CVE-2026-98638 PUBLISHED

KVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()

Assigner: Linux
Reserved: 25.09.2026 Published: 18.10.2026 Updated: 18.10.2026

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

KVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()

pkvm_vcpu_init_sve() clamps only the upper bound of the host-provided sve_max_vl, so an invalid vector length reaches sve_state_size_from_vl() and the WARN_ON() there, which is fatal at EL2. The existing !sve_state_size test rejects such a length, but only after the macro has run.

Check sve_vl_valid() before deriving the state size. A valid length cannot yield a zero size, so the !sve_state_size test goes with it.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 5db1bef933427aa467ad89c7b695a84a6b4afe16 to faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc (excl.)
  • affected from 5db1bef933427aa467ad89c7b695a84a6b4afe16 to bae3e4493046de4fefa15f809d9b8dc114e84a3d (excl.)
  • affected from 5db1bef933427aa467ad89c7b695a84a6b4afe16 to 2a2eb10795a1e495aebc7f829ccecb72c05b4fd9 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 6.16 is affected
  • unaffected from 0 to 6.16 (excl.)
  • unaffected from 6.18.55 to 6.18.* (incl.)
  • unaffected from 7.2.9 to 7.2.* (incl.)
  • unaffected from 7.3-rc5 to * (incl.)

References