Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — RDMA/core: Fix ib block iterator counter overflow
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U N N H 5.5 .0019 8.8 —
AFFECTED
Product Versions Fixed
Linux a808273a495c657e33281b181fd7fcc2bb28f662 – —
Linux 5.2 – 5.4.231
TIMELINE
Mar 27 Reserved by Linux
Mar 27 Published (CNA: Linux)
Aug 4 RESCORED — CVE-2023-53026 (Linux). CVSS 7.8 → 5.5 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
RDMA/core: Fix ib block iterator counter overflow
When registering a new DMA MR after selecting the best aligned page size
for it, we iterate over the given sglist to split each entry to smaller,
aligned to the selected page size, DMA blocks.
In given circumstances where the sg entry and page size fit certain
sizes and the sg entry is not aligned to the selected page size, the
total size of the aligned pages we need to cover the sg entry is >= 4GB.
Under this circumstances, while iterating page aligned blocks, the
counter responsible for counting how much we advanced from the start of
the sg entry is overflowed because its type is u32 and we pass 4GB in
size. This can lead to an infinite loop inside the iterator function
because the overflow prevents the counter to be larger
than the size of the sg entry.
Fix the presented problem by changing the advancement condition to
eliminate overflow.
Backtrace:
[ 192.374329] efa_reg_user_mr_dmabuf
[ 192.376783] efa_register_mr
[ 192.382579] pgsz_bitmap 0xfffff000 rounddown 0x80000000
[ 192.386423] pg_sz [0x80000000] umem_length[0xc0000000]
[ 192.392657] start 0x0 length 0xc0000000 params.page_shift 31 params.page_num 3
[ 192.399559] hp_cnt[3], pages_in_hp[524288]
[ 192.403690] umem->sgt_append.sgt.nents[1]
[ 192.407905] number entries: [1], pg_bit: [31]
[ 192.411397] biter->__sg_nents [1] biter->__sg [0000000008b0c5d8]
[ 192.415601] biter->__sg_advance [665837568] sg_dma_len[3221225472]
[ 192.419823] biter->__sg_nents [1] biter->__sg [0000000008b0c5d8]
[ 192.423976] biter->__sg_advance [2813321216] sg_dma_len[3221225472]
[ 192.428243] biter->__sg_nents [1] biter->__sg [0000000008b0c5d8]
[ 192.432397] biter->__sg_advance [665837568] sg_dma_len[3221225472]
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| March 27, 2025 | Reserved | Reserved by Linux |
| March 27, 2025 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2023-53026 (Linux). CVSS 7.8 → 5.5 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | a808273a495c657e33281b181fd7fcc2bb28f662 | — |
| Linux | Linux | — | 5.2 | 5.4.231 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2023-53026 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.