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Account for fuel before unconditionally trapping Wasm accesses (#5447)

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* Account for fuel before unconditionally trapping Wasm accesses

Fixes #5445

* Add a test for fuel accounting and unconditionally trapping memory accesses
This commit is contained in:
Nick Fitzgerald
2022-12-15 12:18:52 -08:00
committed by GitHub
parent 0a6a28a4fb
commit 1fe56d7efb
5 changed files with 80 additions and 15 deletions
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16
cranelift/wasm/src/code_translator.rs
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@@ -2316,17 +2316,18 @@ where
// offsets in `memarg` are <=2gb, which means we get the fast path of one
// `heap_addr` instruction plus a hardcoded i32-offset in memory-related
// instructions.
let heap = environ.heaps()[heap].clone();
let addr = match u32::try_from(memarg.offset) {
// If our offset fits within a u32, then we can place the it into the
// offset immediate of the `heap_addr` instruction.
Ok(offset) => bounds_checks::bounds_check_and_compute_addr(
builder,
&*environ,
&environ.heaps()[heap],
environ,
&heap,
index,
offset,
access_size,
),
)?,
// If the offset doesn't fit within a u32, then we can't pass it
// directly into `heap_addr`.
@@ -2355,20 +2356,19 @@ where
// relatively odd/rare. In the future if needed we can look into
// optimizing this more.
Err(_) => {
let index_type = environ.heaps()[heap].index_type;
let offset = builder.ins().iconst(index_type, memarg.offset as i64);
let offset = builder.ins().iconst(heap.index_type, memarg.offset as i64);
let adjusted_index =
builder
.ins()
.uadd_overflow_trap(index, offset, ir::TrapCode::HeapOutOfBounds);
bounds_checks::bounds_check_and_compute_addr(
builder,
&*environ,
&environ.heaps()[heap],
environ,
&heap,
adjusted_index,
0,
access_size,
)
)?
}
};
let addr = match addr {