Commit-ID: 0f8ede1b8c4cb845c53072d7e49d71ca24a61ced Gitweb: http://git.kernel.org/tip/0f8ede1b8c4cb845c53072d7e49d71ca24a61ced Author: Kees Cook <[email protected]> AuthorDate: Wed, 20 Apr 2016 13:55:46 -0700 Committer: Ingo Molnar <[email protected]> CommitDate: Fri, 22 Apr 2016 10:00:51 +0200
x86/KASLR: Warn when KASLR is disabled If KASLR is built in but not available at run-time (either due to the current conflict with hibernation, command-line request, or e820 parsing failures), announce the state explicitly. To support this, a new "warn" function is created, based on the existing "error" function. Suggested-by: Ingo Molnar <[email protected]> Signed-off-by: Kees Cook <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Baoquan He <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: H.J. Lu <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Yinghai Lu <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/boot/compressed/kaslr.c | 6 +++--- arch/x86/boot/compressed/misc.c | 12 +++++++++--- arch/x86/boot/compressed/misc.h | 1 + 3 files changed, 13 insertions(+), 6 deletions(-) diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 3ad71a0..8741a6d 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -314,12 +314,12 @@ unsigned char *choose_random_location(unsigned char *input, #ifdef CONFIG_HIBERNATION if (!cmdline_find_option_bool("kaslr")) { - debug_putstr("KASLR disabled by default...\n"); + warn("KASLR disabled: 'kaslr' not on cmdline (hibernation selected)."); goto out; } #else if (cmdline_find_option_bool("nokaslr")) { - debug_putstr("KASLR disabled by cmdline...\n"); + warn("KASLR disabled: 'nokaslr' on cmdline."); goto out; } #endif @@ -333,7 +333,7 @@ unsigned char *choose_random_location(unsigned char *input, /* Walk e820 and find a random address. */ random_addr = find_random_addr(choice, output_size); if (!random_addr) { - debug_putstr("KASLR could not find suitable E820 region...\n"); + warn("KASLR disabled: could not find suitable E820 region!"); goto out; } diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index eacc855..c57d785 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -166,11 +166,17 @@ void __puthex(unsigned long value) } } -static void error(char *x) +void warn(char *m) { error_putstr("\n\n"); - error_putstr(x); - error_putstr("\n\n -- System halted"); + error_putstr(m); + error_putstr("\n\n"); +} + +static void error(char *m) +{ + warn(m); + error_putstr(" -- System halted"); while (1) asm("hlt"); diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 9887e0d..e75f6cf 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -35,6 +35,7 @@ extern memptr free_mem_end_ptr; extern struct boot_params *boot_params; void __putstr(const char *s); void __puthex(unsigned long value); +void warn(char *m); #define error_putstr(__x) __putstr(__x) #define error_puthex(__x) __puthex(__x)
