freezer: handle exception in locks file format

Safeguard /proc/locks processing from wrongly formatted /proc/locks
files

Bug: 179171387
Test: could not reproduce the issue, but verified that no crashes
occurred in a prolonged test (4hrs+)

Change-Id: Ia8a12903f2e520e51780c8b05876aa1c9083e92b
(cherry picked from commit fb4f4073f6)

core/java/android/os/Process.java

@@ -1406,7 +1406,7 @@ public class Process {
      *
      * @hide
      */
-    public static boolean hasFileLocks(int pid) throws IOException {
+    public static boolean hasFileLocks(int pid) throws Exception {
         BufferedReader br = null;
 
         try {
@@ -1418,8 +1418,13 @@ public class Process {
 
                 for (int i = 0; i < 5 && st.hasMoreTokens(); i++) {
                     String str = st.nextToken();
-                    if (i == 4 && Integer.parseInt(str) == pid) {
+                    try {
-                        return true;
+                        if (i == 4 && Integer.parseInt(str) == pid) {
+                            return true;
+                        }
+                    } catch (NumberFormatException nfe) {
+                        throw new Exception("Exception parsing /proc/locks at \" "
+                                + line +  " \", token #" + i);
                     }
                 }
             }

services/core/java/com/android/server/am/CachedAppOptimizer.java

@@ -1114,7 +1114,7 @@ public final class CachedAppOptimizer {
                     }
                     return;
                 }
-            } catch (IOException e) {
+            } catch (Exception e) {
                 Slog.e(TAG_AM, "Not freezing. Unable to check file locks for " + name + "(" + pid
                         + "): " + e);
                 return;
@@ -1192,7 +1192,7 @@ public final class CachedAppOptimizer {
                         unfreezeAppLocked(proc);
                     }
                 }
-            } catch (IOException e) {
+            } catch (Exception e) {
                 Slog.e(TAG_AM, "Unable to check file locks for " + name + "(" + pid + "): " + e);
                 synchronized (mAm) {
                     unfreezeAppLocked(proc);