1 files changed, 49 insertions, 2 deletions

diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index dd81b0f..bddce0b 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -29,6 +29,8 @@
 #include <linux/ipc.h>
 #include <linux/uaccess.h>
 #include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/elf.h>
 
 #include <asm/asm.h>
 #include <asm/branch.h>
@@ -116,7 +118,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 		    (!vmm || addr + len <= vmm->vm_start))
 			return addr;
 	}
-	addr = TASK_UNMAPPED_BASE;
+	addr = current->mm->mmap_base;
 	if (do_color_align)
 		addr = COLOUR_ALIGN(addr, pgoff);
 	else
@@ -134,6 +136,51 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 	}
 }
 
+void arch_pick_mmap_layout(struct mm_struct *mm)
+{
+	unsigned long random_factor = 0UL;
+
+	if (current->flags & PF_RANDOMIZE) {
+		random_factor = get_random_int();
+		random_factor = random_factor << PAGE_SHIFT;
+		if (TASK_IS_32BIT_ADDR)
+			random_factor &= 0xfffffful;
+		else
+			random_factor &= 0xffffffful;
+	}
+
+	mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
+	mm->get_unmapped_area = arch_get_unmapped_area;
+	mm->unmap_area = arch_unmap_area;
+}
+
+static inline unsigned long brk_rnd(void)
+{
+	unsigned long rnd = get_random_int();
+
+	rnd = rnd << PAGE_SHIFT;
+	/* 8MB for 32bit, 256MB for 64bit */
+	if (TASK_IS_32BIT_ADDR)
+		rnd = rnd & 0x7ffffful;
+	else
+		rnd = rnd & 0xffffffful;
+
+	return rnd;
+}
+
+unsigned long arch_randomize_brk(struct mm_struct *mm)
+{
+	unsigned long base = mm->brk;
+	unsigned long ret;
+
+	ret = PAGE_ALIGN(base + brk_rnd());
+
+	if (ret < mm->brk)
+		return mm->brk;
+
+	return ret;
+}
+
 SYSCALL_DEFINE6(mips_mmap, unsigned long, addr, unsigned long, len,
 	unsigned long, prot, unsigned long, flags, unsigned long,
 	fd, off_t, offset)
@@ -207,7 +254,7 @@ asmlinkage int sys_execve(nabi_no_regargs struct pt_regs regs)
 	int error;
 	char * filename;
 
-	filename = getname((char __user *) (long)regs.regs[4]);
+	filename = getname((const char __user *) (long)regs.regs[4]);
 	error = PTR_ERR(filename);
 	if (IS_ERR(filename))
 		goto out;