cbcvebase.
CVE-2021-47228
published 2024-05-21

CVE-2021-47228: In the Linux kernel, the following vulnerability has been resolved: x86/ioremap: Map EFI-reserved memory as encrypted for SEV Some drivers require memory that…

PriorityP422medium6.2CVSS 3.1
AVLACLPRNUINSUCNINAH
EPSS
0.24%
14.8th percentile
In the Linux kernel, the following vulnerability has been resolved: x86/ioremap: Map EFI-reserved memory as encrypted for SEV Some drivers require memory that is marked as EFI boot services data. In order for this memory to not be re-used by the kernel after ExitBootServices(), efi_mem_reserve() is used to preserve it by inserting a new EFI memory descriptor and marking it with the EFI_MEMORY_RUNTIME attribute. Under SEV, memory marked with the EFI_MEMORY_RUNTIME attribute needs to be mapped encrypted by Linux, otherwise the kernel might crash at boot like below: EFI Variables Facility v0.08 2004-May-17 general protection fault, probably for non-canonical address 0x3597688770a868b2: 0000 [#1] SMP NOPTI CPU: 13 PID: 1 Comm: swapper/0 Not tainted 5.12.4-2-default #1 openSUSE Tumbleweed Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:efi_mokvar_entry_next [...] Call Trace: efi_mokvar_sysfs_init ? efi_mokvar_table_init do_one_initcall ? __kmalloc kernel_init_freeable ? rest_init kernel_init ret_from_fork Expand the __ioremap_check_other() function to additionally check for this other type of boot data reserved at runtime and indicate that it should be mapped encrypted for an SEV guest. [ bp: Massage commit message. ]

Affected

12 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.46-1 (bookworm)linux 5.10.46-1 (bookworm)
linuxlinux
linuxlinux>= 58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 < 208bb686e7fa7fff16e8fa78ff0db34aa9acdbd7208bb686e7fa7fff16e8fa78ff0db34aa9acdbd7
linuxlinux>= 58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 < b7a05aba39f733ec337c5b952e112dd2dc4fc404b7a05aba39f733ec337c5b952e112dd2dc4fc404
linuxlinux>= 58c909022a5a56cd1d9e89c8c5461fd1f6a27bb5 < 8d651ee9c71bb12fc0c8eb2786b66cbe5aa3e43b8d651ee9c71bb12fc0c8eb2786b66cbe5aa3e43b
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 5.10 < 5.10.465.10.46
linuxlinux_kernel>= 5.11 < 5.12.135.12.13

CVSS provenance

nvdv3.16.2MEDIUMCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv6.2MEDIUM
vendor_debian6.2MEDIUM
vendor_redhat6.2MEDIUM
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