Open multiple architectures with same offsets

hqtsm · Jan 19, 2025 · 904e4a5 · 904e4a5
1 parent 09e2be5
commit 904e4a5
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Showing 2 changed files with 30 additions and 2 deletions.
diff --git a/macho/universal.test.ts b/macho/universal.test.ts
@@ -127,7 +127,7 @@ Deno.test('open under arch', async () => {
 Deno.test('open under count archs', async () => {
 	const data = new ArrayBuffer(
 		Math.max(FatHeader.BYTE_LENGTH, MachHeader.BYTE_LENGTH) +
-			FatArch.BYTE_LENGTH + 512,
+			FatArch.BYTE_LENGTH * 2 + 512,
 	);
 	const header = new FatHeader(data);
 	header.magic = FAT_MAGIC;
@@ -152,6 +152,32 @@ Deno.test('open under count archs', async () => {
 	assertEquals(archs.size, 2);
 });
 
+Deno.test('open duplicate offset', async () => {
+	const data = new ArrayBuffer(
+		Math.max(FatHeader.BYTE_LENGTH, MachHeader.BYTE_LENGTH) +
+			FatArch.BYTE_LENGTH * 2,
+	);
+	const header = new FatHeader(data);
+	header.magic = FAT_MAGIC;
+	header.nfatArch = 2;
+
+	const arch1 = new FatArch(data, header.byteLength);
+	arch1.offset = data.byteLength;
+	arch1.size = 0;
+
+	const arch2 = new FatArch(data, arch1.byteOffset + arch1.byteLength);
+	arch2.offset = data.byteLength;
+	arch2.size = 0;
+
+	const blob = new Blob([data]);
+	const uni = new Universal();
+	await assertRejects(
+		() => uni.open(blob),
+		RangeError,
+		`Multiple architectures at offset: 0x${data.byteLength.toString(16)}`,
+	);
+});
+
 Deno.test('typeOf under header', async () => {
 	const blob = new Blob([new ArrayBuffer(MachHeader.BYTE_LENGTH - 1)]);
 	assertEquals(await Universal.typeOf(blob), 0);

diff --git a/macho/universal.ts b/macho/universal.ts
@@ -148,7 +148,9 @@ export class Universal {
 				for (const { offset, size, align } of sortedList) {
 					if (mSizes.has(offset)) {
 						throw new RangeError(
-							`Two architectures have the same offset: ${offset}`,
+							`Multiple architectures at offset: 0x${
+								offset.toString(16)
+							}`,
 						);
 					}
 					mSizes.set(offset, size);