From 1a8f45464c1ef81dc8c2c16c8fbba2e696762962 Mon Sep 17 00:00:00 2001 From: Igor Nikonov Date: Tue, 13 Aug 2024 21:05:29 +0000 Subject: [PATCH] Fix min_marks_to_read overflow --- src/Storages/MergeTree/MergeTreeIndexGranularity.cpp | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/src/Storages/MergeTree/MergeTreeIndexGranularity.cpp b/src/Storages/MergeTree/MergeTreeIndexGranularity.cpp index 2a45ab1d927..2f9a4a47b11 100644 --- a/src/Storages/MergeTree/MergeTreeIndexGranularity.cpp +++ b/src/Storages/MergeTree/MergeTreeIndexGranularity.cpp @@ -103,8 +103,16 @@ size_t MergeTreeIndexGranularity::countMarksForRows(size_t from_mark, size_t num /// This is a heuristic to respect min_marks_to_read which is ignored by MergeTreeReadPool in case of remote disk. /// See comment in IMergeTreeSelectAlgorithm. - if (min_marks_to_read && from_mark + 2 * min_marks_to_read <= to_mark) - to_mark = from_mark + min_marks_to_read; + if (min_marks_to_read) + { + // check that ... + bool overflow = ((1ULL << 63) & min_marks_to_read); // further multiplication by 2 will not overflow + if (!overflow) + overflow = (std::numeric_limits::max() - from_mark) < 2 * min_marks_to_read; // further addition will not overflow + + if (!overflow && from_mark + 2 * min_marks_to_read <= to_mark) + to_mark = from_mark + min_marks_to_read; + } return getRowsCountInRange(from_mark, std::max(1UL, to_mark)) - offset_in_rows; }