Fix vulnerability in LockSettings service

Fixes bug 30003944

Change-Id: I8700d4424c6186c8d5e71d2fdede0223ad86904d
(cherry picked from commit 2d71384)

Author: Jim Miller

core/java/com/android/internal/widget/LockPatternUtils.java

@@ -291,7 +291,7 @@ public boolean checkPattern(List<LockPatternView.Cell> pattern, int userId)
                 return false;
             }
         } catch (RemoteException re) {
-            return true;
+            return false;
         }
     }
 
@@ -340,7 +340,7 @@ public boolean checkPassword(String password, int userId) throws RequestThrottle
                 return false;
             }
         } catch (RemoteException re) {
-            return true;
+            return false;
         }
     }
 

services/core/java/com/android/server/LockSettingsService.java

@@ -519,6 +519,9 @@ public VerifyCredentialResponse verifyPattern(String pattern, long challenge, in
     private VerifyCredentialResponse doVerifyPattern(String pattern, boolean hasChallenge,
             long challenge, int userId) throws RemoteException {
        checkPasswordReadPermission(userId);
+       if (TextUtils.isEmpty(pattern)) {
+           throw new IllegalArgumentException("Pattern can't be null or empty");
+       }
        CredentialHash storedHash = mStorage.readPatternHash(userId);
        boolean shouldReEnrollBaseZero = storedHash != null && storedHash.isBaseZeroPattern;
 
@@ -575,6 +578,9 @@ public VerifyCredentialResponse verifyPassword(String password, long challenge,
     private VerifyCredentialResponse doVerifyPassword(String password, boolean hasChallenge,
             long challenge, int userId) throws RemoteException {
        checkPasswordReadPermission(userId);
+       if (TextUtils.isEmpty(password)) {
+           throw new IllegalArgumentException("Password can't be null or empty");
+       }
        CredentialHash storedHash = mStorage.readPasswordHash(userId);
        return verifyCredential(userId, storedHash, password, hasChallenge, challenge,
                new CredentialUtil() {