6.1-stable review patch. If anyone has any objections, please let me know.
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From: Ard Biesheuvel ardb+git@google.com
From: Yuntao Wang ytcoode@gmail.com
[ Commit 01638431c465741e071ab34acf3bef3c2570f878 upstream ]
When KASLR is enabled, the KASLR_FLAG bit in boot_params->hdr.loadflags should be set to 1 to propagate KASLR status from compressed kernel to kernel, just as the choose_random_location() function does.
Currently, when the kernel is booted via the EFI stub, the KASLR_FLAG bit in boot_params->hdr.loadflags is not set, even though it should be. This causes some functions, such as kernel_randomize_memory(), not to execute as expected. Fix it.
Fixes: a1b87d54f4e4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot") Signed-off-by: Yuntao Wang ytcoode@gmail.com [ardb: drop 'else' branch clearing KASLR_FLAG] Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/firmware/efi/libstub/x86-stub.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/firmware/efi/libstub/x86-stub.c +++ b/drivers/firmware/efi/libstub/x86-stub.c @@ -781,6 +781,8 @@ static efi_status_t efi_decompress_kerne efi_debug("AMI firmware v2.0 or older detected - disabling physical KASLR\n"); seed[0] = 0; } + + boot_params_ptr->hdr.loadflags |= KASLR_FLAG; }
status = efi_random_alloc(alloc_size, CONFIG_PHYSICAL_ALIGN, &addr,