CVE-2022-49004: riscv: Sync efi page table's kernel mappings before switching

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-10-21 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: riscv: Sync efi page table's kernel mappings before switching The EFI page table is initially created as a copy of the kernel page table. With VMAP_STACK enabled, kernel stacks are allocated in the vmalloc area: if the stack is allocated in a new PGD (one that was not present at the moment of the efi page table creation or not synced in a previous vmalloc fault), the kernel will take a trap when switching to the efi page table when the vmalloc kernel stack is accessed, resulting in a kernel panic. Fix that by updating the efi kernel mappings before switching to the efi page table.

Affected products

Linux kernel: from 5.10 before 5.15.82; from 5.16 before 6.0.12; 6.1-rc1, 6.1-rc2, 6.1-rc3, 6.1-rc4, 6.1-rc5, 6.1-rc6 (+1) — fixed in 5.15.82, 6.0.12

How to fix

Upgrade to a fixed version: Linux kernel 5.15.82, 6.0.12. Check the vendor advisory for mitigations.

References

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