diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/hugetlb.c | 29 | ||||
| -rw-r--r-- | mm/mprotect.c | 12 |
2 files changed, 34 insertions, 7 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 20117a4b8ab6..783098f6cf8e 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -565,3 +565,32 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, return i; } + +void hugetlb_change_protection(struct vm_area_struct *vma, + unsigned long address, unsigned long end, pgprot_t newprot) +{ + struct mm_struct *mm = vma->vm_mm; + unsigned long start = address; + pte_t *ptep; + pte_t pte; + + BUG_ON(address >= end); + flush_cache_range(vma, address, end); + + spin_lock(&mm->page_table_lock); + for (; address < end; address += HPAGE_SIZE) { + ptep = huge_pte_offset(mm, address); + if (!ptep) + continue; + if (!pte_none(*ptep)) { + pte = huge_ptep_get_and_clear(mm, address, ptep); + pte = pte_mkhuge(pte_modify(pte, newprot)); + set_huge_pte_at(mm, address, ptep, pte); + lazy_mmu_prot_update(pte); + } + } + spin_unlock(&mm->page_table_lock); + + flush_tlb_range(vma, start, end); +} + diff --git a/mm/mprotect.c b/mm/mprotect.c index 653b8571c1ed..4c14d4289b61 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -124,7 +124,7 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev, * a MAP_NORESERVE private mapping to writable will now reserve. */ if (newflags & VM_WRITE) { - if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_SHARED|VM_HUGETLB))) { + if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_SHARED))) { charged = nrpages; if (security_vm_enough_memory(charged)) return -ENOMEM; @@ -166,7 +166,10 @@ success: */ vma->vm_flags = newflags; vma->vm_page_prot = newprot; - change_protection(vma, start, end, newprot); + if (is_vm_hugetlb_page(vma)) + hugetlb_change_protection(vma, start, end, newprot); + else + change_protection(vma, start, end, newprot); vm_stat_account(mm, oldflags, vma->vm_file, -nrpages); vm_stat_account(mm, newflags, vma->vm_file, nrpages); return 0; @@ -240,11 +243,6 @@ sys_mprotect(unsigned long start, size_t len, unsigned long prot) /* Here we know that vma->vm_start <= nstart < vma->vm_end. */ - if (is_vm_hugetlb_page(vma)) { - error = -EACCES; - goto out; - } - newflags = vm_flags | (vma->vm_flags & ~(VM_READ | VM_WRITE | VM_EXEC)); /* newflags >> 4 shift VM_MAY% in place of VM_% */ |