diff mbox series

blk-mq: protect debugfs_create_files() from failures

Message ID 20190123134854.GA25906@kroah.com (mailing list archive)
State New, archived
Headers show
Series blk-mq: protect debugfs_create_files() from failures | expand

Commit Message

Greg Kroah-Hartman Jan. 23, 2019, 1:48 p.m. UTC
If debugfs were to return a non-NULL error for a debugfs call, using
that pointer later in debugfs_create_files() would crash.

Fix that by properly checking the pointer before referencing it.

Reported-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 block/blk-mq-debugfs.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series

Patch

diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 90d68760af08..777638f597aa 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -838,6 +838,9 @@  static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {
 static bool debugfs_create_files(struct dentry *parent, void *data,
 				 const struct blk_mq_debugfs_attr *attr)
 {
+	if (IS_ERR_OR_NULL(parent))
+		return false;
+
 	d_inode(parent)->i_private = data;
 
 	for (; attr->name; attr++) {