1 files changed, 18 insertions, 21 deletions

diff --git a/mm/migrate.c b/mm/migrate.c
index efddbf0926b2..880bd592d38e 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -912,6 +912,9 @@ static int do_pages_move(struct mm_struct *mm, struct task_struct *task,
 				goto out_pm;
 
 			err = -ENODEV;
+			if (node < 0 || node >= MAX_NUMNODES)
+				goto out_pm;
+
 			if (!node_state(node, N_HIGH_MEMORY))
 				goto out_pm;
 
@@ -999,33 +1002,27 @@ static int do_pages_stat(struct mm_struct *mm, unsigned long nr_pages,
 #define DO_PAGES_STAT_CHUNK_NR 16
 	const void __user *chunk_pages[DO_PAGES_STAT_CHUNK_NR];
 	int chunk_status[DO_PAGES_STAT_CHUNK_NR];
-	unsigned long i, chunk_nr = DO_PAGES_STAT_CHUNK_NR;
-	int err;
 
-	for (i = 0; i < nr_pages; i += chunk_nr) {
-		if (chunk_nr > nr_pages - i)
-			chunk_nr = nr_pages - i;
+	while (nr_pages) {
+		unsigned long chunk_nr;
 
-		err = copy_from_user(chunk_pages, &pages[i],
-				     chunk_nr * sizeof(*chunk_pages));
-		if (err) {
-			err = -EFAULT;
-			goto out;
-		}
+		chunk_nr = nr_pages;
+		if (chunk_nr > DO_PAGES_STAT_CHUNK_NR)
+			chunk_nr = DO_PAGES_STAT_CHUNK_NR;
+
+		if (copy_from_user(chunk_pages, pages, chunk_nr * sizeof(*chunk_pages)))
+			break;
 
 		do_pages_stat_array(mm, chunk_nr, chunk_pages, chunk_status);
 
-		err = copy_to_user(&status[i], chunk_status,
-				   chunk_nr * sizeof(*chunk_status));
-		if (err) {
-			err = -EFAULT;
-			goto out;
-		}
-	}
-	err = 0;
+		if (copy_to_user(status, chunk_status, chunk_nr * sizeof(*status)))
+			break;
 
-out:
-	return err;
+		pages += chunk_nr;
+		status += chunk_nr;
+		nr_pages -= chunk_nr;
+	}
+	return nr_pages ? -EFAULT : 0;
 }
 
 /*