Merge branch 'master' into merge

.github/workflows/benchmark.yml

@@ -13,9 +13,7 @@ on:
 
 jobs:
   callgrind:
-    name: callgrind
     strategy:
-      fail-fast: false
       matrix:
         os: [ubuntu-22.04]
         benchResultsRepo:
@@ -44,9 +42,9 @@ jobs:
         run: |
           python bench/bench.py --callgrind --vm "./luau-gcc -O2" | tee -a bench-gcc-output.txt
 
-      - name: Run benchmark (bench-clang)
+      - name: Run benchmark (bench)
         run: |
-          python bench/bench.py --callgrind --vm "./luau -O2" | tee -a bench-clang-output.txt
+          python bench/bench.py --callgrind --vm "./luau -O2" | tee -a bench-output.txt
 
       - name: Run benchmark (analyze)
         run: |
@@ -78,13 +76,13 @@ jobs:
           token: ${{ secrets.BENCH_GITHUB_TOKEN }}
           path: "./gh-pages"
 
-      - name: Store results (bench-clang)
+      - name: Store results (bench)
         uses: Roblox/rhysd-github-action-benchmark@v-luau
         with:
           name: callgrind clang
           tool: "benchmarkluau"
-          output-file-path: ./bench-clang-output.txt
-          external-data-json-path: ./gh-pages/bench-clang.json
+          output-file-path: ./bench-output.txt
+          external-data-json-path: ./gh-pages/bench.json
 
       - name: Store results (bench-gcc)
         uses: Roblox/rhysd-github-action-benchmark@v-luau

VM/src/lapi.cpp

@@ -1209,7 +1209,10 @@ void* lua_newuserdatadtor(lua_State* L, size_t sz, void (*dtor)(void*))
 {
     luaC_checkGC(L);
     luaC_checkthreadsleep(L);
-    Udata* u = luaU_newudata(L, sz + sizeof(dtor), UTAG_IDTOR);
+    size_t as = sz + sizeof(dtor);
+    if (as < sizeof(dtor))
+        as = SIZE_MAX; // Will cause a memory error in luaU_newudata.
+    Udata* u = luaU_newudata(L, as, UTAG_IDTOR);
     memcpy(&u->data + sz, &dtor, sizeof(dtor));
     setuvalue(L, L->top, u);
     api_incr_top(L);

docs/_pages/compatibility.md

@@ -70,6 +70,7 @@ Sandboxing challenges are [covered in the dedicated section](sandbox).
 | `bit32` library | ✔️ | |
 | `string.gsub` is stricter about using `%` on special characters only | ✔️ | |
 | light C functions | 😞 | this changes semantics of fenv on C functions and has complex implications wrt runtime performance |
+| NaN keys are supported for tables with `__newindex` | ✔️ | |
 
 Two things that are important to call out here are various new metamethods for tables and yielding in metamethods. In both cases, there are performance implications to supporting this - our implementation is *very* highly tuned for performance, so any changes that affect the core fundamentals of how Lua works have a price. To support yielding in metamethods we'd need to make the core of the VM more involved, since almost every single "interesting" opcode would need to learn how to be resumable - which also complicates future JIT/AOT story. Metamethods in general are important for extensibility, but very challenging to deal with in implementation, so we err on the side of not supporting any new metamethods unless a strong need arises.
 

docs/_pages/lint.md

@@ -326,7 +326,6 @@ Luau uses comments that start from `!` to control certain aspects of analysis, f
 --!nostrict
 -- Unknown comment directive 'nostrict'; did you mean 'nonstrict'?"
 ```
-```
 
 ## IntegerParsing (27)
 

rfcs/generalized-iteration.md

@@ -51,8 +51,10 @@ end
 To support self-iterating objects, we modify the iteration protocol as follows: instead of simply expanding the result of expression `iter` into three variables (`gen`, `state` and `index`), we check if the first result has an `__iter` metamethod (which can be the case if it's a table, userdata or another composite object (e.g. a record in the future). If it does, the metamethod is called with `gen` as the first argument, and the returned three values replace `gen`/`state`/`index`. This happens *before* the loop:
 
 ```lua
-if getmetatable(gen) and getmetatable(gen).__iter then
-   gen, state, index = getmetatable(gen).__iter(gen)
+local genmt = rawgetmetatable(gen) -- pseudo code for getmetatable that bypasses __metatable
+local iterf = genmt and rawget(genmt, "__iter")
+if iterf then
+   gen, state, index = iterf(gen)
 end
 ```
 

tests/Conformance.test.cpp

@@ -716,6 +716,23 @@ TEST_CASE("Reference")
     CHECK(dtorhits == 2);
 }
 
+TEST_CASE("NewUserdataOverflow")
+{
+    StateRef globalState(luaL_newstate(), lua_close);
+    lua_State* L = globalState.get();
+
+    lua_pushcfunction(L, [](lua_State* L1) {
+        // The following userdata request might cause an overflow.
+        lua_newuserdatadtor(L1, SIZE_MAX, [](void* d){});
+        // The overflow might segfault in the following call.
+        lua_getmetatable(L1, -1);
+        return 0;
+    }, "PCall");
+
+    CHECK(lua_pcall(L, 0, 0, 0) == LUA_ERRRUN);
+    CHECK(strcmp(lua_tostring(L, -1), "memory allocation error: block too big") == 0);
+}
+
 TEST_CASE("ApiTables")
 {
     StateRef globalState(luaL_newstate(), lua_close);