diff options
Diffstat (limited to 'arch/x86/boot/compressed/kaslr.c')
| -rw-r--r-- | arch/x86/boot/compressed/kaslr.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 36e28112523a..749c9e00c674 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -492,7 +492,7 @@ void choose_random_location(unsigned long input, unsigned long output_size, unsigned long *virt_addr) { - unsigned long random_addr; + unsigned long random_addr, min_addr; /* By default, keep output position unchanged. */ *virt_addr = *output; @@ -510,8 +510,15 @@ void choose_random_location(unsigned long input, /* Record the various known unsafe memory ranges. */ mem_avoid_init(input, input_size, *output); + /* + * Low end of the randomization range should be the + * smaller of 512M or the initial kernel image + * location: + */ + min_addr = min(*output, 512UL << 20); + /* Walk e820 and find a random address. */ - random_addr = find_random_phys_addr(*output, output_size); + random_addr = find_random_phys_addr(min_addr, output_size); if (!random_addr) { warn("KASLR disabled: could not find suitable E820 region!"); } else { |