ffi: keep FFI functions non-constructible#65184

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Merged
nodejs-github-bot merged 1 commit into from
Aug 17, 2026
+75 −45
Merged

ffi: keep FFI functions non-constructible #65184

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70 changes: 36 additions & 34 deletions lib/internal/ffi-shared-buffer.js
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Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -198,6 +198,8 @@ function inheritMetadata(wrapper, rawFn, nargs) {
// arguments out of it into invocation-local storage before `ffi_call` and
// reads the return value back only after, so nested/reentrant calls into
// the same function are safe.
// Concise methods do not have [[Construct]], unlike function expressions, so
// use them below to match the native FFI functions' non-constructible behavior.
function wrapWithSharedBuffer(rawFn, signature) {
if (rawFn == null) return rawFn;
const buffer = rawFn[kSbSharedBuffer];
Expand DownExpand Up@@ -254,7 +256,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
// so arity specialization wouldn't buy much here.
assert(slowInvoke !== undefined,
'FFI: shared-buffer raw function with pointer arguments is missing kSbInvokeSlow');
wrapper = function(...args) {
wrapper = { invoke(...args) {
if (args.length !== nargs) {
throwFFIArgCountError(nargs, args.length);
}
Expand All@@ -271,7 +273,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
}
rawFn();
return retGetter === null ? undefined : retGetter(view, 0, true);
};
} }.invoke;
} else {
// Arity specialization avoids the per-call `Array` allocation of
// `...args`; the void/non-void split removes a per-call branch on
Expand All@@ -295,67 +297,67 @@ function buildNumericWrapper(
/* c8 ignore start */
if (nargs === 0) {
if (retGetter === null) {
return function() {
return { invoke() {
if (arguments.length !== 0) {
throwFFIArgCountError(0, arguments.length);
}
rawFn();
};
} }.invoke;
}
return function() {
return { invoke() {
if (arguments.length !== 0) {
throwFFIArgCountError(0, arguments.length);
}
rawFn();
return retGetter(view, 0, true);
};
} }.invoke;
}
/* c8 ignore stop */
if (nargs === 1) {
const i0 = argInfos[0];
const o0 = argOffsets[0];
if (retGetter === null) {
return function(a0) {
return { invoke(a0) {
if (arguments.length !== 1) {
throwFFIArgCountError(1, arguments.length);
}
writeNumericArg(view, i0, o0, a0, 0);
rawFn();
};
} }.invoke;
}
return function(a0) {
return { invoke(a0) {
if (arguments.length !== 1) {
throwFFIArgCountError(1, arguments.length);
}
writeNumericArg(view, i0, o0, a0, 0);
rawFn();
return retGetter(view, 0, true);
};
} }.invoke;
}
if (nargs === 2) {
const i0 = argInfos[0];
const i1 = argInfos[1];
const o0 = argOffsets[0];
const o1 = argOffsets[1];
if (retGetter === null) {
return function(a0, a1) {
return { invoke(a0, a1) {
if (arguments.length !== 2) {
throwFFIArgCountError(2, arguments.length);
}
writeNumericArg(view, i0, o0, a0, 0);
writeNumericArg(view, i1, o1, a1, 1);
rawFn();
};
} }.invoke;
}
return function(a0, a1) {
return { invoke(a0, a1) {
if (arguments.length !== 2) {
throwFFIArgCountError(2, arguments.length);
}
writeNumericArg(view, i0, o0, a0, 0);
writeNumericArg(view, i1, o1, a1, 1);
rawFn();
return retGetter(view, 0, true);
};
} }.invoke;
}
if (nargs === 3) {
const i0 = argInfos[0];
Expand All@@ -365,17 +367,17 @@ function buildNumericWrapper(
const o1 = argOffsets[1];
const o2 = argOffsets[2];
if (retGetter === null) {
return function(a0, a1, a2) {
return { invoke(a0, a1, a2) {
if (arguments.length !== 3) {
throwFFIArgCountError(3, arguments.length);
}
writeNumericArg(view, i0, o0, a0, 0);
writeNumericArg(view, i1, o1, a1, 1);
writeNumericArg(view, i2, o2, a2, 2);
rawFn();
};
} }.invoke;
}
return function(a0, a1, a2) {
return { invoke(a0, a1, a2) {
if (arguments.length !== 3) {
throwFFIArgCountError(3, arguments.length);
}
Expand All@@ -384,7 +386,7 @@ function buildNumericWrapper(
writeNumericArg(view, i2, o2, a2, 2);
rawFn();
return retGetter(view, 0, true);
};
} }.invoke;
}
if (nargs === 4) {
const i0 = argInfos[0];
Expand All@@ -396,7 +398,7 @@ function buildNumericWrapper(
const o2 = argOffsets[2];
const o3 = argOffsets[3];
if (retGetter === null) {
return function(a0, a1, a2, a3) {
return { invoke(a0, a1, a2, a3) {
if (arguments.length !== 4) {
throwFFIArgCountError(4, arguments.length);
}
Expand All@@ -405,9 +407,9 @@ function buildNumericWrapper(
writeNumericArg(view, i2, o2, a2, 2);
writeNumericArg(view, i3, o3, a3, 3);
rawFn();
};
} }.invoke;
}
return function(a0, a1, a2, a3) {
return { invoke(a0, a1, a2, a3) {
if (arguments.length !== 4) {
throwFFIArgCountError(4, arguments.length);
}
Expand All@@ -417,7 +419,7 @@ function buildNumericWrapper(
writeNumericArg(view, i3, o3, a3, 3);
rawFn();
return retGetter(view, 0, true);
};
} }.invoke;
}
if (nargs === 5) {
const i0 = argInfos[0];
Expand All@@ -431,7 +433,7 @@ function buildNumericWrapper(
const o3 = argOffsets[3];
const o4 = argOffsets[4];
if (retGetter === null) {
return function(a0, a1, a2, a3, a4) {
return { invoke(a0, a1, a2, a3, a4) {
if (arguments.length !== 5) {
throwFFIArgCountError(5, arguments.length);
}
Expand All@@ -441,9 +443,9 @@ function buildNumericWrapper(
writeNumericArg(view, i3, o3, a3, 3);
writeNumericArg(view, i4, o4, a4, 4);
rawFn();
};
} }.invoke;
}
return function(a0, a1, a2, a3, a4) {
return { invoke(a0, a1, a2, a3, a4) {
if (arguments.length !== 5) {
throwFFIArgCountError(5, arguments.length);
}
Expand All@@ -454,7 +456,7 @@ function buildNumericWrapper(
writeNumericArg(view, i4, o4, a4, 4);
rawFn();
return retGetter(view, 0, true);
};
} }.invoke;
}
if (nargs === 6) {
const i0 = argInfos[0];
Expand All@@ -470,7 +472,7 @@ function buildNumericWrapper(
const o4 = argOffsets[4];
const o5 = argOffsets[5];
if (retGetter === null) {
return function(a0, a1, a2, a3, a4, a5) {
return { invoke(a0, a1, a2, a3, a4, a5) {
if (arguments.length !== 6) {
throwFFIArgCountError(6, arguments.length);
}
Expand All@@ -481,9 +483,9 @@ function buildNumericWrapper(
writeNumericArg(view, i4, o4, a4, 4);
writeNumericArg(view, i5, o5, a5, 5);
rawFn();
};
} }.invoke;
}
return function(a0, a1, a2, a3, a4, a5) {
return { invoke(a0, a1, a2, a3, a4, a5) {
if (arguments.length !== 6) {
throwFFIArgCountError(6, arguments.length);
}
Expand All@@ -495,22 +497,22 @@ function buildNumericWrapper(
writeNumericArg(view, i5, o5, a5, 5);
rawFn();
return retGetter(view, 0, true);
};
} }.invoke;
}
// 7+ args: further specialization is diminishing returns and bloats
// this builder.
if (retGetter === null) {
return function(...args) {
return { invoke(...args) {
if (args.length !== nargs) {
throwFFIArgCountError(nargs, args.length);
}
for (let i = 0; i < nargs; i++) {
writeNumericArg(view, argInfos[i], argOffsets[i], args[i], i);
}
rawFn();
};
} }.invoke;
}
return function(...args) {
return { invoke(...args) {
if (args.length !== nargs) {
throwFFIArgCountError(nargs, args.length);
}
Expand All@@ -519,7 +521,7 @@ function buildNumericWrapper(
}
rawFn();
return retGetter(view, 0, true);
};
} }.invoke;
}

module.exports = {
Expand Down
18 changes: 10 additions & 8 deletions lib/internal/ffi/fast-api.js
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Original file line numberDiff line numberDiff line change
Expand Up@@ -222,6 +222,8 @@ function throwIfFastLibraryClosed(state) {
}
}

// Concise methods do not have [[Construct]], unlike function expressions.
// Keep wrappers non-constructible to match the native FFI functions.
function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
if (rawFn === undefined || rawFn === null) {
return rawFn;
Expand DownExpand Up@@ -255,7 +257,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
const memory0 = needsRawPointerConversion(t0) || string0;
const fastBufferInvoke = needsPointerLikeConversion(t0) ?
rawFn[kFastBufferInvoke] : undefined;
wrapper = function(a0) {
wrapper = { invoke(a0) {
throwIfFastLibraryClosed(state);
if (arguments.length !== 1) {
throwFFIArgCountError(1, arguments.length);
Expand All@@ -279,13 +281,13 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
arg = getRawPointer(arg);
}
return rawFn(arg);
};
} }.invoke;
} else if (nargs === 2) {
const c0 = ArrayPrototypeIncludes(indexes, 0);
const c1 = ArrayPrototypeIncludes(indexes, 1);
const t0 = argumentTypes[0];
const t1 = argumentTypes[1];
wrapper = function(a0, a1) {
wrapper = { invoke(a0, a1) {
throwIfFastLibraryClosed(state);
if (arguments.length !== 2) {
throwFFIArgCountError(2, arguments.length);
Expand All@@ -299,15 +301,15 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
} finally {
if (stringCall) exitStringConversion(stringState);
}
};
} }.invoke;
} else if (nargs === 3) {
const c0 = ArrayPrototypeIncludes(indexes, 0);
const c1 = ArrayPrototypeIncludes(indexes, 1);
const c2 = ArrayPrototypeIncludes(indexes, 2);
const t0 = argumentTypes[0];
const t1 = argumentTypes[1];
const t2 = argumentTypes[2];
wrapper = function(a0, a1, a2) {
wrapper = { invoke(a0, a1, a2) {
throwIfFastLibraryClosed(state);
if (arguments.length !== 3) {
throwFFIArgCountError(3, arguments.length);
Expand All@@ -323,9 +325,9 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
} finally {
if (stringCall) exitStringConversion(stringState);
}
};
} }.invoke;
} else {
wrapper = function(...args) {
wrapper = { invoke(...args) {
throwIfFastLibraryClosed(state);
if (args.length !== nargs) {
throwFFIArgCountError(nargs, args.length);
Expand All@@ -349,7 +351,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
} finally {
if (stringCall) exitStringConversion(stringState);
}
};
} }.invoke;
}

return inheritMetadata(wrapper, rawFn, nargs);
Expand Down
11 changes: 8 additions & 3 deletions src/node_ffi.cc
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Original file line numberDiff line numberDiff line change
Expand Up@@ -324,7 +324,9 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
maybe_ret = Function::New(context,
use_sb ? DynamicLibrary::InvokeFunctionSB
: DynamicLibrary::InvokeFunction,
info->object());
info->object(),
0,
v8::ConstructorBehavior::kThrow);
}

Local<Function> ret;
Expand DownExpand Up@@ -377,8 +379,11 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
// (strings, Buffers, ArrayBuffers, and ArrayBufferViews).
if (has_ptr_args) {
Local<Function> slow_fn;
if (!Function::New(
context, DynamicLibrary::InvokeFunction, info->object())
if (!Function::New(context,
DynamicLibrary::InvokeFunction,
info->object(),
0,
v8::ConstructorBehavior::kThrow)
.ToLocal(&slow_fn)) {
return MaybeLocal<Function>();
}
Expand Down
21 changes: 21 additions & 0 deletions test/ffi/test-ffi-dynamic-library.js
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Original file line numberDiff line numberDiff line change
Expand Up@@ -67,6 +67,27 @@ test('dlopen resolves functions from definitions', () => {
}
});

test('FFI functions are not constructible', () => {
const { lib, functions } = ffi.dlopen(libraryPath, {
add_i32: fixtureSymbols.add_i32,
multiply_f64: fixtureSymbols.multiply_f64,
});

try {
assert.strictEqual(Object.hasOwn(functions.add_i32, 'prototype'), false);
assert.strictEqual(
Object.hasOwn(functions.multiply_f64, 'prototype'), false);
assert.throws(
() => Reflect.construct(functions.add_i32, [20, 22]),
TypeError);
assert.throws(
() => Reflect.construct(functions.multiply_f64, [6, 7]),
TypeError);
} finally {
lib.close();
}
});

test('DynamicLibrary exposes functions and symbols', () => {
const lib = new ffi.DynamicLibrary(libraryPath);

Expand Down
Loading
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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ffi: keep FFI functions non-constructible#65184

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 Merged

nodejs-github-bot
merged 1 commit into

from

Aug 17, 2026

+75

−45

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ffi: keep FFI functions non-constructible
#65184
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70 changes: 36 additions & 34 deletions
lib/internal/ffi-shared-buffer.js

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Original file line numberDiff line numberDiff line change
Expand Up@@ -198,6 +198,8 @@ function inheritMetadata(wrapper, rawFn, nargs) {
// arguments out of it into invocation-local storage before `ffi_call` and
// reads the return value back only after, so nested/reentrant calls into
// the same function are safe.
// Concise methods do not have [[Construct]], unlike function expressions, so
// use them below to match the native FFI functions' non-constructible behavior.
function wrapWithSharedBuffer(rawFn, signature) {
 if (rawFn == null) return rawFn;
 const buffer = rawFn[kSbSharedBuffer];
Expand DownExpand Up@@ -254,7 +256,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 // so arity specialization wouldn't buy much here.
 assert(slowInvoke !== undefined,
 'FFI: shared-buffer raw function with pointer arguments is missing kSbInvokeSlow');
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -271,7 +273,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 }
 rawFn();
 return retGetter === null ? undefined : retGetter(view, 0, true);
 };
 } }.invoke;
 } else {
 // Arity specialization avoids the per-call `Array` allocation of
 // `...args`; the void/non-void split removes a per-call branch on
Expand All@@ -295,67 +297,67 @@ function buildNumericWrapper(
 /* c8 ignore start */
 if (nargs === 0) {
 if (retGetter === null) {
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 /* c8 ignore stop */
 if (nargs === 1) {
 const i0 = argInfos[0];
 const o0 = argOffsets[0];
 if (retGetter === null) {
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 2) {
 const i0 = argInfos[0];
 const i1 = argInfos[1];
 const o0 = argOffsets[0];
 const o1 = argOffsets[1];
 if (retGetter === null) {
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 3) {
 const i0 = argInfos[0];
Expand All@@ -365,17 +367,17 @@ function buildNumericWrapper(
 const o1 = argOffsets[1];
 const o2 = argOffsets[2];
 if (retGetter === null) {
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
Expand All@@ -384,7 +386,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 4) {
 const i0 = argInfos[0];
Expand All@@ -396,7 +398,7 @@ function buildNumericWrapper(
 const o2 = argOffsets[2];
 const o3 = argOffsets[3];
 if (retGetter === null) {
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -405,9 +407,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -417,7 +419,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 5) {
 const i0 = argInfos[0];
Expand All@@ -431,7 +433,7 @@ function buildNumericWrapper(
 const o3 = argOffsets[3];
 const o4 = argOffsets[4];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -441,9 +443,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -454,7 +456,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 6) {
 const i0 = argInfos[0];
Expand All@@ -470,7 +472,7 @@ function buildNumericWrapper(
 const o4 = argOffsets[4];
 const o5 = argOffsets[5];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -481,9 +483,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -495,22 +497,22 @@ function buildNumericWrapper(
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 // 7+ args: further specialization is diminishing returns and bloats
 // this builder.
 if (retGetter === null) {
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
 for (let i = 0; i < nargs; i++) {
 writeNumericArg(view, argInfos[i], argOffsets[i], args[i], i);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -519,7 +521,7 @@ function buildNumericWrapper(
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
}

module.exports = {
Expand Down

18 changes: 10 additions & 8 deletions
lib/internal/ffi/fast-api.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -222,6 +222,8 @@ function throwIfFastLibraryClosed(state) {
 }
}

// Concise methods do not have [[Construct]], unlike function expressions.
// Keep wrappers non-constructible to match the native FFI functions.
function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 if (rawFn === undefined || rawFn === null) {
 return rawFn;
Expand DownExpand Up@@ -255,7 +257,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 const memory0 = needsRawPointerConversion(t0) || string0;
 const fastBufferInvoke = needsPointerLikeConversion(t0) ?
 rawFn[kFastBufferInvoke] : undefined;
 wrapper = function(a0) {
 wrapper = { invoke(a0) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
Expand All@@ -279,13 +281,13 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 arg = getRawPointer(arg);
 }
 return rawFn(arg);
 };
 } }.invoke;
 } else if (nargs === 2) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 wrapper = function(a0, a1) {
 wrapper = { invoke(a0, a1) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
Expand All@@ -299,15 +301,15 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else if (nargs === 3) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const c2 = ArrayPrototypeIncludes(indexes, 2);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 const t2 = argumentTypes[2];
 wrapper = function(a0, a1, a2) {
 wrapper = { invoke(a0, a1, a2) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
Expand All@@ -323,9 +325,9 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else {
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 throwIfFastLibraryClosed(state);
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
Expand All@@ -349,7 +351,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 }

 return inheritMetadata(wrapper, rawFn, nargs);
Expand Down

11 changes: 8 additions & 3 deletions
src/node_ffi.cc

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -324,7 +324,9 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 maybe_ret = Function::New(context,
 use_sb ? DynamicLibrary::InvokeFunctionSB
 : DynamicLibrary::InvokeFunction,
 info->object());
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow);
 }

 Local<Function> ret;
Expand DownExpand Up@@ -377,8 +379,11 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 // (strings, Buffers, ArrayBuffers, and ArrayBufferViews).
 if (has_ptr_args) {
 Local<Function> slow_fn;
 if (!Function::New(
 context, DynamicLibrary::InvokeFunction, info->object())
 if (!Function::New(context,
 DynamicLibrary::InvokeFunction,
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow)
 .ToLocal(&slow_fn)) {
 return MaybeLocal<Function>();
 }
Expand Down

21 changes: 21 additions & 0 deletions
test/ffi/test-ffi-dynamic-library.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -67,6 +67,27 @@ test('dlopen resolves functions from definitions', () => {
 }
});

test('FFI functions are not constructible', () => {
 const { lib, functions } = ffi.dlopen(libraryPath, {
 add_i32: fixtureSymbols.add_i32,
 multiply_f64: fixtureSymbols.multiply_f64,
 });

 try {
 assert.strictEqual(Object.hasOwn(functions.add_i32, 'prototype'), false);
 assert.strictEqual(
 Object.hasOwn(functions.multiply_f64, 'prototype'), false);
 assert.throws(
 () => Reflect.construct(functions.add_i32, [20, 22]),
 TypeError);
 assert.throws(
 () => Reflect.construct(functions.multiply_f64, [6, 7]),
 TypeError);
 } finally {
 lib.close();
 }
});

test('DynamicLibrary exposes functions and symbols', () => {
 const lib = new ffi.DynamicLibrary(libraryPath);

Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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ffi: keep FFI functions non-constructible#65184

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 Merged

nodejs-github-bot
merged 1 commit into

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Aug 17, 2026

+75

−45

 Merged


ffi: keep FFI functions non-constructible
#65184
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70 changes: 36 additions & 34 deletions
lib/internal/ffi-shared-buffer.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -198,6 +198,8 @@ function inheritMetadata(wrapper, rawFn, nargs) {
// arguments out of it into invocation-local storage before `ffi_call` and
// reads the return value back only after, so nested/reentrant calls into
// the same function are safe.
// Concise methods do not have [[Construct]], unlike function expressions, so
// use them below to match the native FFI functions' non-constructible behavior.
function wrapWithSharedBuffer(rawFn, signature) {
 if (rawFn == null) return rawFn;
 const buffer = rawFn[kSbSharedBuffer];
Expand DownExpand Up@@ -254,7 +256,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 // so arity specialization wouldn't buy much here.
 assert(slowInvoke !== undefined,
 'FFI: shared-buffer raw function with pointer arguments is missing kSbInvokeSlow');
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -271,7 +273,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 }
 rawFn();
 return retGetter === null ? undefined : retGetter(view, 0, true);
 };
 } }.invoke;
 } else {
 // Arity specialization avoids the per-call `Array` allocation of
 // `...args`; the void/non-void split removes a per-call branch on
Expand All@@ -295,67 +297,67 @@ function buildNumericWrapper(
 /* c8 ignore start */
 if (nargs === 0) {
 if (retGetter === null) {
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 /* c8 ignore stop */
 if (nargs === 1) {
 const i0 = argInfos[0];
 const o0 = argOffsets[0];
 if (retGetter === null) {
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 2) {
 const i0 = argInfos[0];
 const i1 = argInfos[1];
 const o0 = argOffsets[0];
 const o1 = argOffsets[1];
 if (retGetter === null) {
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 3) {
 const i0 = argInfos[0];
Expand All@@ -365,17 +367,17 @@ function buildNumericWrapper(
 const o1 = argOffsets[1];
 const o2 = argOffsets[2];
 if (retGetter === null) {
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
Expand All@@ -384,7 +386,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 4) {
 const i0 = argInfos[0];
Expand All@@ -396,7 +398,7 @@ function buildNumericWrapper(
 const o2 = argOffsets[2];
 const o3 = argOffsets[3];
 if (retGetter === null) {
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -405,9 +407,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -417,7 +419,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 5) {
 const i0 = argInfos[0];
Expand All@@ -431,7 +433,7 @@ function buildNumericWrapper(
 const o3 = argOffsets[3];
 const o4 = argOffsets[4];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -441,9 +443,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -454,7 +456,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 6) {
 const i0 = argInfos[0];
Expand All@@ -470,7 +472,7 @@ function buildNumericWrapper(
 const o4 = argOffsets[4];
 const o5 = argOffsets[5];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -481,9 +483,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -495,22 +497,22 @@ function buildNumericWrapper(
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 // 7+ args: further specialization is diminishing returns and bloats
 // this builder.
 if (retGetter === null) {
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
 for (let i = 0; i < nargs; i++) {
 writeNumericArg(view, argInfos[i], argOffsets[i], args[i], i);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -519,7 +521,7 @@ function buildNumericWrapper(
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
}

module.exports = {
Expand Down

18 changes: 10 additions & 8 deletions
lib/internal/ffi/fast-api.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -222,6 +222,8 @@ function throwIfFastLibraryClosed(state) {
 }
}

// Concise methods do not have [[Construct]], unlike function expressions.
// Keep wrappers non-constructible to match the native FFI functions.
function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 if (rawFn === undefined || rawFn === null) {
 return rawFn;
Expand DownExpand Up@@ -255,7 +257,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 const memory0 = needsRawPointerConversion(t0) || string0;
 const fastBufferInvoke = needsPointerLikeConversion(t0) ?
 rawFn[kFastBufferInvoke] : undefined;
 wrapper = function(a0) {
 wrapper = { invoke(a0) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
Expand All@@ -279,13 +281,13 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 arg = getRawPointer(arg);
 }
 return rawFn(arg);
 };
 } }.invoke;
 } else if (nargs === 2) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 wrapper = function(a0, a1) {
 wrapper = { invoke(a0, a1) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
Expand All@@ -299,15 +301,15 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else if (nargs === 3) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const c2 = ArrayPrototypeIncludes(indexes, 2);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 const t2 = argumentTypes[2];
 wrapper = function(a0, a1, a2) {
 wrapper = { invoke(a0, a1, a2) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
Expand All@@ -323,9 +325,9 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else {
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 throwIfFastLibraryClosed(state);
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
Expand All@@ -349,7 +351,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 }

 return inheritMetadata(wrapper, rawFn, nargs);
Expand Down

11 changes: 8 additions & 3 deletions
src/node_ffi.cc

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -324,7 +324,9 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 maybe_ret = Function::New(context,
 use_sb ? DynamicLibrary::InvokeFunctionSB
 : DynamicLibrary::InvokeFunction,
 info->object());
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow);
 }

 Local<Function> ret;
Expand DownExpand Up@@ -377,8 +379,11 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 // (strings, Buffers, ArrayBuffers, and ArrayBufferViews).
 if (has_ptr_args) {
 Local<Function> slow_fn;
 if (!Function::New(
 context, DynamicLibrary::InvokeFunction, info->object())
 if (!Function::New(context,
 DynamicLibrary::InvokeFunction,
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow)
 .ToLocal(&slow_fn)) {
 return MaybeLocal<Function>();
 }
Expand Down

21 changes: 21 additions & 0 deletions
test/ffi/test-ffi-dynamic-library.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -67,6 +67,27 @@ test('dlopen resolves functions from definitions', () => {
 }
});

test('FFI functions are not constructible', () => {
 const { lib, functions } = ffi.dlopen(libraryPath, {
 add_i32: fixtureSymbols.add_i32,
 multiply_f64: fixtureSymbols.multiply_f64,
 });

 try {
 assert.strictEqual(Object.hasOwn(functions.add_i32, 'prototype'), false);
 assert.strictEqual(
 Object.hasOwn(functions.multiply_f64, 'prototype'), false);
 assert.throws(
 () => Reflect.construct(functions.add_i32, [20, 22]),
 TypeError);
 assert.throws(
 () => Reflect.construct(functions.multiply_f64, [6, 7]),
 TypeError);
 } finally {
 lib.close();
 }
});

test('DynamicLibrary exposes functions and symbols', () => {
 const lib = new ffi.DynamicLibrary(libraryPath);

Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
ffi: keep FFI functions non-constructible#65184

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By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

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to your account

 Merged

nodejs-github-bot
merged 1 commit into

from

Aug 17, 2026

+75

−45

 Merged


ffi: keep FFI functions non-constructible
#65184
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70 changes: 36 additions & 34 deletions
lib/internal/ffi-shared-buffer.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -198,6 +198,8 @@ function inheritMetadata(wrapper, rawFn, nargs) {
// arguments out of it into invocation-local storage before `ffi_call` and
// reads the return value back only after, so nested/reentrant calls into
// the same function are safe.
// Concise methods do not have [[Construct]], unlike function expressions, so
// use them below to match the native FFI functions' non-constructible behavior.
function wrapWithSharedBuffer(rawFn, signature) {
 if (rawFn == null) return rawFn;
 const buffer = rawFn[kSbSharedBuffer];
Expand DownExpand Up@@ -254,7 +256,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 // so arity specialization wouldn't buy much here.
 assert(slowInvoke !== undefined,
 'FFI: shared-buffer raw function with pointer arguments is missing kSbInvokeSlow');
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -271,7 +273,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 }
 rawFn();
 return retGetter === null ? undefined : retGetter(view, 0, true);
 };
 } }.invoke;
 } else {
 // Arity specialization avoids the per-call `Array` allocation of
 // `...args`; the void/non-void split removes a per-call branch on
Expand All@@ -295,67 +297,67 @@ function buildNumericWrapper(
 /* c8 ignore start */
 if (nargs === 0) {
 if (retGetter === null) {
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 /* c8 ignore stop */
 if (nargs === 1) {
 const i0 = argInfos[0];
 const o0 = argOffsets[0];
 if (retGetter === null) {
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 2) {
 const i0 = argInfos[0];
 const i1 = argInfos[1];
 const o0 = argOffsets[0];
 const o1 = argOffsets[1];
 if (retGetter === null) {
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 3) {
 const i0 = argInfos[0];
Expand All@@ -365,17 +367,17 @@ function buildNumericWrapper(
 const o1 = argOffsets[1];
 const o2 = argOffsets[2];
 if (retGetter === null) {
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
Expand All@@ -384,7 +386,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 4) {
 const i0 = argInfos[0];
Expand All@@ -396,7 +398,7 @@ function buildNumericWrapper(
 const o2 = argOffsets[2];
 const o3 = argOffsets[3];
 if (retGetter === null) {
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -405,9 +407,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -417,7 +419,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 5) {
 const i0 = argInfos[0];
Expand All@@ -431,7 +433,7 @@ function buildNumericWrapper(
 const o3 = argOffsets[3];
 const o4 = argOffsets[4];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -441,9 +443,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -454,7 +456,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 6) {
 const i0 = argInfos[0];
Expand All@@ -470,7 +472,7 @@ function buildNumericWrapper(
 const o4 = argOffsets[4];
 const o5 = argOffsets[5];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -481,9 +483,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -495,22 +497,22 @@ function buildNumericWrapper(
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 // 7+ args: further specialization is diminishing returns and bloats
 // this builder.
 if (retGetter === null) {
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
 for (let i = 0; i < nargs; i++) {
 writeNumericArg(view, argInfos[i], argOffsets[i], args[i], i);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -519,7 +521,7 @@ function buildNumericWrapper(
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
}

module.exports = {
Expand Down

18 changes: 10 additions & 8 deletions
lib/internal/ffi/fast-api.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -222,6 +222,8 @@ function throwIfFastLibraryClosed(state) {
 }
}

// Concise methods do not have [[Construct]], unlike function expressions.
// Keep wrappers non-constructible to match the native FFI functions.
function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 if (rawFn === undefined || rawFn === null) {
 return rawFn;
Expand DownExpand Up@@ -255,7 +257,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 const memory0 = needsRawPointerConversion(t0) || string0;
 const fastBufferInvoke = needsPointerLikeConversion(t0) ?
 rawFn[kFastBufferInvoke] : undefined;
 wrapper = function(a0) {
 wrapper = { invoke(a0) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
Expand All@@ -279,13 +281,13 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 arg = getRawPointer(arg);
 }
 return rawFn(arg);
 };
 } }.invoke;
 } else if (nargs === 2) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 wrapper = function(a0, a1) {
 wrapper = { invoke(a0, a1) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
Expand All@@ -299,15 +301,15 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else if (nargs === 3) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const c2 = ArrayPrototypeIncludes(indexes, 2);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 const t2 = argumentTypes[2];
 wrapper = function(a0, a1, a2) {
 wrapper = { invoke(a0, a1, a2) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
Expand All@@ -323,9 +325,9 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else {
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 throwIfFastLibraryClosed(state);
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
Expand All@@ -349,7 +351,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 }

 return inheritMetadata(wrapper, rawFn, nargs);
Expand Down

11 changes: 8 additions & 3 deletions
src/node_ffi.cc

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -324,7 +324,9 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 maybe_ret = Function::New(context,
 use_sb ? DynamicLibrary::InvokeFunctionSB
 : DynamicLibrary::InvokeFunction,
 info->object());
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow);
 }

 Local<Function> ret;
Expand DownExpand Up@@ -377,8 +379,11 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 // (strings, Buffers, ArrayBuffers, and ArrayBufferViews).
 if (has_ptr_args) {
 Local<Function> slow_fn;
 if (!Function::New(
 context, DynamicLibrary::InvokeFunction, info->object())
 if (!Function::New(context,
 DynamicLibrary::InvokeFunction,
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow)
 .ToLocal(&slow_fn)) {
 return MaybeLocal<Function>();
 }
Expand Down

21 changes: 21 additions & 0 deletions
test/ffi/test-ffi-dynamic-library.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -67,6 +67,27 @@ test('dlopen resolves functions from definitions', () => {
 }
});

test('FFI functions are not constructible', () => {
 const { lib, functions } = ffi.dlopen(libraryPath, {
 add_i32: fixtureSymbols.add_i32,
 multiply_f64: fixtureSymbols.multiply_f64,
 });

 try {
 assert.strictEqual(Object.hasOwn(functions.add_i32, 'prototype'), false);
 assert.strictEqual(
 Object.hasOwn(functions.multiply_f64, 'prototype'), false);
 assert.throws(
 () => Reflect.construct(functions.add_i32, [20, 22]),
 TypeError);
 assert.throws(
 () => Reflect.construct(functions.multiply_f64, [6, 7]),
 TypeError);
 } finally {
 lib.close();
 }
});

test('DynamicLibrary exposes functions and symbols', () => {
 const lib = new ffi.DynamicLibrary(libraryPath);

Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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merged 1 commit into

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Aug 17, 2026

+75

−45

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ffi: keep FFI functions non-constructible
#65184
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70 changes: 36 additions & 34 deletions
lib/internal/ffi-shared-buffer.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -198,6 +198,8 @@ function inheritMetadata(wrapper, rawFn, nargs) {
// arguments out of it into invocation-local storage before `ffi_call` and
// reads the return value back only after, so nested/reentrant calls into
// the same function are safe.
// Concise methods do not have [[Construct]], unlike function expressions, so
// use them below to match the native FFI functions' non-constructible behavior.
function wrapWithSharedBuffer(rawFn, signature) {
 if (rawFn == null) return rawFn;
 const buffer = rawFn[kSbSharedBuffer];
Expand DownExpand Up@@ -254,7 +256,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 // so arity specialization wouldn't buy much here.
 assert(slowInvoke !== undefined,
 'FFI: shared-buffer raw function with pointer arguments is missing kSbInvokeSlow');
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -271,7 +273,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 }
 rawFn();
 return retGetter === null ? undefined : retGetter(view, 0, true);
 };
 } }.invoke;
 } else {
 // Arity specialization avoids the per-call `Array` allocation of
 // `...args`; the void/non-void split removes a per-call branch on
Expand All@@ -295,67 +297,67 @@ function buildNumericWrapper(
 /* c8 ignore start */
 if (nargs === 0) {
 if (retGetter === null) {
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 /* c8 ignore stop */
 if (nargs === 1) {
 const i0 = argInfos[0];
 const o0 = argOffsets[0];
 if (retGetter === null) {
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 2) {
 const i0 = argInfos[0];
 const i1 = argInfos[1];
 const o0 = argOffsets[0];
 const o1 = argOffsets[1];
 if (retGetter === null) {
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 3) {
 const i0 = argInfos[0];
Expand All@@ -365,17 +367,17 @@ function buildNumericWrapper(
 const o1 = argOffsets[1];
 const o2 = argOffsets[2];
 if (retGetter === null) {
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
Expand All@@ -384,7 +386,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 4) {
 const i0 = argInfos[0];
Expand All@@ -396,7 +398,7 @@ function buildNumericWrapper(
 const o2 = argOffsets[2];
 const o3 = argOffsets[3];
 if (retGetter === null) {
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -405,9 +407,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -417,7 +419,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 5) {
 const i0 = argInfos[0];
Expand All@@ -431,7 +433,7 @@ function buildNumericWrapper(
 const o3 = argOffsets[3];
 const o4 = argOffsets[4];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -441,9 +443,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -454,7 +456,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 6) {
 const i0 = argInfos[0];
Expand All@@ -470,7 +472,7 @@ function buildNumericWrapper(
 const o4 = argOffsets[4];
 const o5 = argOffsets[5];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -481,9 +483,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -495,22 +497,22 @@ function buildNumericWrapper(
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 // 7+ args: further specialization is diminishing returns and bloats
 // this builder.
 if (retGetter === null) {
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
 for (let i = 0; i < nargs; i++) {
 writeNumericArg(view, argInfos[i], argOffsets[i], args[i], i);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -519,7 +521,7 @@ function buildNumericWrapper(
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
}

module.exports = {
Expand Down

18 changes: 10 additions & 8 deletions
lib/internal/ffi/fast-api.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -222,6 +222,8 @@ function throwIfFastLibraryClosed(state) {
 }
}

// Concise methods do not have [[Construct]], unlike function expressions.
// Keep wrappers non-constructible to match the native FFI functions.
function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 if (rawFn === undefined || rawFn === null) {
 return rawFn;
Expand DownExpand Up@@ -255,7 +257,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 const memory0 = needsRawPointerConversion(t0) || string0;
 const fastBufferInvoke = needsPointerLikeConversion(t0) ?
 rawFn[kFastBufferInvoke] : undefined;
 wrapper = function(a0) {
 wrapper = { invoke(a0) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
Expand All@@ -279,13 +281,13 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 arg = getRawPointer(arg);
 }
 return rawFn(arg);
 };
 } }.invoke;
 } else if (nargs === 2) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 wrapper = function(a0, a1) {
 wrapper = { invoke(a0, a1) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
Expand All@@ -299,15 +301,15 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else if (nargs === 3) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const c2 = ArrayPrototypeIncludes(indexes, 2);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 const t2 = argumentTypes[2];
 wrapper = function(a0, a1, a2) {
 wrapper = { invoke(a0, a1, a2) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
Expand All@@ -323,9 +325,9 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else {
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 throwIfFastLibraryClosed(state);
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
Expand All@@ -349,7 +351,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 }

 return inheritMetadata(wrapper, rawFn, nargs);
Expand Down

11 changes: 8 additions & 3 deletions
src/node_ffi.cc

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -324,7 +324,9 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 maybe_ret = Function::New(context,
 use_sb ? DynamicLibrary::InvokeFunctionSB
 : DynamicLibrary::InvokeFunction,
 info->object());
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow);
 }

 Local<Function> ret;
Expand DownExpand Up@@ -377,8 +379,11 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 // (strings, Buffers, ArrayBuffers, and ArrayBufferViews).
 if (has_ptr_args) {
 Local<Function> slow_fn;
 if (!Function::New(
 context, DynamicLibrary::InvokeFunction, info->object())
 if (!Function::New(context,
 DynamicLibrary::InvokeFunction,
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow)
 .ToLocal(&slow_fn)) {
 return MaybeLocal<Function>();
 }
Expand Down

21 changes: 21 additions & 0 deletions
test/ffi/test-ffi-dynamic-library.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -67,6 +67,27 @@ test('dlopen resolves functions from definitions', () => {
 }
});

test('FFI functions are not constructible', () => {
 const { lib, functions } = ffi.dlopen(libraryPath, {
 add_i32: fixtureSymbols.add_i32,
 multiply_f64: fixtureSymbols.multiply_f64,
 });

 try {
 assert.strictEqual(Object.hasOwn(functions.add_i32, 'prototype'), false);
 assert.strictEqual(
 Object.hasOwn(functions.multiply_f64, 'prototype'), false);
 assert.throws(
 () => Reflect.construct(functions.add_i32, [20, 22]),
 TypeError);
 assert.throws(
 () => Reflect.construct(functions.multiply_f64, [6, 7]),
 TypeError);
 } finally {
 lib.close();
 }
});

test('DynamicLibrary exposes functions and symbols', () => {
 const lib = new ffi.DynamicLibrary(libraryPath);

Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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ffi: keep FFI functions non-constructible#65184

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 Merged

nodejs-github-bot
merged 1 commit into

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Aug 17, 2026

+75

−45

 Merged


ffi: keep FFI functions non-constructible
#65184
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70 changes: 36 additions & 34 deletions
lib/internal/ffi-shared-buffer.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -198,6 +198,8 @@ function inheritMetadata(wrapper, rawFn, nargs) {
// arguments out of it into invocation-local storage before `ffi_call` and
// reads the return value back only after, so nested/reentrant calls into
// the same function are safe.
// Concise methods do not have [[Construct]], unlike function expressions, so
// use them below to match the native FFI functions' non-constructible behavior.
function wrapWithSharedBuffer(rawFn, signature) {
 if (rawFn == null) return rawFn;
 const buffer = rawFn[kSbSharedBuffer];
Expand DownExpand Up@@ -254,7 +256,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 // so arity specialization wouldn't buy much here.
 assert(slowInvoke !== undefined,
 'FFI: shared-buffer raw function with pointer arguments is missing kSbInvokeSlow');
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -271,7 +273,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 }
 rawFn();
 return retGetter === null ? undefined : retGetter(view, 0, true);
 };
 } }.invoke;
 } else {
 // Arity specialization avoids the per-call `Array` allocation of
 // `...args`; the void/non-void split removes a per-call branch on
Expand All@@ -295,67 +297,67 @@ function buildNumericWrapper(
 /* c8 ignore start */
 if (nargs === 0) {
 if (retGetter === null) {
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 /* c8 ignore stop */
 if (nargs === 1) {
 const i0 = argInfos[0];
 const o0 = argOffsets[0];
 if (retGetter === null) {
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 2) {
 const i0 = argInfos[0];
 const i1 = argInfos[1];
 const o0 = argOffsets[0];
 const o1 = argOffsets[1];
 if (retGetter === null) {
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 3) {
 const i0 = argInfos[0];
Expand All@@ -365,17 +367,17 @@ function buildNumericWrapper(
 const o1 = argOffsets[1];
 const o2 = argOffsets[2];
 if (retGetter === null) {
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
Expand All@@ -384,7 +386,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 4) {
 const i0 = argInfos[0];
Expand All@@ -396,7 +398,7 @@ function buildNumericWrapper(
 const o2 = argOffsets[2];
 const o3 = argOffsets[3];
 if (retGetter === null) {
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -405,9 +407,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -417,7 +419,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 5) {
 const i0 = argInfos[0];
Expand All@@ -431,7 +433,7 @@ function buildNumericWrapper(
 const o3 = argOffsets[3];
 const o4 = argOffsets[4];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -441,9 +443,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -454,7 +456,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 6) {
 const i0 = argInfos[0];
Expand All@@ -470,7 +472,7 @@ function buildNumericWrapper(
 const o4 = argOffsets[4];
 const o5 = argOffsets[5];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -481,9 +483,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -495,22 +497,22 @@ function buildNumericWrapper(
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 // 7+ args: further specialization is diminishing returns and bloats
 // this builder.
 if (retGetter === null) {
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
 for (let i = 0; i < nargs; i++) {
 writeNumericArg(view, argInfos[i], argOffsets[i], args[i], i);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -519,7 +521,7 @@ function buildNumericWrapper(
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
}

module.exports = {
Expand Down

18 changes: 10 additions & 8 deletions
lib/internal/ffi/fast-api.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -222,6 +222,8 @@ function throwIfFastLibraryClosed(state) {
 }
}

// Concise methods do not have [[Construct]], unlike function expressions.
// Keep wrappers non-constructible to match the native FFI functions.
function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 if (rawFn === undefined || rawFn === null) {
 return rawFn;
Expand DownExpand Up@@ -255,7 +257,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 const memory0 = needsRawPointerConversion(t0) || string0;
 const fastBufferInvoke = needsPointerLikeConversion(t0) ?
 rawFn[kFastBufferInvoke] : undefined;
 wrapper = function(a0) {
 wrapper = { invoke(a0) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
Expand All@@ -279,13 +281,13 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 arg = getRawPointer(arg);
 }
 return rawFn(arg);
 };
 } }.invoke;
 } else if (nargs === 2) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 wrapper = function(a0, a1) {
 wrapper = { invoke(a0, a1) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
Expand All@@ -299,15 +301,15 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else if (nargs === 3) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const c2 = ArrayPrototypeIncludes(indexes, 2);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 const t2 = argumentTypes[2];
 wrapper = function(a0, a1, a2) {
 wrapper = { invoke(a0, a1, a2) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
Expand All@@ -323,9 +325,9 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else {
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 throwIfFastLibraryClosed(state);
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
Expand All@@ -349,7 +351,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 }

 return inheritMetadata(wrapper, rawFn, nargs);
Expand Down

11 changes: 8 additions & 3 deletions
src/node_ffi.cc

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -324,7 +324,9 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 maybe_ret = Function::New(context,
 use_sb ? DynamicLibrary::InvokeFunctionSB
 : DynamicLibrary::InvokeFunction,
 info->object());
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow);
 }

 Local<Function> ret;
Expand DownExpand Up@@ -377,8 +379,11 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 // (strings, Buffers, ArrayBuffers, and ArrayBufferViews).
 if (has_ptr_args) {
 Local<Function> slow_fn;
 if (!Function::New(
 context, DynamicLibrary::InvokeFunction, info->object())
 if (!Function::New(context,
 DynamicLibrary::InvokeFunction,
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow)
 .ToLocal(&slow_fn)) {
 return MaybeLocal<Function>();
 }
Expand Down

21 changes: 21 additions & 0 deletions
test/ffi/test-ffi-dynamic-library.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -67,6 +67,27 @@ test('dlopen resolves functions from definitions', () => {
 }
});

test('FFI functions are not constructible', () => {
 const { lib, functions } = ffi.dlopen(libraryPath, {
 add_i32: fixtureSymbols.add_i32,
 multiply_f64: fixtureSymbols.multiply_f64,
 });

 try {
 assert.strictEqual(Object.hasOwn(functions.add_i32, 'prototype'), false);
 assert.strictEqual(
 Object.hasOwn(functions.multiply_f64, 'prototype'), false);
 assert.throws(
 () => Reflect.construct(functions.add_i32, [20, 22]),
 TypeError);
 assert.throws(
 () => Reflect.construct(functions.multiply_f64, [6, 7]),
 TypeError);
 } finally {
 lib.close();
 }
});

test('DynamicLibrary exposes functions and symbols', () => {
 const lib = new ffi.DynamicLibrary(libraryPath);

Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
ffi: keep FFI functions non-constructible#65184

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to your account

 Merged

nodejs-github-bot
merged 1 commit into

from

Aug 17, 2026

+75

−45

 Merged


ffi: keep FFI functions non-constructible
#65184
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70 changes: 36 additions & 34 deletions
lib/internal/ffi-shared-buffer.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -198,6 +198,8 @@ function inheritMetadata(wrapper, rawFn, nargs) {
// arguments out of it into invocation-local storage before `ffi_call` and
// reads the return value back only after, so nested/reentrant calls into
// the same function are safe.
// Concise methods do not have [[Construct]], unlike function expressions, so
// use them below to match the native FFI functions' non-constructible behavior.
function wrapWithSharedBuffer(rawFn, signature) {
 if (rawFn == null) return rawFn;
 const buffer = rawFn[kSbSharedBuffer];
Expand DownExpand Up@@ -254,7 +256,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 // so arity specialization wouldn't buy much here.
 assert(slowInvoke !== undefined,
 'FFI: shared-buffer raw function with pointer arguments is missing kSbInvokeSlow');
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -271,7 +273,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 }
 rawFn();
 return retGetter === null ? undefined : retGetter(view, 0, true);
 };
 } }.invoke;
 } else {
 // Arity specialization avoids the per-call `Array` allocation of
 // `...args`; the void/non-void split removes a per-call branch on
Expand All@@ -295,67 +297,67 @@ function buildNumericWrapper(
 /* c8 ignore start */
 if (nargs === 0) {
 if (retGetter === null) {
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 /* c8 ignore stop */
 if (nargs === 1) {
 const i0 = argInfos[0];
 const o0 = argOffsets[0];
 if (retGetter === null) {
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 2) {
 const i0 = argInfos[0];
 const i1 = argInfos[1];
 const o0 = argOffsets[0];
 const o1 = argOffsets[1];
 if (retGetter === null) {
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 3) {
 const i0 = argInfos[0];
Expand All@@ -365,17 +367,17 @@ function buildNumericWrapper(
 const o1 = argOffsets[1];
 const o2 = argOffsets[2];
 if (retGetter === null) {
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
Expand All@@ -384,7 +386,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 4) {
 const i0 = argInfos[0];
Expand All@@ -396,7 +398,7 @@ function buildNumericWrapper(
 const o2 = argOffsets[2];
 const o3 = argOffsets[3];
 if (retGetter === null) {
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -405,9 +407,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -417,7 +419,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 5) {
 const i0 = argInfos[0];
Expand All@@ -431,7 +433,7 @@ function buildNumericWrapper(
 const o3 = argOffsets[3];
 const o4 = argOffsets[4];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -441,9 +443,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -454,7 +456,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 6) {
 const i0 = argInfos[0];
Expand All@@ -470,7 +472,7 @@ function buildNumericWrapper(
 const o4 = argOffsets[4];
 const o5 = argOffsets[5];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -481,9 +483,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -495,22 +497,22 @@ function buildNumericWrapper(
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 // 7+ args: further specialization is diminishing returns and bloats
 // this builder.
 if (retGetter === null) {
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
 for (let i = 0; i < nargs; i++) {
 writeNumericArg(view, argInfos[i], argOffsets[i], args[i], i);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -519,7 +521,7 @@ function buildNumericWrapper(
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
}

module.exports = {
Expand Down

18 changes: 10 additions & 8 deletions
lib/internal/ffi/fast-api.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -222,6 +222,8 @@ function throwIfFastLibraryClosed(state) {
 }
}

// Concise methods do not have [[Construct]], unlike function expressions.
// Keep wrappers non-constructible to match the native FFI functions.
function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 if (rawFn === undefined || rawFn === null) {
 return rawFn;
Expand DownExpand Up@@ -255,7 +257,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 const memory0 = needsRawPointerConversion(t0) || string0;
 const fastBufferInvoke = needsPointerLikeConversion(t0) ?
 rawFn[kFastBufferInvoke] : undefined;
 wrapper = function(a0) {
 wrapper = { invoke(a0) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
Expand All@@ -279,13 +281,13 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 arg = getRawPointer(arg);
 }
 return rawFn(arg);
 };
 } }.invoke;
 } else if (nargs === 2) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 wrapper = function(a0, a1) {
 wrapper = { invoke(a0, a1) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
Expand All@@ -299,15 +301,15 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else if (nargs === 3) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const c2 = ArrayPrototypeIncludes(indexes, 2);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 const t2 = argumentTypes[2];
 wrapper = function(a0, a1, a2) {
 wrapper = { invoke(a0, a1, a2) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
Expand All@@ -323,9 +325,9 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else {
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 throwIfFastLibraryClosed(state);
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
Expand All@@ -349,7 +351,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 }

 return inheritMetadata(wrapper, rawFn, nargs);
Expand Down

11 changes: 8 additions & 3 deletions
src/node_ffi.cc

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -324,7 +324,9 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 maybe_ret = Function::New(context,
 use_sb ? DynamicLibrary::InvokeFunctionSB
 : DynamicLibrary::InvokeFunction,
 info->object());
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow);
 }

 Local<Function> ret;
Expand DownExpand Up@@ -377,8 +379,11 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 // (strings, Buffers, ArrayBuffers, and ArrayBufferViews).
 if (has_ptr_args) {
 Local<Function> slow_fn;
 if (!Function::New(
 context, DynamicLibrary::InvokeFunction, info->object())
 if (!Function::New(context,
 DynamicLibrary::InvokeFunction,
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow)
 .ToLocal(&slow_fn)) {
 return MaybeLocal<Function>();
 }
Expand Down

21 changes: 21 additions & 0 deletions
test/ffi/test-ffi-dynamic-library.js

View file


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Original file line numberDiff line numberDiff line change
Expand Up@@ -67,6 +67,27 @@ test('dlopen resolves functions from definitions', () => {
 }
});

test('FFI functions are not constructible', () => {
 const { lib, functions } = ffi.dlopen(libraryPath, {
 add_i32: fixtureSymbols.add_i32,
 multiply_f64: fixtureSymbols.multiply_f64,
 });

 try {
 assert.strictEqual(Object.hasOwn(functions.add_i32, 'prototype'), false);
 assert.strictEqual(
 Object.hasOwn(functions.multiply_f64, 'prototype'), false);
 assert.throws(
 () => Reflect.construct(functions.add_i32, [20, 22]),
 TypeError);
 assert.throws(
 () => Reflect.construct(functions.multiply_f64, [6, 7]),
 TypeError);
 } finally {
 lib.close();
 }
});

test('DynamicLibrary exposes functions and symbols', () => {
 const lib = new ffi.DynamicLibrary(libraryPath);

Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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Aug 17, 2026

+75

−45

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ffi: keep FFI functions non-constructible
#65184
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70 changes: 36 additions & 34 deletions
lib/internal/ffi-shared-buffer.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -198,6 +198,8 @@ function inheritMetadata(wrapper, rawFn, nargs) {
// arguments out of it into invocation-local storage before `ffi_call` and
// reads the return value back only after, so nested/reentrant calls into
// the same function are safe.
// Concise methods do not have [[Construct]], unlike function expressions, so
// use them below to match the native FFI functions' non-constructible behavior.
function wrapWithSharedBuffer(rawFn, signature) {
 if (rawFn == null) return rawFn;
 const buffer = rawFn[kSbSharedBuffer];
Expand DownExpand Up@@ -254,7 +256,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 // so arity specialization wouldn't buy much here.
 assert(slowInvoke !== undefined,
 'FFI: shared-buffer raw function with pointer arguments is missing kSbInvokeSlow');
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -271,7 +273,7 @@ function wrapWithSharedBuffer(rawFn, signature) {
 }
 rawFn();
 return retGetter === null ? undefined : retGetter(view, 0, true);
 };
 } }.invoke;
 } else {
 // Arity specialization avoids the per-call `Array` allocation of
 // `...args`; the void/non-void split removes a per-call branch on
Expand All@@ -295,67 +297,67 @@ function buildNumericWrapper(
 /* c8 ignore start */
 if (nargs === 0) {
 if (retGetter === null) {
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function() {
 return { invoke() {
 if (arguments.length !== 0) {
 throwFFIArgCountError(0, arguments.length);
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 /* c8 ignore stop */
 if (nargs === 1) {
 const i0 = argInfos[0];
 const o0 = argOffsets[0];
 if (retGetter === null) {
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0) {
 return { invoke(a0) {
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 2) {
 const i0 = argInfos[0];
 const i1 = argInfos[1];
 const o0 = argOffsets[0];
 const o1 = argOffsets[1];
 if (retGetter === null) {
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1) {
 return { invoke(a0, a1) {
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 3) {
 const i0 = argInfos[0];
Expand All@@ -365,17 +367,17 @@ function buildNumericWrapper(
 const o1 = argOffsets[1];
 const o2 = argOffsets[2];
 if (retGetter === null) {
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
 writeNumericArg(view, i0, o0, a0, 0);
 writeNumericArg(view, i1, o1, a1, 1);
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2) {
 return { invoke(a0, a1, a2) {
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
 }
Expand All@@ -384,7 +386,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 4) {
 const i0 = argInfos[0];
Expand All@@ -396,7 +398,7 @@ function buildNumericWrapper(
 const o2 = argOffsets[2];
 const o3 = argOffsets[3];
 if (retGetter === null) {
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -405,9 +407,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i2, o2, a2, 2);
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3) {
 return { invoke(a0, a1, a2, a3) {
 if (arguments.length !== 4) {
 throwFFIArgCountError(4, arguments.length);
 }
Expand All@@ -417,7 +419,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 5) {
 const i0 = argInfos[0];
Expand All@@ -431,7 +433,7 @@ function buildNumericWrapper(
 const o3 = argOffsets[3];
 const o4 = argOffsets[4];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -441,9 +443,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i3, o3, a3, 3);
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4) {
 return { invoke(a0, a1, a2, a3, a4) {
 if (arguments.length !== 5) {
 throwFFIArgCountError(5, arguments.length);
 }
Expand All@@ -454,7 +456,7 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 if (nargs === 6) {
 const i0 = argInfos[0];
Expand All@@ -470,7 +472,7 @@ function buildNumericWrapper(
 const o4 = argOffsets[4];
 const o5 = argOffsets[5];
 if (retGetter === null) {
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -481,9 +483,9 @@ function buildNumericWrapper(
 writeNumericArg(view, i4, o4, a4, 4);
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 };
 } }.invoke;
 }
 return function(a0, a1, a2, a3, a4, a5) {
 return { invoke(a0, a1, a2, a3, a4, a5) {
 if (arguments.length !== 6) {
 throwFFIArgCountError(6, arguments.length);
 }
Expand All@@ -495,22 +497,22 @@ function buildNumericWrapper(
 writeNumericArg(view, i5, o5, a5, 5);
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
 }
 // 7+ args: further specialization is diminishing returns and bloats
 // this builder.
 if (retGetter === null) {
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
 for (let i = 0; i < nargs; i++) {
 writeNumericArg(view, argInfos[i], argOffsets[i], args[i], i);
 }
 rawFn();
 };
 } }.invoke;
 }
 return function(...args) {
 return { invoke(...args) {
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
 }
Expand All@@ -519,7 +521,7 @@ function buildNumericWrapper(
 }
 rawFn();
 return retGetter(view, 0, true);
 };
 } }.invoke;
}

module.exports = {
Expand Down

18 changes: 10 additions & 8 deletions
lib/internal/ffi/fast-api.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -222,6 +222,8 @@ function throwIfFastLibraryClosed(state) {
 }
}

// Concise methods do not have [[Construct]], unlike function expressions.
// Keep wrappers non-constructible to match the native FFI functions.
function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 if (rawFn === undefined || rawFn === null) {
 return rawFn;
Expand DownExpand Up@@ -255,7 +257,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 const memory0 = needsRawPointerConversion(t0) || string0;
 const fastBufferInvoke = needsPointerLikeConversion(t0) ?
 rawFn[kFastBufferInvoke] : undefined;
 wrapper = function(a0) {
 wrapper = { invoke(a0) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 1) {
 throwFFIArgCountError(1, arguments.length);
Expand All@@ -279,13 +281,13 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 arg = getRawPointer(arg);
 }
 return rawFn(arg);
 };
 } }.invoke;
 } else if (nargs === 2) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 wrapper = function(a0, a1) {
 wrapper = { invoke(a0, a1) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 2) {
 throwFFIArgCountError(2, arguments.length);
Expand All@@ -299,15 +301,15 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else if (nargs === 3) {
 const c0 = ArrayPrototypeIncludes(indexes, 0);
 const c1 = ArrayPrototypeIncludes(indexes, 1);
 const c2 = ArrayPrototypeIncludes(indexes, 2);
 const t0 = argumentTypes[0];
 const t1 = argumentTypes[1];
 const t2 = argumentTypes[2];
 wrapper = function(a0, a1, a2) {
 wrapper = { invoke(a0, a1, a2) {
 throwIfFastLibraryClosed(state);
 if (arguments.length !== 3) {
 throwFFIArgCountError(3, arguments.length);
Expand All@@ -323,9 +325,9 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 } else {
 wrapper = function(...args) {
 wrapper = { invoke(...args) {
 throwIfFastLibraryClosed(state);
 if (args.length !== nargs) {
 throwFFIArgCountError(nargs, args.length);
Expand All@@ -349,7 +351,7 @@ function wrapWithRawPointerConversions(rawFn, argumentTypes, owner) {
 } finally {
 if (stringCall) exitStringConversion(stringState);
 }
 };
 } }.invoke;
 }

 return inheritMetadata(wrapper, rawFn, nargs);
Expand Down

11 changes: 8 additions & 3 deletions
src/node_ffi.cc

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -324,7 +324,9 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 maybe_ret = Function::New(context,
 use_sb ? DynamicLibrary::InvokeFunctionSB
 : DynamicLibrary::InvokeFunction,
 info->object());
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow);
 }

 Local<Function> ret;
Expand DownExpand Up@@ -377,8 +379,11 @@ MaybeLocal<Function> DynamicLibrary::CreateFunction(
 // (strings, Buffers, ArrayBuffers, and ArrayBufferViews).
 if (has_ptr_args) {
 Local<Function> slow_fn;
 if (!Function::New(
 context, DynamicLibrary::InvokeFunction, info->object())
 if (!Function::New(context,
 DynamicLibrary::InvokeFunction,
 info->object(),
 0,
 v8::ConstructorBehavior::kThrow)
 .ToLocal(&slow_fn)) {
 return MaybeLocal<Function>();
 }
Expand Down

21 changes: 21 additions & 0 deletions
test/ffi/test-ffi-dynamic-library.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -67,6 +67,27 @@ test('dlopen resolves functions from definitions', () => {
 }
});

test('FFI functions are not constructible', () => {
 const { lib, functions } = ffi.dlopen(libraryPath, {
 add_i32: fixtureSymbols.add_i32,
 multiply_f64: fixtureSymbols.multiply_f64,
 });

 try {
 assert.strictEqual(Object.hasOwn(functions.add_i32, 'prototype'), false);
 assert.strictEqual(
 Object.hasOwn(functions.multiply_f64, 'prototype'), false);
 assert.throws(
 () => Reflect.construct(functions.add_i32, [20, 22]),
 TypeError);
 assert.throws(
 () => Reflect.construct(functions.multiply_f64, [6, 7]),
 TypeError);
 } finally {
 lib.close();
 }
});

test('DynamicLibrary exposes functions and symbols', () => {
 const lib = new ffi.DynamicLibrary(libraryPath);

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