From e8b0d724d596f2ac1264ad830a04ef8e415be956 Mon Sep 17 00:00:00 2001 From: Filipe David Borba Manana Date: Tue, 15 Oct 2013 00:12:27 +0100 Subject: [PATCH] Btrfs: fix btrfs_prev_leaf() previous key computation If we decrement the key type, we must reset its offset to the largest possible offset (u64)-1. If we decrement the key's objectid, then we must reset the key's type and offset to their largest possible values, (u8)-1 and (u64)-1 respectively. Not doing so can make us miss an items in the tree. Signed-off-by: Filipe David Borba Manana Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 8f3d6f893585..a749121203df 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -4827,14 +4827,18 @@ static int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path) btrfs_item_key_to_cpu(path->nodes[0], &key, 0); - if (key.offset > 0) + if (key.offset > 0) { key.offset--; - else if (key.type > 0) + } else if (key.type > 0) { key.type--; - else if (key.objectid > 0) + key.offset = (u64)-1; + } else if (key.objectid > 0) { key.objectid--; - else + key.type = (u8)-1; + key.offset = (u64)-1; + } else { return 1; + } btrfs_release_path(path); ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); -- 2.39.5