diff options
Diffstat (limited to 'mm/mprotect.c')
| -rw-r--r-- | mm/mprotect.c | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/mm/mprotect.c b/mm/mprotect.c index 57577f63b30..17a2b52b753 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -29,8 +29,9 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t newprot) { pte_t *pte; + spinlock_t *ptl; - pte = pte_offset_map(pmd, addr); + pte = pte_offset_map_lock(mm, pmd, addr, &ptl); do { if (pte_present(*pte)) { pte_t ptent; @@ -44,7 +45,7 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd, lazy_mmu_prot_update(ptent); } } while (pte++, addr += PAGE_SIZE, addr != end); - pte_unmap(pte - 1); + pte_unmap_unlock(pte - 1, ptl); } static inline void change_pmd_range(struct mm_struct *mm, pud_t *pud, @@ -88,7 +89,6 @@ static void change_protection(struct vm_area_struct *vma, BUG_ON(addr >= end); pgd = pgd_offset(mm, addr); flush_cache_range(vma, addr, end); - spin_lock(&mm->page_table_lock); do { next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(pgd)) @@ -96,7 +96,6 @@ static void change_protection(struct vm_area_struct *vma, change_pud_range(mm, pgd, addr, next, newprot); } while (pgd++, addr = next, addr != end); flush_tlb_range(vma, start, end); - spin_unlock(&mm->page_table_lock); } static int @@ -125,6 +124,14 @@ 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_RESERVED) { + BUG_ON(oldflags & VM_WRITE); + printk(KERN_WARNING "program %s is using MAP_PRIVATE, " + "PROT_WRITE mprotect of VM_RESERVED memory, " + "which is deprecated. Please report this to " + "linux-kernel@vger.kernel.org\n",current->comm); + return -EACCES; + } if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_SHARED|VM_HUGETLB))) { charged = nrpages; if (security_vm_enough_memory(charged)) @@ -168,8 +175,8 @@ success: vma->vm_flags = newflags; vma->vm_page_prot = newprot; change_protection(vma, start, end, newprot); - __vm_stat_account(mm, oldflags, vma->vm_file, -nrpages); - __vm_stat_account(mm, newflags, vma->vm_file, nrpages); + vm_stat_account(mm, oldflags, vma->vm_file, -nrpages); + vm_stat_account(mm, newflags, vma->vm_file, nrpages); return 0; fail: |