[ARM] implement arch_randomize_brk()
For this feature to take effect, CONFIG_COMPAT_BRK must be turned
off. This can safely be turned off for any EABI user space versions.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index acf5e6f..1c6eb7e 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -28,6 +28,7 @@
#include <linux/tick.h>
#include <linux/utsname.h>
#include <linux/uaccess.h>
+#include <linux/random.h>
#include <asm/leds.h>
#include <asm/processor.h>
@@ -421,3 +422,9 @@
} while (count ++ < 16);
return 0;
}
+
+unsigned long arch_randomize_brk(struct mm_struct *mm)
+{
+ unsigned long range_end = mm->brk + 0x02000000;
+ return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
+}