CFBinaryHeap: fix out-of-bounds accesses in copy and remove#48
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DTW-Thalion wants to merge 1 commit into
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CFBinaryHeap: fix out-of-bounds accesses in copy and remove#48DTW-Thalion wants to merge 1 commit into
DTW-Thalion wants to merge 1 commit into
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Two out-of-bounds heap accesses, both reachable from the public API and
confirmed with AddressSanitizer:
* CFBinaryHeapCreateCopy() created the new heap with the requested
capacity and then memcpy'd _count values into it. When the requested
capacity was smaller than the source count (e.g. 0) the destination
was only DEFAULT_HEAP_CAPACITY (15) slots, so copying a larger heap
overran it (heap-buffer-overflow WRITE in CFBinaryHeapCreateCopy).
* CFBinaryHeapRemoveMinimumValue() unconditionally read _values[0] and
_values[_count - 1] and decremented _count. On an empty heap that
read _values[-1] (heap-buffer-overflow READ) and left _count at -1.
Enlarge the copy's capacity to at least the source count, and make
removing from an empty heap a no-op. Adds regression tests.
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Two out-of-bounds heap accesses, both reachable from the public API and
confirmed with AddressSanitizer:
CFBinaryHeapCreateCopy() created the new heap with the requested
capacity and then memcpy'd _count values into it. When the requested
capacity was smaller than the source count (e.g. 0) the destination
was only DEFAULT_HEAP_CAPACITY (15) slots, so copying a larger heap
overran it (heap-buffer-overflow WRITE in CFBinaryHeapCreateCopy).
CFBinaryHeapRemoveMinimumValue() unconditionally read _values[0] and
_values[_count - 1] and decremented _count. On an empty heap that
read _values[-1] (heap-buffer-overflow READ) and left _count at -1.
Enlarge the copy's capacity to at least the source count, and make
removing from an empty heap a no-op. Adds regression tests.