Btrfs: fix array bound checking

Otherwise we can execced the array bound of path->slots[].

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 011cab3aca8..0fe615e4ea3 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -902,9 +902,10 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 
         orig_ptr = btrfs_node_blockptr(mid, orig_slot);
 
-        if (level < BTRFS_MAX_LEVEL - 1)
+        if (level < BTRFS_MAX_LEVEL - 1) {
                 parent = path->nodes[level + 1];
-        pslot = path->slots[level + 1];
+                pslot = path->slots[level + 1];
+        }
 
         /*
          * deal with the case where there is only one pointer in the root
@@ -1107,9 +1108,10 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
         mid = path->nodes[level];
         WARN_ON(btrfs_header_generation(mid) != trans->transid);
 
-        if (level < BTRFS_MAX_LEVEL - 1)
+        if (level < BTRFS_MAX_LEVEL - 1) {
                 parent = path->nodes[level + 1];
-        pslot = path->slots[level + 1];
+                pslot = path->slots[level + 1];
+        }
 
         if (!parent)
                 return 1;