Linux-libre 4.5-gnu

1 files changed, 14 insertions, 7 deletions

diff --git a/mm/mprotect.c b/mm/mprotect.c
index ef5be8eaa..f7cb3d4d9 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -149,7 +149,8 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
 		unsigned long this_pages;
 
 		next = pmd_addr_end(addr, end);
-		if (!pmd_trans_huge(*pmd) && pmd_none_or_clear_bad(pmd))
+		if (!pmd_trans_huge(*pmd) && !pmd_devmap(*pmd)
+				&& pmd_none_or_clear_bad(pmd))
 			continue;
 
 		/* invoke the mmu notifier if the pmd is populated */
@@ -158,10 +159,12 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
 			mmu_notifier_invalidate_range_start(mm, mni_start, end);
 		}
 
-		if (pmd_trans_huge(*pmd)) {
-			if (next - addr != HPAGE_PMD_SIZE)
-				split_huge_page_pmd(vma, addr, pmd);
-			else {
+		if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) {
+			if (next - addr != HPAGE_PMD_SIZE) {
+				split_huge_pmd(vma, pmd, addr);
+				if (pmd_none(*pmd))
+					continue;
+			} else {
 				int nr_ptes = change_huge_pmd(vma, pmd, addr,
 						newprot, prot_numa);
 
@@ -278,6 +281,10 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev,
 	 * even if read-only so there is no need to account for them here
 	 */
 	if (newflags & VM_WRITE) {
+		/* Check space limits when area turns into data. */
+		if (!may_expand_vm(mm, newflags, nrpages) &&
+				may_expand_vm(mm, oldflags, nrpages))
+			return -ENOMEM;
 		if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_HUGETLB|
 						VM_SHARED|VM_NORESERVE))) {
 			charged = nrpages;
@@ -334,8 +341,8 @@ success:
 		populate_vma_page_range(vma, start, end, NULL);
 	}
 
-	vm_stat_account(mm, oldflags, vma->vm_file, -nrpages);
-	vm_stat_account(mm, newflags, vma->vm_file, nrpages);
+	vm_stat_account(mm, oldflags, -nrpages);
+	vm_stat_account(mm, newflags, nrpages);
 	perf_event_mmap(vma);
 	return 0;