CVE-2019-19241

In the Linux kernel before 5.4.2, the iouring feature leads to requests that inadvertently have UID 0 and full capabilities, aka CID-181e448d8709. This is related to fs/io-wq.c, fs/iouring.c, and net/socket.c. For example, an attacker can bypass intended restrictions on adding an IPv4 address to the loopback interface. This occurs because IORINGOPSENDMSG operations, although requested in the context of an unprivileged user, are sometimes performed by a kernel worker thread without considering that context.