MDEV-38004 Double free on re-execution of prepared aggregate function - #5635
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KhaledR57 wants to merge 1 commit into
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MDEV-38004 Double free on re-execution of prepared aggregate function#5635KhaledR57 wants to merge 1 commit into
KhaledR57 wants to merge 1 commit into
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Between two executions of a prepared statement, Item_sp::cleanup() freed the stored function's memory root but left the arena's free list pointing into it. That list is filled when the function call returns and the active arena is restored. On the next execution Item_sum_sp::clear() walked the stale list and destroyed already freed items. Free the items before freeing the memory they live in, the order Item_sum_sp::clear() already uses.
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Between two executions of a prepared statement,
Item_sp::cleanup()freed the stored function's memory root but left the arena's free list pointing into it. That list is filled when the function call returns and the active arena is restored.On the next execution
Item_sum_sp::clear()walked the stale list and destroyed already freed items.Free the items before freeing the memory they live in, the order
Item_sum_sp::clear()already uses.