diff options
| -rw-r--r-- | arch/x86/include/asm/elf.h | 2 | ||||
| -rw-r--r-- | arch/x86/mm/mmap.c | 17 |
2 files changed, 17 insertions, 2 deletions
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index 83c1bc8d2e8a..456a304b8172 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -299,6 +299,8 @@ do { \ #ifdef CONFIG_X86_32 +#define STACK_RND_MASK (0x7ff) + #define VDSO_HIGH_BASE (__fix_to_virt(FIX_VDSO)) #define ARCH_DLINFO ARCH_DLINFO_IA32(vdso_enabled) diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c index 165829600566..c8191defc38a 100644 --- a/arch/x86/mm/mmap.c +++ b/arch/x86/mm/mmap.c @@ -29,13 +29,26 @@ #include <linux/random.h> #include <linux/limits.h> #include <linux/sched.h> +#include <asm/elf.h> + +static unsigned int stack_maxrandom_size(void) +{ + unsigned int max = 0; + if ((current->flags & PF_RANDOMIZE) && + !(current->personality & ADDR_NO_RANDOMIZE)) { + max = ((-1U) & STACK_RND_MASK) << PAGE_SHIFT; + } + + return max; +} + /* * Top of mmap area (just below the process stack). * - * Leave an at least ~128 MB hole. + * Leave an at least ~128 MB hole with possible stack randomization. */ -#define MIN_GAP (128*1024*1024) +#define MIN_GAP (128*1024*1024UL + stack_maxrandom_size()) #define MAX_GAP (TASK_SIZE/6*5) /* |