If smb2_create_link() is called with ReplaceIfExists set and the name
does exist then a deadlock will happen.
ksmbd_vfs_kern_path_locked() will return with success and the parent
directory will be locked. ksmbd_vfs_remove_file() will then remove the
file. ksmbd_vfs_link() will then be called while the parent is still
locked. It will try to lock the same parent and will deadlock.
This patch moves the ksmbd_vfs_kern_path_unlock() call to *before*
ksmbd_vfs_link() and then simplifies the code, removing the file_present
flag variable.
Signed-off-by: NeilBrown <neil@brown.name>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
d5fc1400a3