The U-Boot copy of btrfs_search_slot() returns on error with the nodes
it has descended through still attached to the path. The kernel one
releases the path on any error unless p->skip_release_on_error is set,
and callers written against that convention treat a failed search as
owning nothing. btrfs_size() is one: it returns straight away on a
search error and never reaches its btrfs_release_path() call, so the
attached extent buffer references leak.

Route both error exits through a release of the path. The error
returns of read_node_slot() carry no extra reference, so the path is
the only thing to clean up.

Suggested-by: Qu Wenruo <[email protected]>
Signed-off-by: Cole Munz <[email protected]>
---
 fs/btrfs/ctree.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 8e932adc425d..48c50e556b16 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -425,8 +425,10 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans,
                level = btrfs_header_level(b);
                p->nodes[level] = b;
                ret = check_block(fs_info, p, level);
-               if (ret)
-                       return -1;
+               if (ret) {
+                       ret = -1;
+                       goto err;
+               }
                ret = btrfs_bin_search(b, key, &slot);
                if (level != 0) {
                        if (ret && slot > 0)
@@ -461,8 +463,10 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans,
                                break;
 
                        b = read_node_slot(fs_info, b, slot);
-                       if (!extent_buffer_uptodate(b))
-                               return -EIO;
+                       if (!extent_buffer_uptodate(b)) {
+                               ret = -EIO;
+                               goto err;
+                       }
                } else {
                        p->slots[level] = slot;
                        /*
@@ -479,6 +483,10 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans,
                }
        }
        return 1;
+
+err:
+       btrfs_release_path(p);
+       return ret;
 }
 
 /*
-- 
2.55.0


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