Merge tag 'fbdev-fixes-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba...

[linux-drm-fsl-dcu.git] / arch / s390 / lib / uaccess_pt.c

diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c
index 97e03caf782598a20857ab276ff03df701c4c3f9..dbdab3e7a1a6266ca3b96cd692d298896bc9902f 100644 (file)
--- a/arch/s390/lib/uaccess_pt.c
+++ b/arch/s390/lib/uaccess_pt.c
@@ -78,11 +78,14 @@ static size_t copy_in_kernel(size_t count, void __user *to,
  * contains the (negative) exception code.
  */
 #ifdef CONFIG_64BIT
+
 static unsigned long follow_table(struct mm_struct *mm,
                                  unsigned long address, int write)
 {
        unsigned long *table = (unsigned long *)__pa(mm->pgd);
 
+       if (unlikely(address > mm->context.asce_limit - 1))
+               return -0x38UL;
        switch (mm->context.asce_bits & _ASCE_TYPE_MASK) {
        case _ASCE_TYPE_REGION1:
                table = table + ((address >> 53) & 0x7ff);