Changeset 278425 in webkit for trunk/Source/JavaScriptCore/jit/ExecutableAllocationFuzz.cpp

Timestamp:

Jun 3, 2021, 3:44:03 PM (4 years ago)

Author:

[email protected]

Message:

Unreviewed, reverting r278356.
​https://bugs.webkit.org/show_bug.cgi?id=226606

"Breaks jsc tests".

Reverted changeset:

"Convert small JIT pool tests into executable fuzzing"
​https://bugs.webkit.org/show_bug.cgi?id=226279
​https://trac.webkit.org/changeset/278356

File:

• trunk/Source/JavaScriptCore/jit/ExecutableAllocationFuzz.cpp (modified) (4 diffs)

trunk/Source/JavaScriptCore/jit/ExecutableAllocationFuzz.cpp

@@ -30 +30 @@
 #include <wtf/Atomics.h>
 #include <wtf/DataLog.h>
-#include <wtf/WeakRandom.h>
 
 namespace JSC {
@@ -42 +41 @@
 ExecutableAllocationFuzzResult doExecutableAllocationFuzzing()
 {
-    static WeakRandom random(Options::seedOfVMRandomForFuzzer() ? Options::seedOfVMRandomForFuzzer() : cryptographicallyRandomNumber());
-
     ASSERT(Options::useExecutableAllocationFuzz());
     
-    unsigned numChecks = s_numberOfExecutableAllocationFuzzChecks.value++;
-
-    if (numChecks == Options::fireExecutableAllocationFuzzAt()) {
+    unsigned oldValue;
+    unsigned newValue;
+    do {
+        oldValue = s_numberOfExecutableAllocationFuzzChecks.load();
+        newValue = oldValue + 1;
+    } while (!s_numberOfExecutableAllocationFuzzChecks.compareExchangeWeak(oldValue, newValue));
+    
+    if (newValue == Options::fireExecutableAllocationFuzzAt()) {
         if (Options::verboseExecutableAllocationFuzz()) {
             dataLog("Will pretend to fail executable allocation.\n");
@@ -55 +57 @@
         return PretendToFailExecutableAllocation;
     }
-
+    
     if (Options::fireExecutableAllocationFuzzAtOrAfter()
-        && numChecks >= Options::fireExecutableAllocationFuzzAtOrAfter()) {
+        && newValue >= Options::fireExecutableAllocationFuzzAtOrAfter()) {
         if (Options::verboseExecutableAllocationFuzz()) {
             dataLog("Will pretend to fail executable allocation.\n");
@@ -63 +65 @@
         }
         return PretendToFailExecutableAllocation;
-    } else if (!Options::fireExecutableAllocationFuzzAt() && random.getUint32() < UINT_MAX * Options::randomIntegrityAuditRate())
-        return PretendToFailExecutableAllocation;
+    }
     
     return AllowNormalExecutableAllocation;