diff options
| author | David Rowley <drowley@postgresql.org> | 2025-10-21 20:46:14 +1300 |
|---|---|---|
| committer | David Rowley <drowley@postgresql.org> | 2025-10-21 20:46:14 +1300 |
| commit | 9fd29d7ff476f3f1c1a22d6d6f730e813eddd960 (patch) | |
| tree | a0ecbe54d7e33f691c677fc1ef594d59b5759dab | |
| parent | e4e496e88c9a0940abe1ade44337577b26f032a0 (diff) | |
Fix BRIN 32-bit counter wrap issue with huge tables
A BlockNumber (32-bit) might not be large enough to add bo_pagesPerRange
to when the table contains close to 2^32 pages. At worst, this could
result in a cancellable infinite loop during the BRIN index scan with
power-of-2 pagesPerRange, and slow (inefficient) BRIN index scans and
scanning of unneeded heap blocks for non power-of-2 pagesPerRange.
Backpatch to all supported versions.
Author: sunil s <sunilfeb26@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAOG6S4-tGksTQhVzJM19NzLYAHusXsK2HmADPZzGQcfZABsvpA@mail.gmail.com
Backpatch-through: 13
| -rw-r--r-- | src/backend/access/brin/brin.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/src/backend/access/brin/brin.c b/src/backend/access/brin/brin.c index 7ff7467e462..f37faf3562b 100644 --- a/src/backend/access/brin/brin.c +++ b/src/backend/access/brin/brin.c @@ -573,7 +573,6 @@ bringetbitmap(IndexScanDesc scan, TIDBitmap *tbm) Relation heapRel; BrinOpaque *opaque; BlockNumber nblocks; - BlockNumber heapBlk; int64 totalpages = 0; FmgrInfo *consistentFn; MemoryContext oldcxt; @@ -735,9 +734,10 @@ bringetbitmap(IndexScanDesc scan, TIDBitmap *tbm) /* * Now scan the revmap. We start by querying for heap page 0, * incrementing by the number of pages per range; this gives us a full - * view of the table. + * view of the table. We make use of uint64 for heapBlk as a BlockNumber + * could wrap for tables with close to 2^32 pages. */ - for (heapBlk = 0; heapBlk < nblocks; heapBlk += opaque->bo_pagesPerRange) + for (uint64 heapBlk = 0; heapBlk < nblocks; heapBlk += opaque->bo_pagesPerRange) { bool addrange; bool gottuple = false; @@ -749,7 +749,7 @@ bringetbitmap(IndexScanDesc scan, TIDBitmap *tbm) MemoryContextReset(perRangeCxt); - tup = brinGetTupleForHeapBlock(opaque->bo_rmAccess, heapBlk, &buf, + tup = brinGetTupleForHeapBlock(opaque->bo_rmAccess, (BlockNumber ) heapBlk, &buf, &off, &size, BUFFER_LOCK_SHARE); if (tup) { @@ -924,7 +924,7 @@ bringetbitmap(IndexScanDesc scan, TIDBitmap *tbm) /* add the pages in the range to the output bitmap, if needed */ if (addrange) { - BlockNumber pageno; + uint64 pageno; for (pageno = heapBlk; pageno <= Min(nblocks, heapBlk + opaque->bo_pagesPerRange) - 1; |