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Date: Tue, 29 Sep 2020 18:13:54 +0000 (UTC)
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Subject: svn commit: r366266 - head/lib/libc/sys
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Author: imp
Date: Tue Sep 29 18:13:54 2020
New Revision: 366266
URL: https://svnweb.freebsd.org/changeset/base/366266

Log:
  Updates to chroot(2) docs
  
  1. Note what settings give historic behavior
  2. Recommend jail under security considerations.

Modified:
  head/lib/libc/sys/chroot.2

Modified: head/lib/libc/sys/chroot.2
==============================================================================
--- head/lib/libc/sys/chroot.2	Tue Sep 29 18:06:02 2020	(r366265)
+++ head/lib/libc/sys/chroot.2	Tue Sep 29 18:13:54 2020	(r366266)
@@ -28,7 +28,7 @@
 .\"     @(#)chroot.2	8.1 (Berkeley) 6/4/93
 .\" $FreeBSD$
 .\"
-.Dd June 26, 2020
+.Dd September 29, 2020
 .Dt CHROOT 2
 .Os
 .Sh NAME
@@ -91,7 +91,10 @@ system call.
 .Pp
 Any other value for
 .Ql kern.chroot_allow_open_directories
-will bypass the check for open directories
+will bypass the check for open directories,
+mimicking the historic insecure behavior of
+.Fn chroot
+still present on other systems.
 .Sh RETURN VALUES
 .Rv -std
 .Sh ERRORS
@@ -156,3 +159,7 @@ root,
 for instance,
 setup the sandbox so that the sandboxed user will have no write
 access to any well-known system directories.
+.Pp
+For complete isolation from the rest of the system, use
+.Xr jail 2
+instead.