mmap base address must be computed wrt stack top address, using TASK_SIZE is wrong since STACK_TOP and TASK_SIZE are not equivalent. Signed-off-by: Alexandre Ghiti <alex@xxxxxxxx> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx> Acked-by: Paul Burton <paul.burton@xxxxxxxx> --- arch/mips/mm/mmap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c index 3ff82c6f7e24..ffbe69f3a7d9 100644 --- a/arch/mips/mm/mmap.c +++ b/arch/mips/mm/mmap.c @@ -22,7 +22,7 @@ EXPORT_SYMBOL(shm_align_mask); /* gap between mmap and stack */ #define MIN_GAP (128*1024*1024UL) -#define MAX_GAP ((TASK_SIZE)/6*5) +#define MAX_GAP ((STACK_TOP)/6*5) #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) static int mmap_is_legacy(struct rlimit *rlim_stack) @@ -54,7 +54,7 @@ static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack) else if (gap > MAX_GAP) gap = MAX_GAP; - return PAGE_ALIGN(TASK_SIZE - gap - rnd); + return PAGE_ALIGN(STACK_TOP - gap - rnd); } #define COLOUR_ALIGN(addr, pgoff) \ -- 2.20.1
