linux-toradex.git/security/apparmor, branch v5.12-rc5

apparmor: handle idmapped mounts

2021-01-24T13:27:20+00:00

The i_uid and i_gid are mostly used when logging for AppArmor. This is
broken in a bunch of places where the global root id is reported instead
of the i_uid or i_gid of the file. Nonetheless, be kind and log the
mapped inode if we're coming from an idmapped mount. If the initial user
namespace is passed nothing changes so non-idmapped mounts will see
identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-26-christian.brauner@ubuntu.com
Signed-off-by: Christian Brauner

fs: make helpers idmap mount aware

2021-01-24T13:27:20+00:00

Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.

As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.

Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig 
Cc: David Howells 
Cc: Al Viro 
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner

xattr: handle idmapped mounts

2021-01-24T13:27:17+00:00

When interacting with extended attributes the vfs verifies that the
caller is privileged over the inode with which the extended attribute is
associated. For posix access and posix default extended attributes a uid
or gid can be stored on-disk. Let the functions handle posix extended
attributes on idmapped mounts. If the inode is accessed through an
idmapped mount we need to map it according to the mount's user
namespace. Afterwards the checks are identical to non-idmapped mounts.
This has no effect for e.g. security xattrs since they don't store uids
or gids and don't perform permission checks on them like posix acls do.

Link: https://lore.kernel.org/r/20210121131959.646623-10-christian.brauner@ubuntu.com
Cc: Christoph Hellwig 
Cc: David Howells 
Cc: Al Viro 
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig 
Reviewed-by: James Morris 
Signed-off-by: Tycho Andersen 
Signed-off-by: Christian Brauner

apparmor: remove duplicate macro list_entry_is_head()

2020-12-16T06:46:19+00:00

Strangely I hadn't had noticed the existence of the list_entry_is_head()
in apparmor code when added the same one in the list.h.  Luckily it's
fully identical and didn't break builds.  In any case we don't need a
duplicate anymore, thus remove it from apparmor code.

Link: https://lkml.kernel.org/r/20201208100639.88182-1-andriy.shevchenko@linux.intel.com
Fixes: e130816164e244 ("include/linux/list.h: add a macro to test if entry is pointing to the head")
Signed-off-by: Andy Shevchenko 
Acked-by: John Johansen 
Cc: James Morris 
Cc: "Serge E . Hallyn " 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

security: add const qualifier to struct sock in various places

2020-12-03T20:56:03+00:00

A followup change to tcp_request_sock_op would have to drop the 'const'
qualifier from the 'route_req' function as the
'security_inet_conn_request' call is moved there - and that function
expects a 'struct sock *'.

However, it turns out its also possible to add a const qualifier to
security_inet_conn_request instead.

Signed-off-by: Florian Westphal 
Acked-by: James Morris 
Signed-off-by: Jakub Kicinski

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva

Merge tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2020-08-11T21:30:36+00:00

Pull security subsystem updates from James Morris:
 "A couple of minor documentation updates only for this release"

* tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  LSM: drop duplicated words in header file comments
  Replace HTTP links with HTTPS ones: security

mm, treewide: rename kzfree() to kfree_sensitive()

2020-08-07T18:33:22+00:00

As said by Linus:

  A symmetric naming is only helpful if it implies symmetries in use.
  Otherwise it's actively misleading.

  In "kzalloc()", the z is meaningful and an important part of what the
  caller wants.

  In "kzfree()", the z is actively detrimental, because maybe in the
  future we really _might_ want to use that "memfill(0xdeadbeef)" or
  something. The "zero" part of the interface isn't even _relevant_.

The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.

Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.

The renaming is done by using the command sequence:

  git grep -w --name-only kzfree |\
  xargs sed -i 's/kzfree/kfree_sensitive/'

followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.

[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]

Suggested-by: Joe Perches 
Signed-off-by: Waiman Long 
Signed-off-by: Andrew Morton 
Acked-by: David Howells 
Acked-by: Michal Hocko 
Acked-by: Johannes Weiner 
Cc: Jarkko Sakkinen 
Cc: James Morris 
Cc: "Serge E. Hallyn" 
Cc: Joe Perches 
Cc: Matthew Wilcox 
Cc: David Rientjes 
Cc: Dan Carpenter 
Cc: "Jason A . Donenfeld" 
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds

Replace HTTP links with HTTPS ones: security

2020-08-06T19:00:05+00:00

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
          If both the HTTP and HTTPS versions
          return 200 OK and serve the same content:
            Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov 
Acked-by: John Johansen 
Signed-off-by: James Morris

audit: purge audit_log_string from the intra-kernel audit API

2020-07-21T15:12:31+00:00

audit_log_string() was inteded to be an internal audit function and
since there are only two internal uses, remove them.  Purge all external
uses of it by restructuring code to use an existing audit_log_format()
or using audit_log_format().

Please see the upstream issue
https://github.com/linux-audit/audit-kernel/issues/84

Signed-off-by: Richard Guy Briggs 
Signed-off-by: Paul Moore