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: 6bdf131fac ("Btrfs: don't leak reloc root nodes on error")
Cc: <stable@vger.kernel.org> # 4.9
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Naohiro Aota 2017-08-25 14:15:14 +09:00 committed by David Sterba
parent 67c003f90f
commit bb166d7207

View File

@ -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);
}
}