From bb166d7207432d3c7d10c45dc052f12ba3a2121d Mon Sep 17 00:00:00 2001 From: Naohiro Aota Date: Fri, 25 Aug 2017 14:15:14 +0900 Subject: [PATCH] btrfs: fix NULL pointer dereference from free_reloc_roots() __del_reloc_root should be called before freeing up reloc_root->node. If not, calling __del_reloc_root() dereference reloc_root->node, causing the system BUG. Fixes: 6bdf131fac23 ("Btrfs: don't leak reloc root nodes on error") Cc: # 4.9 Signed-off-by: Naohiro Aota Reviewed-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/relocation.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index 3a49a3c2fca4..9841faef08ea 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -2400,11 +2400,11 @@ void free_reloc_roots(struct list_head *list) while (!list_empty(list)) { reloc_root = list_entry(list->next, struct btrfs_root, root_list); + __del_reloc_root(reloc_root); free_extent_buffer(reloc_root->node); free_extent_buffer(reloc_root->commit_root); reloc_root->node = NULL; reloc_root->commit_root = NULL; - __del_reloc_root(reloc_root); } } -- 2.20.1