linux/arch/x86/boot
Michael Roth 4b1c742407 x86/boot: Don't propagate uninitialized boot_params->cc_blob_address
In some cases, bootloaders will leave boot_params->cc_blob_address
uninitialized rather than zeroing it out. This field is only meant to be
set by the boot/compressed kernel in order to pass information to the
uncompressed kernel when SEV-SNP support is enabled.

Therefore, there are no cases where the bootloader-provided values
should be treated as anything other than garbage. Otherwise, the
uncompressed kernel may attempt to access this bogus address, leading to
a crash during early boot.

Normally, sanitize_boot_params() would be used to clear out such fields
but that happens too late: sev_enable() may have already initialized
it to a valid value that should not be zeroed out. Instead, have
sev_enable() zero it out unconditionally beforehand.

Also ensure this happens for !CONFIG_AMD_MEM_ENCRYPT as well by also
including this handling in the sev_enable() stub function.

  [ bp: Massage commit message and comments. ]

Fixes: b190a043c4 ("x86/sev: Add SEV-SNP feature detection/setup")
Reported-by: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
Reported-by: watnuss@gmx.de
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216387
Link: https://lore.kernel.org/r/20220823160734.89036-1-michael.roth@amd.com
2022-08-24 09:03:04 +02:00
..
compressed x86/boot: Don't propagate uninitialized boot_params->cc_blob_address 2022-08-24 09:03:04 +02:00
tools x86/build: Declutter the build output 2020-08-20 08:17:40 +02:00
.gitignore x86/boot: Modernize genimage script; hdimage+EFI support 2021-05-10 12:27:50 +02:00
a20.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
apm.c x86/boot: Fix comment spelling 2020-03-17 20:52:52 +01:00
bioscall.S treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 83 2019-05-24 17:37:52 +02:00
bitops.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
boot.h - Add a "make x86_debug.config" target which enables a bunch of useful 2022-05-23 18:15:44 -07:00
cmdline.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
copy.S x86/asm: Do not annotate functions with GLOBAL 2019-10-18 11:25:58 +02:00
cpu.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
cpucheck.c x86/boot: Use MSR read/write helpers instead of inline assembly 2022-04-06 13:02:13 +02:00
cpuflags.c x86/tdx: Detect TDX at early kernel decompression time 2022-04-07 08:27:51 -07:00
cpuflags.h x86/tdx: Detect TDX at early kernel decompression time 2022-04-07 08:27:51 -07:00
ctype.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
early_serial_console.c x86: Clean up 'sizeof x' => 'sizeof(x)' 2018-10-29 07:13:28 +01:00
edd.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
genimage.sh x86/boot: Fix make hdimage with older versions of mtools 2021-09-29 11:06:47 +02:00
header.S efi: x86: Fix config name for setting the NX-compatibility flag in the PE header 2022-06-01 14:07:48 +02:00
install.sh kbuild: factor out the common installation code into scripts/install.sh 2022-05-11 21:45:53 +09:00
io.h x86/boot: Port I/O: Allow to hook up alternative helpers 2022-04-07 08:27:52 -07:00
main.c - Add a "make x86_debug.config" target which enables a bunch of useful 2022-05-23 18:15:44 -07:00
Makefile x86: link vdso and boot with -z noexecstack --no-warn-rwx-segments 2022-08-10 18:30:09 -07:00
memory.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
mkcpustr.c x86/cpu: Print VMX flags in /proc/cpuinfo using VMX_FEATURES_* 2020-01-13 18:36:02 +01:00
msr.h x86/boot: Introduce helpers for MSR reads/writes 2022-04-06 12:59:17 +02:00
mtools.conf.in x86/boot: Fix make hdimage with older versions of mtools 2021-09-29 11:06:47 +02:00
pm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
pmjump.S x86/asm: Do not annotate functions with GLOBAL 2019-10-18 11:25:58 +02:00
printf.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
regs.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 83 2019-05-24 17:37:52 +02:00
setup.ld x86/boot: Add .text.* to setup.ld 2020-08-14 12:52:35 +02:00
string.c x86/boot: Add kstrtoul() from lib/ 2020-05-04 15:19:07 +02:00
string.h x86/boot/string: Add missing function prototypes 2021-12-10 19:49:06 +01:00
tty.c treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
version.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
vesa.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 48 2019-05-24 17:27:13 +02:00
video-bios.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
video-mode.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
video-vesa.c sysfb: Enable boot time VESA graphic mode selection 2022-03-04 20:55:33 +01:00
video-vga.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
video.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 2019-06-19 17:09:53 +02:00
video.h treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00