diff options
Diffstat (limited to 'arch/mips/kernel/syscall.c')
| -rw-r--r-- | arch/mips/kernel/syscall.c | 61 |
1 files changed, 56 insertions, 5 deletions
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c index dd81b0f8751..1dc6edff45e 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) @@ -207,12 +254,14 @@ 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; - error = do_execve(filename, (char __user *__user *) (long)regs.regs[5], - (char __user *__user *) (long)regs.regs[6], ®s); + error = do_execve(filename, + (const char __user *const __user *) (long)regs.regs[5], + (const char __user *const __user *) (long)regs.regs[6], + ®s); putname(filename); out: @@ -389,7 +438,9 @@ asmlinkage void bad_stack(void) * Do a system call from kernel instead of calling sys_execve so we * end up with proper pt_regs. */ -int kernel_execve(const char *filename, char *const argv[], char *const envp[]) +int kernel_execve(const char *filename, + const char *const argv[], + const char *const envp[]) { register unsigned long __a0 asm("$4") = (unsigned long) filename; register unsigned long __a1 asm("$5") = (unsigned long) argv; |