Add a function to enable security-related malloc_options.
With and ok deraadt@, something similar has been in the snaps for a while.
Upstream-ID: 43a95523b832b7f3b943d2908662191110c380ed
[servconf.c servconf.h session.c sftp-server.c sftp.h sshd_config]
[sshd_config.5]
add sshd_config ChrootDirectory option to chroot(2) users to a directory
and tweak internal sftp server to work with it (no special files in
chroot required). ok markus@
dtucker@openbsd.org
Damien Miller