Fix GH-16054: Segmentation fault when resizing hash table iterator list while adding #16060
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… list while adding zend_array_dup_ht_iterators() loops over the hash table iterators and can call zend_hash_iterator_add(). zend_hash_iterator_add() can resize the array causing a crash in zend_array_dup_ht_iterators(). We solve this by refetching the iter pointer after an add happened.
nielsdos
commented
Sep 25, 2024
Zend/zend_hash.c
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| while (iter != end) { | ||
| if (iter->ht == source) { | ||
| size_t iter_index = iter - EG(ht_iterators); |
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Alternative idea is to use indices in the while loop, but then we have to fetch EG(ht_iterators) always in the loop body which seemed more expensive.
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I think indices are going to be better.
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Ok I have pushed a commit to do that.
dstogov
approved these changes
Sep 25, 2024
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zend_array_dup_ht_iterators() loops over the hash table iterators and can call zend_hash_iterator_add(). zend_hash_iterator_add() can resize the array causing a crash in zend_array_dup_ht_iterators().
We solve this by refetching the iter pointer after an add happened.