diff options
| author | Jiri Kosina <jkosina@suse.cz> | 2015-02-13 16:04:55 +0100 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2015-02-19 11:38:54 +0100 |
| commit | f47233c2d34f243ecdaac179c3408a39ff9216a7 (patch) | |
| tree | b42d4847dd27acbea3526134adfc3f7b5780c5cd /arch/x86/boot/compressed/misc.h | |
| parent | bfa76d49576599a4b9f9b7a71f23d73d6dcff735 (diff) | |
x86/mm/ASLR: Propagate base load address calculation
Commit:
e2b32e678513 ("x86, kaslr: randomize module base load address")
makes the base address for module to be unconditionally randomized in
case when CONFIG_RANDOMIZE_BASE is defined and "nokaslr" option isn't
present on the commandline.
This is not consistent with how choose_kernel_location() decides whether
it will randomize kernel load base.
Namely, CONFIG_HIBERNATION disables kASLR (unless "kaslr" option is
explicitly specified on kernel commandline), which makes the state space
larger than what module loader is looking at. IOW CONFIG_HIBERNATION &&
CONFIG_RANDOMIZE_BASE is a valid config option, kASLR wouldn't be applied
by default in that case, but module loader is not aware of that.
Instead of fixing the logic in module.c, this patch takes more generic
aproach. It introduces a new bootparam setup data_type SETUP_KASLR and
uses that to pass the information whether kaslr has been applied during
kernel decompression, and sets a global 'kaslr_enabled' variable
accordingly, so that any kernel code (module loading, livepatching, ...)
can make decisions based on its value.
x86 module loader is converted to make use of this flag.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Link: https://lkml.kernel.org/r/alpine.LNX.2.00.1502101411280.10719@pobox.suse.cz
[ Always dump correct kaslr status when panicking ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Diffstat (limited to 'arch/x86/boot/compressed/misc.h')
| -rw-r--r-- | arch/x86/boot/compressed/misc.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 24e3e569a13c..6d6730743024 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -56,7 +56,8 @@ int cmdline_find_option_bool(const char *option); #if CONFIG_RANDOMIZE_BASE /* aslr.c */ -unsigned char *choose_kernel_location(unsigned char *input, +unsigned char *choose_kernel_location(struct boot_params *params, + unsigned char *input, unsigned long input_size, unsigned char *output, unsigned long output_size); @@ -64,7 +65,8 @@ unsigned char *choose_kernel_location(unsigned char *input, bool has_cpuflag(int flag); #else static inline -unsigned char *choose_kernel_location(unsigned char *input, +unsigned char *choose_kernel_location(struct boot_params *params, + unsigned char *input, unsigned long input_size, unsigned char *output, unsigned long output_size) |