Hello! On 08.08.2019 9:17, Alexandre Ghiti wrote:
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 <[email protected]> Signed-off-by: Alexandre Ghiti <[email protected]> Acked-by: Paul Burton <[email protected]> Reviewed-by: Kees Cook <[email protected]> Reviewed-by: Luis Chamberlain <[email protected]> --- 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
[...]
@@ -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);
Why not make these 'rnd &= SZ_* - 1', while at it anyways? [...] MBR, Sergei
