diff --git a/doc/ext_ffi_semantics.html b/doc/ext_ffi_semantics.html index 3444b8fb..5415787d 100644 --- a/doc/ext_ffi_semantics.html +++ b/doc/ext_ffi_semantics.html @@ -1219,7 +1219,7 @@ suboptimal performance, especially when used in inner loops:
  • Table initializers.
  • Initialization of nested struct/union types.
  • Non-default initialization of VLA/VLS or large C types -(> 128 bytes or > 16 array elements.
    • +(> 128 bytes or > 16 array elements).
  • Bitfield initializations.
  • Pointer differences for element sizes that are not a power of two.
    • diff --git a/doc/extensions.html b/doc/extensions.html index cf57e0e8..68193187 100644 --- a/doc/extensions.html +++ b/doc/extensions.html @@ -408,7 +408,7 @@ the toolchain used to compile LuaJIT: Windows/x64 -MSVC or WinSDK +MSVC Full diff --git a/doc/faq.html b/doc/faq.html index 31d91e2b..5c4ce533 100644 --- a/doc/faq.html +++ b/doc/faq.html @@ -57,7 +57,7 @@ dd { margin-left: 1.5em; }
    -
    +
    Q: Where can I learn more about LuaJIT and Lua?
      @@ -77,7 +77,7 @@ has information about diverse topics.
    -
    +
    Q: Where can I learn more about the compiler technology used by LuaJIT?
    I'm planning to write more documentation about the internals of LuaJIT. @@ -93,7 +93,7 @@ And, you know, reading the source is of course the only way to enlightenment. :-
    -
    +
    Q: Why do I get this error: "attempt to index global 'arg' (a nil value)"?
    Q: My vararg functions fail after switching to LuaJIT!
    LuaJIT is compatible to the Lua 5.1 language standard. It doesn't @@ -103,7 +103,7 @@ functions from Lua 5.0.
    Please convert your code to the vararg syntax.
    -
    +
    Q: Why do I get this error: "bad FPU precision"?
    Q: I get weird behavior after initializing Direct3D.
    Q: Some FPU operations crash after I load a Delphi DLL.
    @@ -125,7 +125,7 @@ Please check the Delphi docs for the Set8087CW method.
    -
    +
    Q: Sometimes Ctrl-C fails to stop my Lua program. Why?
    The interrupt signal handler sets a Lua debug hook. But this is currently ignored by compiled code (this will eventually be fixed). If @@ -136,7 +136,31 @@ twice to get stop your program. That's similar to when it's stuck running inside a C function under the Lua interpreter.
    -
    +
    +
    Q: Can Lua code be safely sandboxed?
    +
    +Maybe for an extremly restricted subset of Lua and if you relentlessly +scrutinize every single interface function you offer to the untrusted code.
    + +Although Lua provides some sandboxing functionality (setfenv(), hooks), +it's very hard to get this right even for the Lua core libraries. Of course, +you'll need to inspect any extension library, too. And there are libraries +that are inherently unsafe, e.g. the FFI library.
    + +Relatedly, loading untrusted bytecode is not safe! It's trivial +to crash the Lua or LuaJIT VM with maliciously crafted bytecode. This is +well known and there's no bytecode verification on purpose, so please +don't report a bug about it. Check the mode parameter for the +load*() functions to disable loading of bytecode.
    + +In general, the only promising approach is to sandbox Lua code at the +process level and not the VM level.
    + +More reading material at the » Lua Wiki and Wikipedia. +
    +
    + +
    Q: Why doesn't my favorite power-patch for Lua apply against LuaJIT?
    Because it's a completely redesigned VM and has very little code in common with Lua anymore. Also, if the patch introduces changes to @@ -147,7 +171,7 @@ can use source transformations or use wrapper or proxy functions. The compiler will happily optimize away such indirections.
    -
    +
    Q: Lua runs everywhere. Why doesn't LuaJIT support my CPU?
    Because it's a compiler — it needs to generate native machine code. This means the code generator must be ported to each @@ -158,7 +182,7 @@ architectures. Other architectures will follow based on sufficient user demand and/or sponsoring.
    -
    +
    Q: When will feature X be added? When will the next version be released?
    When it's ready.
    C'mon, it's open source — I'm doing it on my own time and you're