diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/arm64/kernel/pi/kaslr_early.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/arch/arm64/kernel/pi/kaslr_early.c b/arch/arm64/kernel/pi/kaslr_early.c index 17bff6e399e4..b9e0bb4bc6a9 100644 --- a/arch/arm64/kernel/pi/kaslr_early.c +++ b/arch/arm64/kernel/pi/kaslr_early.c @@ -14,6 +14,7 @@ #include <asm/archrandom.h> #include <asm/memory.h> +#include <asm/pgtable.h> /* taken from lib/string.c */ static char *__strstr(const char *s1, const char *s2) @@ -87,7 +88,7 @@ static u64 get_kaslr_seed(void *fdt) asmlinkage u64 kaslr_early_init(void *fdt) { - u64 seed; + u64 seed, range; if (is_kaslr_disabled_cmdline(fdt)) return 0; @@ -102,9 +103,9 @@ asmlinkage u64 kaslr_early_init(void *fdt) /* * OK, so we are proceeding with KASLR enabled. Calculate a suitable * kernel image offset from the seed. Let's place the kernel in the - * middle half of the VMALLOC area (VA_BITS_MIN - 2), and stay clear of - * the lower and upper quarters to avoid colliding with other - * allocations. + * 'middle' half of the VMALLOC area, and stay clear of the lower and + * upper quarters to avoid colliding with other allocations. */ - return BIT(VA_BITS_MIN - 3) + (seed & GENMASK(VA_BITS_MIN - 3, 0)); + range = (VMALLOC_END - KIMAGE_VADDR) / 2; + return range / 2 + (((__uint128_t)range * seed) >> 64); } |