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| author | Daniel Gustafsson <dgustafsson@postgresql.org> | 2024-02-29 12:19:52 +0100 |
|---|---|---|
| committer | Daniel Gustafsson <dgustafsson@postgresql.org> | 2024-02-29 12:19:52 +0100 |
| commit | 217928ddb45a8a3b03fc1f9d3d97166f1d9a9d12 (patch) | |
| tree | d723bfae4ea11bea2d35f9916a834e9e813408fe | |
| parent | fe3b1b575e24748ddb9b3b67394fa10c279090ac (diff) | |
| download | postgresql-217928ddb45a8a3b03fc1f9d3d97166f1d9a9d12.tar.gz postgresql-217928ddb45a8a3b03fc1f9d3d97166f1d9a9d12.zip | |
Fix integer underflow in shared memory debugging
dsa_dump would print a large negative number instead of zero for
segment bin 0. Fix by explicitly checking for underflow and add
special case for bin 0. Backpatch to all supported versions.
Author: Ian Ilyasov <ianilyasov@outlook.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/GV1P251MB1004E0D09D117D3CECF9256ECD502@GV1P251MB1004.EURP251.PROD.OUTLOOK.COM
Backpatch-through: v12
| -rw-r--r-- | src/backend/utils/mmgr/dsa.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/src/backend/utils/mmgr/dsa.c b/src/backend/utils/mmgr/dsa.c index dddffcad913..1f2f825071d 100644 --- a/src/backend/utils/mmgr/dsa.c +++ b/src/backend/utils/mmgr/dsa.c @@ -1093,9 +1093,13 @@ dsa_dump(dsa_area *area) { dsa_segment_index segment_index; - fprintf(stderr, - " segment bin %zu (at least %d contiguous pages free):\n", - i, 1 << (i - 1)); + if (i == 0) + fprintf(stderr, + " segment bin %zu (no contiguous free pages):\n", i); + else + fprintf(stderr, + " segment bin %zu (at least %d contiguous pages free):\n", + i, 1 << (i - 1)); segment_index = area->control->segment_bins[i]; while (segment_index != DSA_SEGMENT_INDEX_NONE) { |