1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c
index c194955aecae..249b2896d4ea 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1308,7 +1308,12 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
 	}
 	if (mddev->level != LEVEL_MULTIPATH) {
 		int role;
-		role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
+		if (rdev->desc_nr < 0 ||
+		    rdev->desc_nr >= le32_to_cpu(sb->max_dev)) {
+			role = 0xffff;
+			rdev->desc_nr = -1;
+		} else
+			role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
 		switch(role) {
 		case 0xffff: /* spare */
 			break;