Btrfs: check return value of read_tree_block()

[firefly-linux-kernel-4.4.55.git] / fs / btrfs / relocation.c

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index c863c844701529c3fc47f173ee51b65b00958c53..58250e09eb056213944db6703d78679fbb94d35f 100644 (file)
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1724,6 +1724,7 @@ again:
 
                        eb = read_tree_block(dest, old_bytenr, blocksize,
                                             old_ptr_gen);
+                       BUG_ON(!eb);
                        btrfs_tree_lock(eb);
                        if (cow) {
                                ret = btrfs_cow_block(trans, dest, eb, parent,
@@ -2513,6 +2514,10 @@ static int do_relocation(struct btrfs_trans_handle *trans,
                blocksize = btrfs_level_size(root, node->level);
                generation = btrfs_node_ptr_generation(upper->eb, slot);
                eb = read_tree_block(root, bytenr, blocksize, generation);
+               if (!eb) {
+                       err = -EIO;
+                       goto next;
+               }
                btrfs_tree_lock(eb);
                btrfs_set_lock_blocking(eb);
 
@@ -2670,6 +2675,7 @@ static int get_tree_block_key(struct reloc_control *rc,
        BUG_ON(block->key_ready);
        eb = read_tree_block(rc->extent_root, block->bytenr,
                             block->key.objectid, block->key.offset);
+       BUG_ON(!eb);
        WARN_ON(btrfs_header_level(eb) != block->level);
        if (block->level == 0)
                btrfs_item_key_to_cpu(eb, &block->key, 0);