diff options
| author |   Borislav Petkov <bp@suse.de> | 2015-04-01 12:49:52 +0200 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2015-04-03 15:26:15 +0200 |
| commit | 78cac48c0434c82e860fade3cd0420a7a4adbb08 (patch) | |
| tree | 76e1afefb1a0f9baad05487738de9f1b4a126aa7 /arch/x86/include/asm | |
| parent | x86/asm/entry: Drop now unused ENABLE_INTERRUPTS_SYSEXIT32 (diff) | |
| download | linux-dev-78cac48c0434c82e860fade3cd0420a7a4adbb08.tar.xz linux-dev-78cac48c0434c82e860fade3cd0420a7a4adbb08.zip | |
x86/mm/KASLR: Propagate KASLR status to kernel proper
Commit:
e2b32e678513 ("x86, kaslr: randomize module base load address")
made module base address randomization unconditional and didn't regard
disabled KKASLR due to CONFIG_HIBERNATION and command line option
"nokaslr". For more info see (now reverted) commit:
f47233c2d34f ("x86/mm/ASLR: Propagate base load address calculation")
In order to propagate KASLR status to kernel proper, we need a single bit
in boot_params.hdr.loadflags and we've chosen bit 1 thus leaving the
top-down allocated bits for bits supposed to be used by the bootloader.
Originally-From: Jiri Kosina <jkosina@suse.cz>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include/asm')
| -rw-r--r-- | arch/x86/include/asm/setup.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h index ff4e7b236e21..f69e06b283fb 100644 --- a/arch/x86/include/asm/setup.h +++ b/arch/x86/include/asm/setup.h @@ -66,6 +66,11 @@ static inline void x86_ce4100_early_setup(void) { } */ extern struct boot_params boot_params; +static inline bool kaslr_enabled(void) +{ + return !!(boot_params.hdr.loadflags & KASLR_FLAG); +} + /* * Do NOT EVER look at the BIOS memory size location. * It does not work on many machines. |