[PATCH 00/59] LSM: Module stacking for AppArmor

[Stephen Smalley]

On Tue, Apr 9, 2019 at 5:40 PM Casey Schaufler <casey at schaufler-ca.com> wrote:
>
> This patchset provides the changes required for
> the AppArmor security module to stack safely with
> "exclusive" security modules, those being SELinux and
> Smack.

What's the use case?  Who would use such support?

>
> Performance: Using a kernel compile benchmark indicates
> a performance impact of 0.15% for a Fedora 29 system
> with SELinux. Adding AppArmor has an additional 0.20%
> impact. Fedora does not include an AppArmor profile.
>
> A new process attribute identifies which security module
> information should be reported by SO_PEERSEC and the
> /proc/.../attr/current interface. This is provided by
> /proc/.../attr/display. Writing the name of the security
> module desired to this interface will set which LSM hooks
> will be called for this information. The first security
> module providing the hooks will be used by default.
>
> The use of integer based security tokens (secids) is
> generally (but not completely) replaced by a structure
> lsm_export. The lsm_export structure can contain information
> for each of the security modules that export information
> outside the LSM layer.
>
> The LSM interfaces that provide "secctx" text strings
> have been changed to use a structure "lsm_context"
> instead of a pointer/length pair. In some cases the
> interfaces used a "char *" pointer and in others a
> "void *". This was necessary to ensure that the correct
> release mechanism for the text is used. It also makes
> many of the interfaces cleaner.
>
> The security module stacking issues around netlabel
> not addressed here as they are beyond what is required
> to stack AppArmor with either SELinux or Smack.
>
> git://github.com/cschaufler/lsm-stacking.git#stack-5.1-rc2-apparmor
>
> Signed-off-by: Casey Schaufler <casey at schaufler-ca.com>
> ---
>  drivers/android/binder.c                |  25 ++-
>  fs/kernfs/dir.c                         |   6 +-
>  fs/kernfs/inode.c                       |  31 ++-
>  fs/kernfs/kernfs-internal.h             |   3 +-
>  fs/nfs/inode.c                          |  13 +-
>  fs/nfs/internal.h                       |   8 +-
>  fs/nfs/nfs4proc.c                       |  17 +-
>  fs/nfs/nfs4xdr.c                        |  16 +-
>  fs/nfsd/nfs4proc.c                      |   8 +-
>  fs/nfsd/nfs4xdr.c                       |  14 +-
>  fs/nfsd/vfs.c                           |   7 +-
>  fs/proc/base.c                          |   1 +
>  include/linux/cred.h                    |   3 +-
>  include/linux/lsm_hooks.h               |  93 ++++----
>  include/linux/nfs4.h                    |   8 +-
>  include/linux/security.h                | 137 ++++++++----
>  include/net/netlabel.h                  |  10 +-
>  include/net/scm.h                       |  14 +-
>  kernel/audit.c                          |  43 ++--
>  kernel/audit.h                          |   9 +-
>  kernel/auditfilter.c                    |   6 +-
>  kernel/auditsc.c                        |  77 ++++---
>  kernel/cred.c                           |  15 +-
>  net/ipv4/cipso_ipv4.c                   |  13 +-
>  net/ipv4/ip_sockglue.c                  |  12 +-
>  net/netfilter/nf_conntrack_netlink.c    |  29 ++-
>  net/netfilter/nf_conntrack_standalone.c |  16 +-
>  net/netfilter/nfnetlink_queue.c         |  38 ++--
>  net/netfilter/nft_meta.c                |  13 +-
>  net/netfilter/xt_SECMARK.c              |  14 +-
>  net/netlabel/netlabel_kapi.c            |   5 +-
>  net/netlabel/netlabel_unlabeled.c       | 101 +++++----
>  net/netlabel/netlabel_unlabeled.h       |   2 +-
>  net/netlabel/netlabel_user.c            |  13 +-
>  net/netlabel/netlabel_user.h            |   2 +-
>  net/unix/af_unix.c                      |  11 +-
>  security/apparmor/audit.c               |   4 +-
>  security/apparmor/include/audit.h       |   2 +-
>  security/apparmor/include/net.h         |   6 +-
>  security/apparmor/include/secid.h       |   9 +-
>  security/apparmor/lsm.c                 |  64 ++----
>  security/apparmor/secid.c               |  42 ++--
>  security/integrity/ima/ima.h            |  14 +-
>  security/integrity/ima/ima_api.c        |   9 +-
>  security/integrity/ima/ima_appraise.c   |   6 +-
>  security/integrity/ima/ima_main.c       |  34 +--
>  security/integrity/ima/ima_policy.c     |  19 +-
>  security/security.c                     | 366 ++++++++++++++++++++++++++++----
>  security/selinux/hooks.c                | 259 +++++++++++-----------
>  security/selinux/include/audit.h        |   5 +-
>  security/selinux/include/objsec.h       |  42 +++-
>  security/selinux/netlabel.c             |  25 +--
>  security/selinux/ss/services.c          |  18 +-
>  security/smack/smack.h                  |  18 ++
>  security/smack/smack_lsm.c              | 238 +++++++++++----------
>  security/smack/smack_netfilter.c        |   8 +-
>  security/smack/smackfs.c                |  12 +-
>  57 files changed, 1252 insertions(+), 781 deletions(-)