Changeset 236839 in webkit

Timestamp:

Oct 4, 2018 12:23:34 PM (6 years ago)

Author:

mark.lam@apple.com

Message:

Disable Options::useWebAssemblyFastMemory() on linux if ASAN signal handling is not disabled.
​https://bugs.webkit.org/show_bug.cgi?id=190283
<rdar://problem/45015752>

Reviewed by Keith Miller.

• runtime/Options.cpp:

(JSC::Options::initialize):

• wasm/WasmFaultSignalHandler.cpp:

(JSC::Wasm::enableFastMemory):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• runtime/Options.cpp (modified) (1 diff)
• wasm/WasmFaultSignalHandler.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2018-10-04  Mark Lam  <mark.lam@apple.com>
+
+        Disable Options::useWebAssemblyFastMemory() on linux if ASAN signal handling is not disabled.
+        https://bugs.webkit.org/show_bug.cgi?id=190283
+        <rdar://problem/45015752>
+
+        Reviewed by Keith Miller.
+
+        * runtime/Options.cpp:
+        (JSC::Options::initialize):
+        * wasm/WasmFaultSignalHandler.cpp:
+        (JSC::Wasm::enableFastMemory):
+
 2018-10-03  Ross Kirsling  <ross.kirsling@sony.com>
 

trunk/Source/JavaScriptCore/runtime/Options.cpp

@@ -573 +573 @@
             if (Options::useMachForExceptions())
                 handleSignalsWithMach();
+#endif
+
+#if ASAN_ENABLED && OS(LINUX) && ENABLE(WEBASSEMBLY_FAST_MEMORY)
+            if (Options::useWebAssemblyFastMemory()) {
+                const char* asanOptions = getenv("ASAN_OPTIONS");
+                bool okToUseWebAssemblyFastMemory = asanOptions
+                    && (strstr(asanOptions, "allow_user_segv_handler=1") || strstr(asanOptions, "handle_segv=0"));
+                if (!okToUseWebAssemblyFastMemory) {
+                    dataLogLn("WARNING: ASAN interferes with JSC signal handlers; useWebAssemblyFastMemory will be disabled.");
+                    Options::useWebAssemblyFastMemory() = false;
+                }
+            }
 #endif
         });

trunk/Source/JavaScriptCore/wasm/WasmFaultSignalHandler.cpp

@@ -124 +124 @@
 void enableFastMemory()
 {
+#if ENABLE(WEBASSEMBLY_FAST_MEMORY)
     static std::once_flag once;
     std::call_once(once, [] {
@@ -129 +130 @@
             return;
 
-#if ENABLE(WEBASSEMBLY_FAST_MEMORY)
         installSignalHandler(Signal::BadAccess, [] (Signal signal, SigInfo& sigInfo, PlatformRegisters& ucontext) {
             return trapHandler(signal, sigInfo, ucontext);
@@ -136 +136 @@
         codeLocations.construct();
         fastHandlerInstalled = true;
+    });
 #endif // ENABLE(WEBASSEMBLY_FAST_MEMORY)
-    });
 }