riscv/mm: use physical alignment for vmemmap_start_pfn

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-80682
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-08-28 08:16:53 UTC
Updated2026-08-28 08:16:53 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: riscv/mm: use physical alignment for vmemmap_start_pfn RISC-V computes vmemmap_start_pfn by rounding phys_ram_base down to VMEMMAP_ADDR_ALIGN. That alignment must therefore be expressed in the physical-address domain. Commit 476849b0fba4 ("riscv/mm: align vmemmap to maximal folio size") attempted to account for the maximal folio alignment by feeding MAX_FOLIO_VMEMMAP_ALIGN directly into VMEMMAP_ADDR_ALIGN. However, MAX_FOLIO_VMEMMAP_ALIGN is measured in bytes of struct page storage, whereas VMEMMAP_ADDR_ALIGN is used to align a physical address. The mask-based compound_info encoding requires pfn_to_page(0) to be naturally aligned to MAX_FOLIO_VMEMMAP_ALIGN. Commit 9f94db4c7eaa ("mm/sparse: check memmap alignment for compound_info_has_mask()") added a check for that requirement and exposed the unit mismatch on systems such as QEMU virt, where the DRAM base is not aligned to MAX_FOLIO_NR_PAGES * PAGE_SIZE. Here is the log: [ 0.000000][ C0] ------------[ cut here ]------------ [ 0.000000][ C0] WARNING: mm/sparse.c:365 at sparse_init+0x58a/0x6fe, CPU#0: swapper/0 [ 0.000000][ C0] Modules linked in: [ 0.000000][ C0] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 7.2.0-rc3-g1d8304bdd65f #2 PREEMPT [ 0.000000][ C0] Hardware name: riscv-virtio,qemu (DT) [ 0.000000][ C0] epc : sparse_init+0x58a/0x6fe [ 0.000000][ C0] ra : sparse_init+0x58a/0x6fe [ 0.000000][ C0] epc : ffffffff86851c88 ra : ffffffff86851c88 sp : ffffffff88807a30 [ 0.000000][ C0] gp : ffffffff8a3bf240 tp : ffffffff88842080 t0 : ff600000ffab6000 [ 0.000000][ C0] t1 : 000000017fab6000 t2 : 65203a6573726363 s0 : ffffffff88807bc0 [ 0.000000][ C0] s1 : 000000000e000000 a0 : 0000000000000007 a1 : 0000000000000000 [ 0.000000][ C0] a2 : 0000000000000002 a3 : ffffffff86851c88 a4 : 0000000000000000 [ 0.000000][ C0] a5 : ffffffff88843080 a6 : 0000000000000003 a7 : 0000000000000000 [ 0.000000][ C0] s2 : ff60000000000000 s3 : 0040000000000000 s4 : 0004000000000000 [ 0.000000][ C0] s5 : ffffffff8a4d92e0 s6 : ff600000ffab55e0 s7 : ffffffff88384d00 [ 0.000000][ C0] s8 : 0000000000000003 s9 : ffffffff88384cc1 s10: ffffffff88384cc0 [ 0.000000][ C0] s11: ffffffff8a4daae0 t3 : ffffffff915e8b20 t4 : ffffffff915e8b20 [ 0.000000][ C0] t5 : ffffffff915e8b20 t6 : ffffffff915e8bc8 ssp : 0000000000000000 [ 0.000000][ C0] status: 0000000200000100 badaddr: ffffffff86851c88 cause: 0000000000000003 [ 0.000000][ C0] [<ffffffff86851c88>] sparse_init+0x58a/0x6fe [ 0.000000][ C0] [<ffffffff8683d396>] mm_core_init_early+0x116/0x1e30 [ 0.000000][ C0] [<ffffffff86801edc>] start_kernel+0xd2/0x848 Convert MAX_FOLIO_VMEMMAP_ALIGN to the equivalent physical alignment before using it in VMEMMAP_ADDR_ALIGN. This keeps the existing round_down() logic while making the resulting vmemmap base satisfy the mask-alignment requirement.

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected 476849b0fba4450f5adf22196bcff9c24c673bc4 11ad86830a78ea4e1942afc73c10e4ca8e69e03f git Not specified
CNA Linux Linux affected 476849b0fba4450f5adf22196bcff9c24c673bc4 45ebe4540817cb540a59e4dc04014ac5dddc9990 git Not specified
CNA Linux Linux affected 7.1 Not specified
CNA Linux Linux unaffected 7.1 semver Not specified
CNA Linux Linux unaffected 7.1.8 7.1.* semver Not specified
CNA Linux Linux unaffected 7.2 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/11ad86830a78ea4e1942afc73c10e4ca8e69e03f 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/45ebe4540817cb540a59e4dc04014ac5dddc9990 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report