Fix use-after-free in externref example #8410
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This fixes a typo in the `externref.c` example where a deallocated `wasmtime_val_t` was used by accident. Additionally this introduces scoping to prevent this from arising again.
fitzgen
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Apr 19, 2024
examples/externref.c
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| assert(item.kind == WASMTIME_EXTERN_TABLE); | ||
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| // Set `table[3]` to our `externref`. | ||
| wasmtime_val_t externref_val; |
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This is now declared inside this block, but then reused in the other block and has wasmtime_val_delete called outside of the block. Can we move it up, out of this block then?
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Wait what how does this compile given this mistake...
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Ah the answer is that it doesn't...
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lol yeah I was wondering myself
alexcrichton
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* Fix use-after-free in externref example This fixes a typo in the `externref.c` example where a deallocated `wasmtime_val_t` was used by accident. Additionally this introduces scoping to prevent this from arising again. * Run clang-format * Fix compilation of C example
fitzgen
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Apr 19, 2024
* Fix use-after-free in externref example This fixes a typo in the `externref.c` example where a deallocated `wasmtime_val_t` was used by accident. Additionally this introduces scoping to prevent this from arising again. * Run clang-format * Fix compilation of C example
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This fixes a typo in the
externref.cexample where a deallocatedwasmtime_val_twas used by accident. Additionally this introduces scoping to prevent this from arising again.