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dump: always allocate >=8 bytes for multibit

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The multibit runtime assumes that it is always safe to read 8 bytes, so
we must over-allocate for smaller sizes. Caught by ASan.
This commit is contained in:
Justin Viiret 2017-05-31 13:07:22 +10:00 committed by Matthew Barr
parent 85f7790a21
commit bdae3d5b80
1 changed files with 10 additions and 3 deletions
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13
src/rose/rose_build_dump.cpp
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@ -681,10 +681,17 @@ vector<u32> sparseIterValues(const mmbit_sparse_iter *it, u32 num_bits) {
return keys; return keys;
} }
vector<u8> bits(mmbit_size(num_bits), u8{0xff}); // All bits on. // Populate a multibit structure with all-ones. Note that the multibit
vector<mmbit_sparse_state> state(MAX_SPARSE_ITER_STATES); // runtime assumes that it is always safe to read 8 bytes, so we must
// over-allocate for smaller sizes.
const size_t num_bytes = mmbit_size(num_bits);
vector<u8> bits(max(size_t{8}, num_bytes), u8{0xff}); // All bits on.
const u8 *b = bits.data(); const u8 *b = bits.data();
if (num_bytes < 8) {
b += 8 - num_bytes;
}
vector<mmbit_sparse_state> state(MAX_SPARSE_ITER_STATES);
mmbit_sparse_state *s = state.data(); mmbit_sparse_state *s = state.data();
u32 idx = 0; u32 idx = 0;