Changeset 219273 in webkit

Timestamp:

Jul 7, 2017 5:03:27 PM (7 years ago)

Author:

commit-queue@webkit.org

Message:

Lower the max_protection for the separated heap
​https://bugs.webkit.org/show_bug.cgi?id=174281

Patch by AJ Ringer <​aringer@apple.com> on 2017-07-07
Reviewed by Oliver Hunt.

Switch to vm_protect so we can set maximum page protection.

• jit/ExecutableAllocator.cpp:

(JSC::FixedVMPoolExecutableAllocator::initializeSeparatedWXHeaps):
(JSC::ExecutableAllocator::allocate):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• jit/ExecutableAllocator.cpp (modified) (4 diffs)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2017-07-07  AJ Ringer  <aringer@apple.com>
+
+        Lower the max_protection for the separated heap
+        https://bugs.webkit.org/show_bug.cgi?id=174281
+
+        Reviewed by Oliver Hunt.
+
+        Switch to vm_protect so we can set maximum page protection.
+
+        * jit/ExecutableAllocator.cpp:
+        (JSC::FixedVMPoolExecutableAllocator::initializeSeparatedWXHeaps):
+        (JSC::ExecutableAllocator::allocate):
+
 2017-07-07  Devin Rousso  <drousso@apple.com>
 

trunk/Source/JavaScriptCore/jit/ExecutableAllocator.cpp

@@ -213 +213 @@
 #if USE(EXECUTE_ONLY_JIT_WRITE_FUNCTION)
         // Prevent reading the write thunk code.
-        result = mprotect(stubBase, stubSize, VM_PROT_EXECUTE_ONLY);
+        result = vm_protect(mach_task_self(), reinterpret_cast<vm_address_t>(stubBase), stubSize, true, VM_PROT_EXECUTE);
         RELEASE_ASSERT(!result);
 #endif
 
         // Prevent writing into the executable JIT mapping.
-        result = mprotect(jitBase, jitSize, VM_PROT_READ | VM_PROT_EXECUTE);
+        result = vm_protect(mach_task_self(), reinterpret_cast<vm_address_t>(jitBase), jitSize, true, VM_PROT_READ | VM_PROT_EXECUTE);
         RELEASE_ASSERT(!result);
 
         // Prevent execution in the writable JIT mapping.
-        result = mprotect((void*)writableAddr, jitSize, VM_PROT_READ | VM_PROT_WRITE);
+        result = vm_protect(mach_task_self(), static_cast<vm_address_t>(writableAddr), jitSize, true, VM_PROT_READ | VM_PROT_WRITE);
         RELEASE_ASSERT(!result);
 
@@ -397 +397 @@
         dataLog("Allocating ", sizeInBytes, " bytes of executable memory with ", stats.bytesAllocated, " bytes allocated, ", stats.bytesReserved, " bytes reserved, and ", stats.bytesCommitted, " committed.\n");
     }
-    
+
     if (effort != JITCompilationCanFail && Options::reportMustSucceedExecutableAllocations()) {
         dataLog("Allocating ", sizeInBytes, " bytes of executable memory with JITCompilationMustSucceed.\n");
         WTFReportBacktrace();
     }
-    
+
     if (effort == JITCompilationCanFail
         && doExecutableAllocationFuzzingIfEnabled() == PretendToFailExecutableAllocation)
         return nullptr;
-    
+
     if (effort == JITCompilationCanFail) {
         // Don't allow allocations if we are down to reserve.
@@ -419 +419 @@
         }
     }
-    
+
     RefPtr<ExecutableMemoryHandle> result = allocator->allocate(sizeInBytes, ownerUID);
     if (!result) {
@@ -452 +452 @@
 }
 #endif
-    
+
 }