{"id":"CVE-2021-47228","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/ioremap: Map EFI-reserved memory as encrypted for SEV\n\nSome drivers require memory that is marked as EFI boot services\ndata. In order for this memory to not be re-used by the kernel\nafter ExitBootServices(), efi_mem_reserve() is used to preserve it\nby inserting a new EFI memory descriptor and marking it with the\nEFI_MEMORY_RUNTIME attribute.\n\nUnder SEV, memory marked with the EFI_MEMORY_RUNTIME attribute needs to\nbe mapped encrypted by Linux, otherwise the kernel might crash at boot\nlike below:\n\n  EFI Variables Facility v0.08 2004-May-17\n  general protection fault, probably for non-canonical address 0x3597688770a868b2: 0000 [#1] SMP NOPTI\n  CPU: 13 PID: 1 Comm: swapper/0 Not tainted 5.12.4-2-default #1 openSUSE Tumbleweed\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:efi_mokvar_entry_next\n  [...]\n  Call Trace:\n   efi_mokvar_sysfs_init\n   ? efi_mokvar_table_init\n   do_one_initcall\n   ? __kmalloc\n   kernel_init_freeable\n   ? rest_init\n   kernel_init\n   ret_from_fork\n\nExpand the __ioremap_check_other() function to additionally check for\nthis other type of boot data reserved at runtime and indicate that it\nshould be mapped encrypted for an SEV guest.\n\n [ bp: Massage commit message. ]","modified":"2026-03-15T22:43:08.605456Z","published":"2024-05-21T15:15:12.250Z","related":["SUSE-SU-2024:2010-1","SUSE-SU-2024:2185-1"],"references":[{"type":"FIX","url":"https://git.kernel.org/stable/c/8d651ee9c71bb12fc0c8eb2786b66cbe5aa3e43b"},{"type":"FIX","url":"https://git.kernel.org/stable/c/b7a05aba39f733ec337c5b952e112dd2dc4fc404"},{"type":"FIX","url":"https://git.kernel.org/stable/c/208bb686e7fa7fff16e8fa78ff0db34aa9acdbd7"}],"affected":[{"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47228.json","unresolved_ranges":[{"events":[{"introduced":"5.10"},{"fixed":"5.10.46"}]},{"events":[{"introduced":"5.11"},{"fixed":"5.12.13"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc1"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc2"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc3"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc4"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc5"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc6"}]}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}