fix(libkernel): throw on a size-0 _umtx_op timeout that is not a valid timespec

core/libs/prx/libkernel/SyncOnAddress/src/SyncOnAddress.cpp

@@ -137,6 +137,9 @@ int UmtxDeadline(const void* sizeArgument, const void* timeArgument, std::option
         time = *static_cast<const UmtxTime*>(timeArgument);
     }
     if (time.timeout.tv_sec < 0 || time.timeout.tv_nsec < 0 || time.timeout.tv_nsec >= NANOS_PER_SECOND) {
+        if (sizeArgument == nullptr) {
+            NotImplemented_nid_no_patch("_umtx_op timeout with size argument 0 that is not a valid timespec");
+        }
         return GUEST_EINVAL;
     }
 

core/libs/tests/GuestUmtxOp.cpp

@@ -122,9 +122,19 @@ static void TimesOutWhileTheValueMatches() {
 static void RejectsAnInvalidTimeout() {
     std::uint32_t word = 1;
     KernelTimespec negative{-1, 0};
-    Require(FailsWith(Umtx(&word, UMTX_OP_WAIT_UINT, 1, nullptr, &negative), GUEST_EINVAL));
+    Require(FailsWith(Umtx(&word, UMTX_OP_WAIT_UINT, 1, SizeOf(sizeof(negative)), &negative), GUEST_EINVAL));
     KernelTimespec tooManyNanos{0, 1000000000};
-    Require(FailsWith(Umtx(&word, UMTX_OP_WAIT_UINT, 1, nullptr, &tooManyNanos), GUEST_EINVAL));
+    Require(FailsWith(Umtx(&word, UMTX_OP_WAIT_UINT, 1, SizeOf(sizeof(tooManyNanos)), &tooManyNanos), GUEST_EINVAL));
+    for (const int operation : {UMTX_OP_WAIT, UMTX_OP_WAIT_UINT}) {
+        bool threw = false;
+        try { Umtx(&word, operation, 1, nullptr, &tooManyNanos); }
+        catch (const std::runtime_error&) { threw = true; }
+        Require(threw);
+        threw = false;
+        try { Umtx(&word, operation, 1, nullptr, &negative); }
+        catch (const std::runtime_error&) { threw = true; }
+        Require(threw);
+    }
     UmtxTime negativeNanos{{0, -1}, 0, CLOCK_MONOTONIC_ID};
     Require(FailsWith(Umtx(&word, UMTX_OP_WAIT_UINT, 1, SizeOf(sizeof(negativeNanos)), &negativeNanos), GUEST_EINVAL));
 }

docs/dev/TechnicalDebt.md

@@ -166,7 +166,7 @@ Throughout the project, every function at every stage either **does exactly what
 - [sceKernelGetModuleInfo](../../core/libs/prx/libkernel/Module/src/ModuleInfo.cpp) (libkernel) - the 0x160-byte layout (`st_size`, `name[256]`, 4 segments, `segment_count`, `fingerprint[20]`) follows [fpPS4](https://github.com/red-prig/fpPS4/blob/04cefd43e6fddd1ab033e7980cd356d14c964905/sys/sys_types.pas#L319-L337) and [shadPS4](https://github.com/shadps4-emu/shadPS4/blob/0fe263a4760dfbfa973366890061749b4af0de97/src/core/module.h#L15-L31). Only that `st_size` is accepted, as in shadPS4; other sizes return `EINVAL`, a null pointer `EFAULT` and a handle `sceKernelGetModuleList` does not list `ESRCH`. Name and segments are the ones `sceKernelGetModuleInfoFromAddr` reports, on Windows from the same PE sections, so `prot` uses the read/write/execute bits 1/2/4, while fpPS4 and shadPS4 store the ELF `p_flags`. The fingerprint is left zero, as the host image does not carry it
 - [sceKernelReleaseFlexibleMemory](../../core/libs/prx/libkernel/DirectMemory/Export.cpp) (libkernel) - unmaps the range like sceKernelMunmap, as fpPS4 and prosper do; whether the console keeps the virtual range reserved after releasing its pages is unverified
 - [Memory protection bits 0x100 and 0x200](../../core/libs/prx/libkernel/DirectMemory/DirectMemory.cpp) (libkernel) - taken as audio coprocessor (ACP) read and write, as in the [KytyPS5](https://github.com/KytyPS5/KytyPS5) and [etaHEN](https://github.com/etaHEN/etaHEN) headers; the coprocessor work runs on the host CPU, so they grant host read and read/write access like the GPU bits
-- [_umtx_op](../../core/libs/prx/libkernel/SyncOnAddress/src/SyncOnAddress.cpp) (libkernel) - `UMTX_OP_WAIT`, `UMTX_OP_WAKE`, `UMTX_OP_WAIT_UINT`, `UMTX_OP_WAIT_UINT_PRIVATE` and `UMTX_OP_WAKE_PRIVATE` follow FreeBSD 11's [kern_umtx.c](https://github.com/freebsd/freebsd-src/blob/stable/11/sys/kern/kern_umtx.c): a timeout whose size argument is at most 16 is a relative `timespec`, a larger one an `_umtx_time`, and a wake of 0 or fewer wakes one waiter. Waiters share the queue of `sceKernelSyncOnAddressWait`. Operation 0 fails with `EOPNOTSUPP` and operations above 26 with `EINVAL`, as in FreeBSD 11; `UMTX_OP_WAIT_UINT` with a value that does not fit in 32 bits returns 0 at once, as FreeBSD's zero-extended compare does. Operation 1 throws, since PPSA12544's call_once uses it in a way FreeBSD rejects; the other operations throw, and so does a misaligned object. PPSA12544's `libc.prx` passes `UMTX_OP_WAIT` and `UMTX_OP_WAIT_UINT` a pointer to a 4-byte microsecond timeout with size argument 0, which FreeBSD reads as a `timespec`, and waits for a running call_once with operation 1; its `PS5Util.prx` passes a `timespec`. Whether the console reads a microsecond timeout there, and what operation 1 does on it, is unverified
+- [_umtx_op](../../core/libs/prx/libkernel/SyncOnAddress/src/SyncOnAddress.cpp) (libkernel) - `UMTX_OP_WAIT`, `UMTX_OP_WAKE`, `UMTX_OP_WAIT_UINT`, `UMTX_OP_WAIT_UINT_PRIVATE` and `UMTX_OP_WAKE_PRIVATE` follow FreeBSD 11's [kern_umtx.c](https://github.com/freebsd/freebsd-src/blob/stable/11/sys/kern/kern_umtx.c): a timeout whose size argument is at most 16 is a relative `timespec`, a larger one an `_umtx_time`, and a wake of 0 or fewer wakes one waiter. Waiters share the queue of `sceKernelSyncOnAddressWait`. Operation 0 fails with `EOPNOTSUPP` and operations above 26 with `EINVAL`, as in FreeBSD 11; `UMTX_OP_WAIT_UINT` with a value that does not fit in 32 bits returns 0 at once, as FreeBSD's zero-extended compare does. Operation 1 throws, since PPSA12544's call_once uses it in a way FreeBSD rejects; the other operations throw, and so does a misaligned object. PPSA12544's `libc.prx` passes `UMTX_OP_WAIT` and `UMTX_OP_WAIT_UINT` a pointer to a 4-byte microsecond timeout with size argument 0, which FreeBSD reads as a `timespec`, and waits for a running call_once with operation 1; its `PS5Util.prx` passes a `timespec`. Whether the console reads a microsecond timeout there, and what operation 1 does on it, is unverified. A libc call cannot be told apart from a `timespec` call by the size argument alone, so a timeout with size argument 0 is read as a `timespec` and only throws when it is not a valid one (negative seconds, nanoseconds outside [0, 1e9)), which is where FreeBSD would return `EINVAL`; a microsecond value that happens to read as a valid `timespec` is waited on as one
 - [sceKernelSyncOnAddressWait](../../core/libs/prx/libkernel/SyncOnAddress/src/SyncOnAddress.cpp) (libkernel) - the only known caller passes a null timeout and a name string as the fourth argument; the timeout is assumed to point to microseconds like the other kernel waits, and the name is ignored
 - [sceKernelSyncOnAddressWait8 / sceKernelSyncOnAddressWait16 / sceKernelSyncOnAddressWait32 / sceKernelSyncOnAddressWait64](../../core/libs/prx/libkernel/SyncOnAddress/src/SyncOnAddress.cpp) (libkernel) - libc's `__std_atomic_wait_direct_8/16/32/64` pass a microsecond timeout or null and ignore the result; the by-value comparand, return values and the 2- and 8-byte alignment of Wait16 and Wait64 are assumed
 - [scePthreadRwlockDestroy, pthread_rwlock_destroy](../../core/libs/prx/libkernel/Pthread/src/Rwlock.cpp) (libkernel) - a rwlock held for reading or writing returns `EBUSY` and keeps its handle, as [KytyPS5](https://github.com/KytyPS5/KytyPS5) does; FreeBSD's [libthr](https://github.com/freebsd/freebsd-src/blob/main/lib/libthr/thread/thr_rwlock.c) and shadPS4 free it without checking, and the console's answer is unverified. Destroying a rwlock while another thread is acquiring it is not guarded