3cfdf8fcaa
When cmtp_attach_device fails, cmtp_add_connection returns the error value which leads to the caller to doing fput through sockfd_put. But cmtp_session kthread, which is stopped in this path will also call fput, leading to a potential refcount underflow or a use-after-free. Add a refcount before we signal the kthread to stop. The kthread will try to grab the cmtp_session_sem mutex before doing the fput, which is held when get_file is called, so there should be no races there. Reported-by: Ryota Shiga Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
11 KiB
11 KiB