summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
Diffstat (limited to 'arch')
-rw-r--r--arch/s390/include/asm/elf.h3
-rw-r--r--arch/s390/kernel/process.c18
2 files changed, 21 insertions, 0 deletions
diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h
index 9dbd3e7a3bc3..457fb7c16236 100644
--- a/arch/s390/include/asm/elf.h
+++ b/arch/s390/include/asm/elf.h
@@ -220,4 +220,7 @@ struct linux_binprm;
#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
int arch_setup_additional_pages(struct linux_binprm *, int);
+extern unsigned long arch_randomize_brk(struct mm_struct *mm);
+#define arch_randomize_brk arch_randomize_brk
+
#endif
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 38ff69e562c8..26d48fe72999 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -341,3 +341,21 @@ unsigned long arch_align_stack(unsigned long sp)
sp -= get_random_int() & ~PAGE_MASK;
return sp & ~0xf;
}
+
+static inline unsigned long brk_rnd(void)
+{
+ /* 8MB for 32bit, 1GB for 64bit */
+ if (is_32bit_task())
+ return (get_random_int() & 0x7ffUL) << PAGE_SHIFT;
+ else
+ return (get_random_int() & 0x3ffffUL) << PAGE_SHIFT;
+}
+
+unsigned long arch_randomize_brk(struct mm_struct *mm)
+{
+ unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
+
+ if (ret < mm->brk)
+ return mm->brk;
+ return ret;
+}