linux-stable/security
Mickaël Salaün cb2c7d1a17 landlock: Support filesystem access-control
Using Landlock objects and ruleset, it is possible to tag inodes
according to a process's domain.  To enable an unprivileged process to
express a file hierarchy, it first needs to open a directory (or a file)
and pass this file descriptor to the kernel through
landlock_add_rule(2).  When checking if a file access request is
allowed, we walk from the requested dentry to the real root, following
the different mount layers.  The access to each "tagged" inodes are
collected according to their rule layer level, and ANDed to create
access to the requested file hierarchy.  This makes possible to identify
a lot of files without tagging every inodes nor modifying the
filesystem, while still following the view and understanding the user
has from the filesystem.

Add a new ARCH_EPHEMERAL_INODES for UML because it currently does not
keep the same struct inodes for the same inodes whereas these inodes are
in use.

This commit adds a minimal set of supported filesystem access-control
which doesn't enable to restrict all file-related actions.  This is the
result of multiple discussions to minimize the code of Landlock to ease
review.  Thanks to the Landlock design, extending this access-control
without breaking user space will not be a problem.  Moreover, seccomp
filters can be used to restrict the use of syscall families which may
not be currently handled by Landlock.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jann Horn <jannh@google.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Link: https://lore.kernel.org/r/20210422154123.13086-8-mic@digikod.net
Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2021-04-22 12:22:11 -07:00
..
apparmor apparmor: handle idmapped mounts 2021-01-24 14:27:20 +01:00
bpf bpf: Implement task local storage 2020-11-06 08:08:37 -08:00
integrity Keyrings miscellany 2021-02-23 16:09:23 -08:00
keys Keyrings miscellany 2021-02-23 16:09:23 -08:00
landlock landlock: Support filesystem access-control 2021-04-22 12:22:11 -07:00
loadpin LSM: Add "contents" flag to kernel_read_file hook 2020-10-05 13:37:03 +02:00
lockdown Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2020-06-02 17:36:24 -07:00
safesetid LSM: SafeSetID: Fix warnings reported by test bot 2020-10-13 09:17:36 -07:00
selinux LSM: Infrastructure management of the superblock 2021-04-22 12:22:10 -07:00
smack LSM: Infrastructure management of the superblock 2021-04-22 12:22:10 -07:00
tomoyo tomoyo: recognize kernel threads correctly 2021-02-01 11:53:05 +09:00
yama task_work: cleanup notification modes 2020-10-17 15:05:30 -06:00
commoncap.c Revert 95ebabde38 ("capabilities: Don't allow writing ambiguous v3 file capabilities") 2021-03-12 15:27:14 -06:00
device_cgroup.c device_cgroup: Fix RCU list debugging warning 2020-08-20 11:25:03 -07:00
inode.c Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
Kconfig landlock: Set up the security framework and manage credentials 2021-04-22 12:22:10 -07:00
Kconfig.hardening security: allow using Clang's zero initialization for stack variables 2020-06-16 02:06:23 -07:00
lsm_audit.c make dump_common_audit_data() safe to be called from RCU pathwalk 2021-01-16 15:12:08 -05:00
Makefile landlock: Add object management 2021-04-22 12:22:10 -07:00
min_addr.c sysctl: pass kernel pointers to ->proc_handler 2020-04-27 02:07:40 -04:00
security.c LSM: Infrastructure management of the superblock 2021-04-22 12:22:10 -07:00