CVE-2022-49004 Information

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.

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Reference

https://git.kernel.org/stable/c/fa7a7d185ef380546b4b1fed6f84f31dbae8cec7 https://git.kernel.org/stable/c/96f479383d92944406d4b3f2bc03c2f640def9f1 https://git.kernel.org/stable/c/3f105a742725a1b78766a55169f1d827732e62b8

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

5.5