CVE-2026-72279

Summary

In the Linux kernel, the following vulnerability has been resolved:

KVM: arm64: nv: Respect read-only PFN when mapping L1 VNCR

KVM currently maps the L1 VNCR into the host stage-1 by relying entirely on the permissions of the guest stage-1. At the same time, it is entirely possible that the backing PFN is read-only (e.g. RO memslot), meaning that the L1 VNCR should use at most a read-only mapping.

Cache the writability of the PFN in the VNCR TLB and use it to constrain the resulting fixmap permissions. Promote VNCR permission faults to an SEA in the case where the guest attempts to write to a read-only endpoint. Conveniently, this also plugs a page leak found by Sashiko [*] resulting from the early return for a read-only PFN.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux2a359e072596fcb2e9e85017a865e3618a2fe5b5 < 5c50db5bcbb9073cb2fd97be51b962de92f429e9affected
LinuxLinux2a359e072596fcb2e9e85017a865e3618a2fe5b5 < d35defbdfcb15296ebe28968ad7452c1a8c11ceaaffected
LinuxLinux2a359e072596fcb2e9e85017a865e3618a2fe5b5 < 2684e02bac41c5220f6c1ab2bdcc957b71812977affected
LinuxLinux6.16affected
LinuxLinux0 < 6.16unaffected
LinuxLinux6.18.40 <= 6.18.*unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References