Btrfs: deal with enomem in the rewind path

[profile/ivi/kernel-x86-ivi.git] / fs / btrfs / ctree.c

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 0d5c686..1dd8a71 100644 (file)
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1211,7 +1211,11 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
                BUG_ON(tm->slot != 0);
                eb_rewin = alloc_dummy_extent_buffer(eb->start,
                                                fs_info->tree_root->nodesize);
-               BUG_ON(!eb_rewin);
+               if (!eb_rewin) {
+                       btrfs_tree_read_unlock(eb);
+                       free_extent_buffer(eb);
+                       return NULL;
+               }
                btrfs_set_header_bytenr(eb_rewin, eb->start);
                btrfs_set_header_backref_rev(eb_rewin,
                                             btrfs_header_backref_rev(eb));
@@ -1219,7 +1223,11 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
                btrfs_set_header_level(eb_rewin, btrfs_header_level(eb));
        } else {
                eb_rewin = btrfs_clone_extent_buffer(eb);
-               BUG_ON(!eb_rewin);
+               if (!eb_rewin) {
+                       btrfs_tree_read_unlock(eb);
+                       free_extent_buffer(eb);
+                       return NULL;
+               }
        }
 
        btrfs_tree_read_unlock(eb);
@@ -2772,6 +2780,10 @@ again:
                                                          BTRFS_READ_LOCK);
                        }
                        b = tree_mod_log_rewind(root->fs_info, b, time_seq);
+                       if (!b) {
+                               ret = -ENOMEM;
+                               goto done;
+                       }
                        p->locks[level] = BTRFS_READ_LOCK;
                        p->nodes[level] = b;
                } else {