This commit simply bumps up to 32MB and 1GB the random offset of brk, compared to 8MB and 256MB, for 32bit and 64bit respectively. Suggested-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Alexandre Ghiti <alex@xxxxxxxx> Acked-by: Paul Burton <paul.burton@xxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> Reviewed-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> --- arch/mips/mm/mmap.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c index a7e84b2e71d7..ff6ab87e9c56 100644 --- a/arch/mips/mm/mmap.c +++ b/arch/mips/mm/mmap.c @@ -16,6 +16,7 @@ #include <linux/random.h> #include <linux/sched/signal.h> #include <linux/sched/mm.h> +#include <linux/sizes.h> unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */ EXPORT_SYMBOL(shm_align_mask); @@ -189,11 +190,11 @@ static inline unsigned long brk_rnd(void) unsigned long rnd = get_random_long(); rnd = rnd << PAGE_SHIFT; - /* 8MB for 32bit, 256MB for 64bit */ + /* 32MB for 32bit, 1GB for 64bit */ if (TASK_IS_32BIT_ADDR) - rnd = rnd & 0x7ffffful; + rnd = rnd & (SZ_32M - 1); else - rnd = rnd & 0xffffffful; + rnd = rnd & (SZ_1G - 1); return rnd; } -- 2.20.1
