bthpan.rb

@@ -145,7 +145,7 @@ def exploit
       fail_with(Failure::None, 'Session is already elevated')
     end
 
-    unless check == Exploit::CheckCode::Vulnerable
+    if check == Exploit::CheckCode::Safe
       fail_with(Failure::NotVulnerable, "Exploit not available on this system")
     end
 

modules/exploits/windows/local/mqac_write.rb

@@ -115,7 +115,9 @@ def exploit
 
     # Running on Windows XP versions that aren't listed in the supported list
     # results in a BSOD and so we should not let that happen.
-    return unless check == Exploit::CheckCode::Appears
+    if check == Exploit::CheckCode::Safe
+      fail_with(Failure::NotVulnerable, "Exploit not available on this system")
+    end
 
     base_addr = 0xffff
     handle = open_device('\\\\.\\MQAC', 'FILE_SHARE_WRITE|FILE_SHARE_READ', 0, 'OPEN_EXISTING')

modules/exploits/windows/local/ms13_053_schlamperei.rb

@@ -64,7 +64,7 @@ def initialize(info={})
   def check
     os = sysinfo["OS"]
     unless (os =~ /windows/i)
-      return Exploit::CheckCode::Unknown
+      return Exploit::CheckCode::Safe
     end
 
     file_path = expand_path("%windir%") << "\\system32\\win32k.sys"
@@ -81,7 +81,7 @@ def check
         return Exploit::CheckCode::Appears if revision < 22348
       end
     end
-    return Exploit::CheckCode::Unknown
+    return Exploit::CheckCode::Safe
   end
 
 
@@ -96,7 +96,7 @@ def exploit
       fail_with(Failure::NoTarget, "Running against 64-bit systems is not supported")
     end
 
-    unless check == Exploit::CheckCode::Vulnerable
+    if check == Exploit::CheckCode::Safe
       fail_with(Failure::NotVulnerable, "Exploit not available on this system")
     end
 

modules/exploits/windows/local/ms14_070_tcpip_ioctl.rb

@@ -99,7 +99,7 @@ def exploit
       fail_with(Failure::NoTarget, "Running against 64-bit systems is not supported")
     end
 
-    unless check == Exploit::CheckCode::Vulnerable
+    if check == Exploit::CheckCode::Safe
       fail_with(Failure::NotVulnerable, "Exploit not available on this system")
     end
 

modules/exploits/windows/local/virtual_box_guest_additions.rb

@@ -138,7 +138,7 @@ def exploit
       fail_with(Failure::NoTarget, "Running against 64-bit systems is not supported")
     end
 
-    unless check == Exploit::CheckCode::Vulnerable
+    if check == Exploit::CheckCode::Safe
       fail_with(Failure::NotVulnerable, "Exploit not available on this system")
     end