grab bag of small UB fixes #2298
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| @@ -20,7 +24,11 @@ struct config { | |||
| // libtester disables the limits in all tests, except enforces the limits | |||
| // in the tests in unittests/eosvmoc_limits_tests.cpp. | |||
| std::optional<rlim_t> cpu_limit {20u}; | |||
| #if __has_feature(undefined_behavior_sanitizer) || __has_feature(address_sanitizer) | |||
| std::optional<rlim_t> vm_limit; // UBSAN & ASAN can add massive virtual memory usage; don't enforce vm limits when either of them are enabled | |||
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Don't need this for tests to pass: OC in unit tests always has vm_limit disabled now (except for the one modified test case), and python integration tests never use OC. But I'd like to use OC + ASAN/UBSAN with nodeos. Such usage is probably "developer enough" where simply disabling this limit is safe when configured that way; i.e. won't trap unsuspecting users. Alternatively could guard this disablement behind EOSVMOC_ENABLE_DEVELOPER_OPTIONS but ultimately I want to remove that option.
| @@ -40,7 +40,7 @@ memory::memory(uint64_t sliced_pages) { | |||
| uintptr_t* const intrinsic_jump_table = reinterpret_cast<uintptr_t* const>(zeropage_base - first_intrinsic_offset); | |||
| const intrinsic_map_t& intrinsics = get_intrinsic_map(); | |||
| for(const auto& intrinsic : intrinsics) | |||
| intrinsic_jump_table[-intrinsic.second.ordinal] = (uintptr_t)intrinsic.second.function_ptr; | |||
| intrinsic_jump_table[-(int)intrinsic.second.ordinal] = (uintptr_t)intrinsic.second.function_ptr; | |||
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This is an interesting one. The error here gets reported somewhat confusingly as addition of unsigned offset to 0x7aca262015f8 overflowed to 0x7aca26201570. I believe what is occurring is that ordinal is a size_t thus uint64_t, and negating it is still a uint64_t: now a really large uint64_t. But pointer arithmetic is defined on integer math; ptrdiff_t is a signed integer for example. So I think this is causing some sort of wrap around on a large signed integer. Casting ordinal to an int before the negation ensures it remains a small value int before pointer arithmetic. I'd be curious on other takes though.
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Should this use intptr_t (long int) instead of int?
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ordinal is the host function index over in,
so
int will always be plenty large enough (we won't have 231 host functions). My initial impression of intptr_t is that its purpose/connotation isn't really for indexes in to an array.
I do wonder if ordinal should just be an int instead; I don't think it'd be too hard to change it.
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whoops, I pushed b47a64c here to the wrong branch; I wanted to have a separate PR for that. Sorry for force pushing it away... |
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Note:start |
Brings in,
AntelopeIO/abieos#25
AntelopeIO/appbase#31
AntelopeIO/bn256#20
AntelopeIO/eos-vm#22
along with some other noted changes below.