From 795e9c0981c427928edb9cc1966903f699ce1b11 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Tue, 25 Apr 2017 16:01:17 +0800 Subject: btrfs-progs: Fix memory leak when 0 sized block group item is found When a 0 sized block group item is found, set_extent_bits() will not really set any bits. While set_state_private() still inserts allocated block group cache into block group extent_io_tree. So at close_ctree() time, we won't free the private block group cache stored since we can't find any bit set for the 0 sized block group. To fix it, at btrfs_read_block_groups() we skip any 0 sized block group, so such leak won't happen. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- extent-tree.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'extent-tree.c') diff --git a/extent-tree.c b/extent-tree.c index 3e32e43b..b12ee290 100644 --- a/extent-tree.c +++ b/extent-tree.c @@ -3250,6 +3250,7 @@ int btrfs_read_block_groups(struct btrfs_root *root) } leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + cache = kzalloc(sizeof(*cache), GFP_NOFS); if (!cache) { ret = -ENOMEM; @@ -3266,6 +3267,17 @@ int btrfs_read_block_groups(struct btrfs_root *root) if (found_key.offset == 0) key.objectid++; btrfs_release_path(path); + + /* + * Skip 0 sized block group, don't insert them into block + * group cache tree, as its length is 0, it won't get + * freed at close_ctree() time. + */ + if (found_key.offset == 0) { + free(cache); + continue; + } + cache->flags = btrfs_block_group_flags(&cache->item); bit = 0; if (cache->flags & BTRFS_BLOCK_GROUP_DATA) { -- cgit v1.2.3