s390/mm: use generic mm_hooks

CVE-2017-5754

With git commit 3446c13b268af86391d06611327006b059b8bab1
"s390/mm: four page table levels vs. fork"
s390 dropped its architecture specific version of arch_dup_mmap.

Now all functions defined by include/asm-generic/mm_hooks.h are
identical to the s390 versions. Use the generic header.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
(cherry picked from commit 8e58ab5c6563e3cc94029853471a36b87b4716eb)
Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>

diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h
index ebfb2f248ae981ac7a47d2203915d46ab79eba2e..baaa58d25ad06b62ac786030934050446b684cda 100644 (file)
--- a/arch/s390/include/asm/mmu_context.h
+++ b/arch/s390/include/asm/mmu_context.h
@@ -12,6 +12,7 @@
 #include <linux/mm_types.h>
 #include <asm/tlbflush.h>
 #include <asm/ctl_reg.h>
+#include <asm-generic/mm_hooks.h>
 
 static inline int init_new_context(struct task_struct *tsk,
                                   struct mm_struct *mm)
@@ -138,30 +139,4 @@ static inline void activate_mm(struct mm_struct *prev,
        set_user_asce(next);
 }
 
-static inline void arch_dup_mmap(struct mm_struct *oldmm,
-                                struct mm_struct *mm)
-{
-}
-
-static inline void arch_exit_mmap(struct mm_struct *mm)
-{
-}
-
-static inline void arch_unmap(struct mm_struct *mm,
-                       struct vm_area_struct *vma,
-                       unsigned long start, unsigned long end)
-{
-}
-
-static inline void arch_bprm_mm_init(struct mm_struct *mm,
-                                    struct vm_area_struct *vma)
-{
-}
-
-static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
-               bool write, bool execute, bool foreign)
-{
-       /* by default, allow everything */
-       return true;
-}
 #endif /* __S390_MMU_CONTEXT_H */