[pull] main from oven-sh:main - #30
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<details> <summary> observed in https://buildkite.com/bun/bun/builds/22442#annotation-test/js/node/zlib/leak.test.ts </summary> ``` ==5045==ERROR: AddressSanitizer: heap-use-after-free on address 0x5220000243c0 at pc 0x00000dad671b bp 0x14f22d4a4990 sp 0x14f22d4a4988 READ of size 8 at 0x5220000243c0 thread T5 (HeapHelper) ======== Stack trace from GDB for HeapHelper-5045.core: ======== Program terminated with signal SIGABRT, Aborted. #0 0x000014f2c3672eec in ?? () from /lib/x86_64-linux-gnu/libc.so.6 [Current thread is 1 (Thread 0x14f22d4f46c0 (LWP 5050))] #0 0x000014f2c3672eec in ?? () from /lib/x86_64-linux-gnu/libc.so.6 #1 0x000014f2c3623fb2 in raise () from /lib/x86_64-linux-gnu/libc.so.6 #2 0x000014f2c360e472 in abort () from /lib/x86_64-linux-gnu/libc.so.6 #3 0x000000000e3b2ae2 in uw_init_context_1[cold] () #4 0x000000000e3b29fc in _Unwind_Backtrace () #5 0x00000000046a6bab in __sanitizer::BufferedStackTrace::UnwindSlow(unsigned long, unsigned int) () #6 0x00000000046a181d in __sanitizer::BufferedStackTrace::Unwind(unsigned int, unsigned long, unsigned long, void*, unsigned long, unsigned long, bool) () #7 0x00000000046885bd in __sanitizer::BufferedStackTrace::UnwindImpl(unsigned long, unsigned long, void*, bool, unsigned int) () #8 0x0000000004601127 in __asan::ErrorGeneric::Print() () #9 0x0000000004683180 in __asan::ScopedInErrorReport::~ScopedInErrorReport() () #10 0x0000000004686567 in __asan::ReportGenericError(unsigned long, unsigned long, unsigned long, unsigned long, bool, unsigned long, unsigned int, bool) () #11 0x0000000004686d46 in __asan_report_load8 () #12 0x000000000dad671b in ZSTD_sizeof_CCtx (cctx=<optimized out>) at ./build/release-asan/zstd/vendor/zstd/lib/compress/zstd_compress.c:210 #13 0x0000000006d2284d in bun.js.node.zlib.NativeZstd.estimatedSize () at /var/lib/buildkite-agent/builds/ip-172-31-72-121/bun/bun/src/bun.js/node/zlib/NativeZstd.zig:57 #14 ZigGeneratedClasses.JSNativeZstd.JavaScriptCoreBindings.NativeZstd__estimatedSize (thisValue=<optimized out>) at /var/lib/buildkite-agent/builds/ip-172-31-72-121/bun/bun/build/release-asan/codegen/ZigGeneratedClasses.zig:11122 #15 0x000000000852803b in WebCore::JSNativeZstd::visitChildrenImpl<JSC::SlotVisitor> (cell=0x14f22e190840, visitor=...) at ./build/release-asan/./build/release-asan/codegen/ZigGeneratedClasses.cpp:30728 #16 WebCore::JSNativeZstd::visitChildren (cell=0x14f22e190840, visitor=...) at ./build/release-asan/./build/release-asan/codegen/ZigGeneratedClasses.cpp:30734 #17 0x000000000aa99d6c in JSC::MethodTable::visitChildren (this=<optimized out>, cell=<optimized out>, visitor=...) at vendor/WebKit/Source/JavaScriptCore/runtime/ClassInfo.h:115 #18 0x000000000aa99d6c in JSC::SlotVisitor::visitChildren (this=0x14f277028300, cell=0x14f22e190840) #19 JSC::SlotVisitor::drain(WTF::MonotonicTime)::$_0::operator()(JSC::MarkStackArray&) const (this=<optimized out>, stack=...) at vendor/WebKit/Source/JavaScriptCore/heap/SlotVisitor.cpp:509 #20 0x000000000aa8f130 in JSC::SlotVisitor::forEachMarkStack<JSC::SlotVisitor::drain(WTF::MonotonicTime)::$_0>(JSC::SlotVisitor::drain(WTF::MonotonicTime)::$_0 const&) (this=0x14f277028300, func=...) at vendor/WebKit/Source/JavaScriptCore/heap/SlotVisitorInlines.h:193 #21 JSC::SlotVisitor::drain (this=this@entry=0x14f277028300, timeout=<error reading variable: That operation is not available on integers of more than 8 bytes.>, timeout@entry=...) at vendor/WebKit/Source/JavaScriptCore/heap/SlotVisitor.cpp:499 #22 0x000000000aa90590 in JSC::SlotVisitor::drainFromShared (this=0x14f277028300, sharedDrainMode=JSC::SlotVisitor::HelperDrain, timeout=<error reading variable: That operation is not available on integers of more than 8 bytes.>) at vendor/WebKit/Source/JavaScriptCore/heap/SlotVisitor.cpp:699 #23 0x000000000aa08726 in JSC::Heap::runBeginPhase(JSC::GCConductor)::$_1::operator()() const (this=<optimized out>) at vendor/WebKit/Source/JavaScriptCore/heap/Heap.cpp:1508 #24 WTF::SharedTaskFunctor<void (), JSC::Heap::runBeginPhase(JSC::GCConductor)::$_1>::run() (this=<optimized out>) at .WTF/Headers/wtf/SharedTask.h:91 #25 0x000000000aa3b596 in WTF::ParallelHelperClient::runTask(WTF::RefPtr<WTF::SharedTask<void ()>, WTF::RawPtrTraits<WTF::SharedTask<void ()> >, WTF::DefaultRefDerefTraits<WTF::SharedTask<void ()> > > const&) (this=0x14f22e000428, task=...) at vendor/WebKit/Source/WTF/wtf/ParallelHelperPool.cpp:110 #26 0x000000000aa3d976 in WTF::ParallelHelperPool::Thread::work (this=<optimized out>) at vendor/WebKit/Source/WTF/wtf/ParallelHelperPool.cpp:201 #27 0x000000000aa4210d in WTF::AutomaticThread::start(WTF::AbstractLocker const&)::$_0::operator()() const (this=<optimized out>) at vendor/WebKit/Source/WTF/wtf/AutomaticThread.cpp:225 #28 WTF::Detail::CallableWrapper<WTF::AutomaticThread::start(WTF::AbstractLocker const&)::$_0, void>::call() (this=<optimized out>) at vendor/WebKit/Source/WTF/wtf/Function.h:53 #29 0x0000000008958ada in WTF::Function<void ()>::operator()() const (this=<optimized out>) at vendor/WebKit/Source/WTF/wtf/Function.h:82 #30 WTF::Thread::entryPoint (newThreadContext=<optimized out>) at vendor/WebKit/Source/WTF/wtf/Threading.cpp:272 #31 0x0000000008a65689 in WTF::wtfThreadEntryPoint (context=0x13b5) at vendor/WebKit/Source/WTF/wtf/posix/ThreadingPOSIX.cpp:255 #32 0x000000000467d347 in asan_thread_start(void*) () #33 0x000014f2c36711f5 in ?? () from /lib/x86_64-linux-gnu/libc.so.6 #34 0x000014f2c36f189c in ?? () from /lib/x86_64-linux-gnu/libc.so.6 ``` </details> `ZSTD_sizeof_CCtx` and `ZSTD_sizeof_DCtx` can not be relied upon to be thread-safe and estimatedSize may be called from any thread
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…to prevent UAF (oven-sh#30057) ## What `UDPSocket.sendMany()` and `UDPSocket.send()` both captured raw pointers into the payload's ArrayBuffer backing store (or borrowed `WTFStringImpl` storage for Latin-1 strings) and then hit JSC safepoints before handing those pointers to `bsd_sendmmsg`: - **`sendMany`**: subsequent loop iterations call `iter.next()` (slow path → `JSObject.getIndex`), `coerceToInt32` on the port, and `toBunString` on the address - **`send`**: `parseAddr` calls `coerceToInt32` on the port and `toBunString` on the address after the payload is captured Any of these can run user JS that detaches an earlier payload's ArrayBuffer via `.transfer(newLen)` (which synchronously frees the old backing store) or drops the last reference to a JSString, leaving the captured pointer dangling. ## Repro ```js const buf = new ArrayBuffer(4096); const payload = new Uint8Array(buf); const evilPort = { valueOf() { buf.transfer(0); // synchronously frees the 4096-byte backing store return server.port; }, }; client.sendMany([payload, evilPort, "127.0.0.1"]); // or client.send(payload, evilPort, "127.0.0.1") // bsd_sendmmsg reads 4096 bytes from the freed region ``` Under ASAN (with `Malloc=1` so bmalloc routes through the system heap): ``` ==…==ERROR: AddressSanitizer: heap-use-after-free on address … at pc … READ of size 4096 at … thread T0 #0 … in read_iovec(…) #2 … in sendmmsg #3 … in bsd_sendmmsg packages/bun-usockets/src/bsd.c:123 freed by thread T0 here: … #14 … in JSC::arrayBufferCopyAndDetach(…) JSArrayBufferPrototype.cpp:365 … #30 … in JSC::JSValue::toInt32(…) ← parseAddr's coerceToInt32 ``` ## Fix - **`sendMany`**: root every payload JSValue in a `MarkedArgumentBuffer` for the duration of the call and split the loop into two phases. Phase 1 collects/validates payload JSValues and runs all user-JS re-entrance (`iter.next`, `parseAddr`). Phase 2 borrows byte slices from the rooted JSValues once no more user JS sits between capture and `socket.send`. GC cannot collect a rooted payload; an ArrayBuffer that was detached during phase 1 reports a zero-length slice instead of a dangling pointer. No payload bytes are copied. - **`send`**: reorder so `parseAddr` runs before the payload pointer is captured. `payload_arg` stays rooted in the callframe, and nothing between capture and `socket.send` hits a JSC safepoint — so no copy is needed. ## Verification - **Without fix:** `bun bd test test/js/bun/udp/udp_socket.test.ts -t 'detaching an ArrayBuffer'` → ASAN heap-use-after-free in `read_iovec` → `bsd_sendmmsg` for both `send` and `sendMany`, tests fail - **With fix:** both tests pass; received bytes match the original payload - Full `test/js/bun/udp/` suite (207 tests) passes - `zig:check-all` passes on all targets --------- Co-authored-by: robobun <robobun@users.noreply.github.com> Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
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