Prior to commit c0371da6047a ("put iov_iter into msghdr") in v3.19, there
was no check that the iovec contained enough bytes for an ICMP header,
and the read loop would walk across neighboring stack contents. Since the
iov_iter conversion, bad arguments are noticed, but the returned error is
EFAULT
From: Kees Cook
Date: Mon, 5 Dec 2016 10:34:38 -0800
> Prior to commit c0371da6047a ("put iov_iter into msghdr") in v3.19, there
> was no check that the iovec contained enough bytes for an ICMP header,
> and the read loop would walk across neighboring stack contents. Since the
> iov_iter conversi
