diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/utils/sort/tuplesort.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c index 64ef6e5032c..4dd5407f741 100644 --- a/src/backend/utils/sort/tuplesort.c +++ b/src/backend/utils/sort/tuplesort.c @@ -3800,7 +3800,7 @@ tuplesort_heap_siftup(Tuplesortstate *state, bool checkIndex) { SortTuple *memtuples = state->memtuples; SortTuple *tuple; - int i, + unsigned int i, n; Assert(!checkIndex || state->currentRun == RUN_FIRST); @@ -3809,12 +3809,17 @@ tuplesort_heap_siftup(Tuplesortstate *state, bool checkIndex) CHECK_FOR_INTERRUPTS(); + /* + * state->memtupcount is "int", but we use "unsigned int" for i, j, n. + * This prevents overflow in the "2 * i + 1" calculation, since at the top + * of the loop we must have i < n <= INT_MAX <= UINT_MAX/2. + */ n = state->memtupcount; tuple = &memtuples[n]; /* tuple that must be reinserted */ i = 0; /* i is where the "hole" is */ for (;;) { - int j = 2 * i + 1; + unsigned int j = 2 * i + 1; if (j >= n) break; |