Commit Graph

472 Commits

Author SHA1 Message Date
Linus Torvalds 57bb8e37d7 + Cleanups
- apparmor: remove no-op permission check in policy_unpack
 
 + Bug fixes
   - apparmor: fix an error code in __aa_create_ns()
   - apparmor: Fix failure to audit context info in build_change_hat
   - apparmor: Check buffer bounds when mapping permissions mask
   - apparmor: Fully initialize aa_perms struct when answering userspace query
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Merge tag 'apparmor-pr-2018-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "There is nothing major this time just four bug fixes and a patch to
  remove some dead code:

  Cleanups:
   - remove no-op permission check in policy_unpack

  Bug fixes:
   - fix an error code in __aa_create_ns()
   - fix failure to audit context info in build_change_hat
   - check buffer bounds when mapping permissions mask
   - fully initialize aa_perms struct when answering userspace query"

* tag 'apparmor-pr-2018-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
  apparmor: remove no-op permission check in policy_unpack
  apparmor: fix an error code in __aa_create_ns()
  apparmor: Fix failure to audit context info in build_change_hat
  apparmor: Fully initialize aa_perms struct when answering userspace query
  apparmor: Check buffer bounds when mapping permissions mask
2018-08-24 13:00:33 -07:00
John Johansen c037bd6158 apparmor: remove no-op permission check in policy_unpack
The patch 736ec752d95e: "AppArmor: policy routines for loading and
unpacking policy" from Jul 29, 2010, leads to the following static
checker warning:

    security/apparmor/policy_unpack.c:410 verify_accept()
    warn: bitwise AND condition is false here

    security/apparmor/policy_unpack.c:413 verify_accept()
    warn: bitwise AND condition is false here

security/apparmor/policy_unpack.c
   392  #define DFA_VALID_PERM_MASK             0xffffffff
   393  #define DFA_VALID_PERM2_MASK            0xffffffff
   394
   395  /**
   396   * verify_accept - verify the accept tables of a dfa
   397   * @dfa: dfa to verify accept tables of (NOT NULL)
   398   * @flags: flags governing dfa
   399   *
   400   * Returns: 1 if valid accept tables else 0 if error
   401   */
   402  static bool verify_accept(struct aa_dfa *dfa, int flags)
   403  {
   404          int i;
   405
   406          /* verify accept permissions */
   407          for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
   408                  int mode = ACCEPT_TABLE(dfa)[i];
   409
   410                  if (mode & ~DFA_VALID_PERM_MASK)
   411                          return 0;
   412
   413                  if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK)
   414                          return 0;

fixes: 736ec752d9 ("AppArmor: policy routines for loading and unpacking policy")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-08-22 18:44:42 -07:00
Dan Carpenter 0a6b29230e apparmor: fix an error code in __aa_create_ns()
We should return error pointers in this function.  Returning NULL
results in a NULL dereference in the caller.

Fixes: 73688d1ed0 ("apparmor: refactor prepare_ns() and make usable from different views")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-08-21 16:24:56 -07:00
John Johansen 24b87a16fe apparmor: Fix failure to audit context info in build_change_hat
Cleans up clang warning:
warning: variable 'info' set but not used [-Wunused-but-set-variable]

Fixes: 89dbf1962a ("apparmor: move change_hat mediation to using labels")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-07-20 03:25:25 -07:00
Tyler Hicks f4585bc20f apparmor: Fully initialize aa_perms struct when answering userspace query
Fully initialize the aa_perms struct in profile_query_cb() to avoid the
potential of using an uninitialized struct member's value in a response
to a query from userspace.

Detected by CoverityScan CID#1415126 ("Uninitialized scalar variable")

Fixes: 4f3b3f2d79 ("apparmor: add profile permission query ability")
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-07-19 16:29:13 -07:00
Tyler Hicks 7f3ebcf2b1 apparmor: Check buffer bounds when mapping permissions mask
Don't read past the end of the buffer containing permissions
characters or write past the end of the destination string.

Detected by CoverityScan CID#1415361, 1415376 ("Out-of-bounds access")

Fixes: e53cfe6c7c ("apparmor: rework perm mapping to a slightly broader set")
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-07-19 16:24:43 -07:00
Al Viro 9481769208 ->file_open(): lose cred argument
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12 10:04:15 -04:00
Linus Torvalds 463f202172 + Features
- add support for mapping secids and using secctxes
   - add the ability to get a task's secid
   - add support for audit rule filtering
 
 + Cleanups
   - multiple typo fixes
   - Convert to use match_string() helper
   - update git and wiki locations in AppArmor docs
   - improve get_buffers macro by using get_cpu_ptr
   - Use an IDR to allocate apparmor secids
 
 + Bug fixes
   - fix '*seclen' is never less than zero
   - fix mediation of prlimit
   - fix memory leak when deduping profile load
   - fix ptrace read check
   - fix memory leak of rule on error exit path
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Merge tag 'apparmor-pr-2018-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull AppArmor updates from John Johansen:
 "Features
   - add support for mapping secids and using secctxes
   - add the ability to get a task's secid
   - add support for audit rule filtering

  Cleanups:
   - multiple typo fixes
   - Convert to use match_string() helper
   - update git and wiki locations in AppArmor docs
   - improve get_buffers macro by using get_cpu_ptr
   - Use an IDR to allocate apparmor secids

  Bug fixes:
   - fix '*seclen' is never less than zero
   - fix mediation of prlimit
   - fix memory leak when deduping profile load
   - fix ptrace read check
   - fix memory leak of rule on error exit path"

* tag 'apparmor-pr-2018-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (21 commits)
  apparmor: fix ptrace read check
  apparmor: fix memory leak when deduping profile load
  apparmor: fix mediation of prlimit
  apparmor: fixup secid map conversion to using IDR
  apparmor: Use an IDR to allocate apparmor secids
  apparmor: Fix memory leak of rule on error exit path
  apparmor: modify audit rule support to support profile stacks
  apparmor: Add support for audit rule filtering
  apparmor: update git and wiki locations in AppArmor docs
  apparmor: Convert to use match_string() helper
  apparmor: improve get_buffers macro by using get_cpu_ptr
  apparmor: fix '*seclen' is never less than zero
  apparmor: fix typo "preconfinement"
  apparmor: fix typo "independent"
  apparmor: fix typo "traverse"
  apparmor: fix typo "type"
  apparmor: fix typo "replace"
  apparmor: fix typo "comparison"
  apparmor: fix typo "loosen"
  apparmor: add the ability to get a task's secid
  ...
2018-06-14 16:11:28 +09:00
Kees Cook 6396bb2215 treewide: kzalloc() -> kcalloc()
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
John Johansen 338d0be437 apparmor: fix ptrace read check
The ptrace read check is incorrect resulting in policy that is
broader than it needs to be. Fix the check so that read access
permission can be properly detected when other ptrace flags are
set.

Fixes: b2d09ae449 ("apparmor: move ptrace checks to using labels")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:51:02 -07:00
John Johansen 3ddae9876a apparmor: fix memory leak when deduping profile load
AppArmor is leaking the newly loaded profile and its proxy when
the profile is an exact match to the currently loaded version.

In this case the dedup check results in the profile being skipped and
put without dealing with the proxy ref thus not breaking a circular
refcount and causing a leak.

BugLink: http://bugs.launchpad.net/bugs/1750594
Fixes: 5d5182cae4 ("apparmor: move to per loaddata files, instead of replicating in profiles")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:51:01 -07:00
John Johansen 11c92f144b apparmor: fix mediation of prlimit
For primit apparmor requires that if target confinement does not match
the setting task's confinement, the setting task requires CAP_SYS_RESOURCE.

Unfortunately this was broken when rlimit enforcement was reworked to
support labels.

Fixes: 86b92cb782 ("apparmor: move resource checks to using labels")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:51:01 -07:00
John Johansen a4c3f89c9b apparmor: fixup secid map conversion to using IDR
The IDR conversion did not handle an error case for when allocating a
mapping fails, and it did not ensure that mappings did not allocate or
use a 0 value, which is used as an invalid secid. Which is used when a
mapping fails.

Fixes: 3ae7eb49a2be ("apparmor: Use an IDR to allocate apparmor secids")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:50:49 -07:00
Matthew Wilcox 99cc45e486 apparmor: Use an IDR to allocate apparmor secids
Replace the custom usage of the radix tree to store a list of free IDs
with the IDR.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:50:49 -07:00
Tyler Hicks 52e8c38001 apparmor: Fix memory leak of rule on error exit path
Currently on the error exit path the allocated rule is not free'd
causing a memory leak. Fix this by calling aa_audit_rule_free().

Detected by CoverityScan, CID#1468966 ("Resource leaks")

Fixes: cb740f574c7b ("apparmor: modify audit rule support to support profile stacks")
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:50:48 -07:00
John Johansen 2ab47dae54 apparmor: modify audit rule support to support profile stacks
Allows for audit rules, where a rule could specify a profile stack
A//&B, while extending the current semantic so if the label specified
in the audit rule is a subset of the secid it is considered a match.

Eg. if the secid resolves to the label stack A//&B//&C

Then an audit rule specifying a label of

  A - would match
  B - would match
  C - would match
  D - would not
  A//&B - would match as a subset
  A//&C - would match as a subset
  B//&C - would match as a subset
  A//&B//&C - would match

  A//&D - would not match, because while A does match, D is also
  specified and does not

Note: audit rules are currently assumed to be coming from the root
namespace.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:50:48 -07:00
Matthew Garrett e79c26d040 apparmor: Add support for audit rule filtering
This patch adds support to Apparmor for integrating with audit rule
filtering. Right now it only handles SUBJ_ROLE, interpreting it as a
single component of a label. This is sufficient to get Apparmor working
with IMA's appraisal rules without any modifications on the IMA side.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:50:47 -07:00
Andy Shevchenko 5d8779a5cd apparmor: Convert to use match_string() helper
The new helper returns index of the matching string in an array.
We are going to use it here.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jay Freyensee <why2jjj.linux@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-06-07 01:50:40 -07:00
John Johansen 38125c2c2b apparmor: improve get_buffers macro by using get_cpu_ptr
Refactor get_buffers so the cpu_ptr can be obtained in the outer
layer, instead of inside the macro.

This also enables us to cleanup the code and use get_cpu_ptr,
to handle the preempt_disable()

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2018-06-07 01:49:21 -07:00
John Johansen 52e7128ebb apparmor: fix '*seclen' is never less than zero
smatch warnings:
security/apparmor/secid.c:162 apparmor_secid_to_secctx() warn: unsigned '*seclen' is never less than zero.

vim +162 security/apparmor/secid.c

   140
   141	int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
   142	{
   143		/* TODO: cache secctx and ref count so we don't have to recreate */
   144		struct aa_label *label = aa_secid_to_label(secid);
   145
   146		AA_BUG(!secdata);
   147		AA_BUG(!seclen);
   148
   149		if (!label)
   150			return -EINVAL;
   151
   152		if (secdata)
   153			*seclen = aa_label_asxprint(secdata, root_ns, label,
   154						    FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
   155						    FLAG_HIDDEN_UNCONFINED |
   156						    FLAG_ABS_ROOT, GFP_ATOMIC);
   157		else
   158			*seclen = aa_label_snxprint(NULL, 0, root_ns, label,
   159						    FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
   160						    FLAG_HIDDEN_UNCONFINED |
   161						    FLAG_ABS_ROOT);
 > 162		if (*seclen < 0)
   163			return -ENOMEM;
   164
   165		return 0;
   166	}
   167

Fixes: c092921219 ("apparmor: add support for mapping secids and using secctxes")
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-08 08:34:08 -07:00
Zygmunt Krynicki 3107e8cb92 apparmor: fix typo "preconfinement"
Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-03 00:50:46 -07:00
Zygmunt Krynicki 68a1a0c68c apparmor: fix typo "independent"
Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-03 00:50:30 -07:00
Zygmunt Krynicki 5d2371e123 apparmor: fix typo "traverse"
Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-03 00:50:12 -07:00
Zygmunt Krynicki 69ad4a44a2 apparmor: fix typo "type"
Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-03 00:49:56 -07:00
Zygmunt Krynicki b62fb22674 apparmor: fix typo "replace"
Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-03 00:49:35 -07:00
Zygmunt Krynicki a18f902888 apparmor: fix typo "comparison"
Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-03 00:48:58 -07:00
Zygmunt Krynicki b2c2086c39 apparmor: fix typo "loosen"
Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-03 00:47:56 -07:00
John Johansen a7ae3645f5 apparmor: add the ability to get a task's secid
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-02 00:49:11 -07:00
John Johansen c092921219 apparmor: add support for mapping secids and using secctxes
Use a radix tree to provide a map between the secid and the label,
and along with it a basic ability to provide secctx conversion.

Shared/cached secctx will be added later.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-05-02 00:48:55 -07:00
Linus Torvalds 80a17a5f50 + Features
- add base infrastructure for socket mediation. ABI bump and
     additional checks to ensure only v8 compliant policy uses
     socket af mediation.
   - improve and cleanup dfa verification
   - improve profile attachment logic
     - improve overlapping expression handling
     - add the xattr matching to the attachment logic
   - improve signal mediation handling with stacked labels
   - improve handling of no_new_privs in a label stack
 
 + Cleanups and changes
   - use dfa to parse string split
   - bounded version of label_parse
   - proper line wrap nulldfa.in
   - split context out into task and cred naming to better match usage
   - simplify code in aafs
 
 + Bug fixes
   - fix display of .ns_name for containers
   - fix resource audit messages when auditing peer
   - fix logging of the existence test for signals
   - fix resource audit messages when auditing peer
   - fix display of .ns_name for containers
   - fix an error code in verify_table_headers()
   - fix memory leak on buffer on error exit path
   - fix error returns checks by making size a ssize_t
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Merge tag 'apparmor-pr-2018-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "Features:
  - add base infrastructure for socket mediation. ABI bump and
    additional checks to ensure only v8 compliant policy uses socket af
    mediation.
  - improve and cleanup dfa verification
  - improve profile attachment logic
     - improve overlapping expression handling
     - add the xattr matching to the attachment logic
  - improve signal mediation handling with stacked labels
  - improve handling of no_new_privs in a label stack

  Cleanups and changes:
  - use dfa to parse string split
  - bounded version of label_parse
  - proper line wrap nulldfa.in
  - split context out into task and cred naming to better match usage
  - simplify code in aafs

  Bug fixes:
  - fix display of .ns_name for containers
  - fix resource audit messages when auditing peer
  - fix logging of the existence test for signals
  - fix resource audit messages when auditing peer
  - fix display of .ns_name for containers
  - fix an error code in verify_table_headers()
  - fix memory leak on buffer on error exit path
  - fix error returns checks by making size a ssize_t"

* tag 'apparmor-pr-2018-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (36 commits)
  apparmor: fix memory leak on buffer on error exit path
  apparmor: fix dangling symlinks to policy rawdata after replacement
  apparmor: Fix an error code in verify_table_headers()
  apparmor: fix error returns checks by making size a ssize_t
  apparmor: update MAINTAINERS file git and wiki locations
  apparmor: remove POLICY_MEDIATES_SAFE
  apparmor: add base infastructure for socket mediation
  apparmor: improve overlapping domain attachment resolution
  apparmor: convert attaching profiles via xattrs to use dfa matching
  apparmor: Add support for attaching profiles via xattr, presence and value
  apparmor: cleanup: simplify code to get ns symlink name
  apparmor: cleanup create_aafs() error path
  apparmor: dfa split verification of table headers
  apparmor: dfa add support for state differential encoding
  apparmor: dfa move character match into a macro
  apparmor: update domain transitions that are subsets of confinement at nnp
  apparmor: move context.h to cred.h
  apparmor: move task related defines and fns to task.X files
  apparmor: cleanup, drop unused fn __aa_task_is_confined()
  apparmor: cleanup fixup description of aa_replace_profiles
  ...
2018-04-13 15:38:53 -07:00
Linus Torvalds 3612605a5a Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull general security layer updates from James Morris:

 - Convert security hooks from list to hlist, a nice cleanup, saving
   about 50% of space, from Sargun Dhillon.

 - Only pass the cred, not the secid, to kill_pid_info_as_cred and
   security_task_kill (as the secid can be determined from the cred),
   from Stephen Smalley.

 - Close a potential race in kernel_read_file(), by making the file
   unwritable before calling the LSM check (vs after), from Kees Cook.

* 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  security: convert security hooks to use hlist
  exec: Set file unwritable before LSM check
  usb, signal, security: only pass the cred, not the secid, to kill_pid_info_as_cred and security_task_kill
2018-04-07 11:11:41 -07:00
Randy Dunlap 514c603249 headers: untangle kmemleak.h from mm.h
Currently <linux/slab.h> #includes <linux/kmemleak.h> for no obvious
reason.  It looks like it's only a convenience, so remove kmemleak.h
from slab.h and add <linux/kmemleak.h> to any users of kmemleak_* that
don't already #include it.  Also remove <linux/kmemleak.h> from source
files that do not use it.

This is tested on i386 allmodconfig and x86_64 allmodconfig.  It would
be good to run it through the 0day bot for other $ARCHes.  I have
neither the horsepower nor the storage space for the other $ARCHes.

Update: This patch has been extensively build-tested by both the 0day
bot & kisskb/ozlabs build farms.  Both of them reported 2 build failures
for which patches are included here (in v2).

[ slab.h is the second most used header file after module.h; kernel.h is
  right there with slab.h. There could be some minor error in the
  counting due to some #includes having comments after them and I didn't
  combine all of those. ]

[akpm@linux-foundation.org: security/keys/big_key.c needs vmalloc.h, per sfr]
Link: http://lkml.kernel.org/r/e4309f98-3749-93e1-4bb7-d9501a39d015@infradead.org
Link: http://kisskb.ellerman.id.au/kisskb/head/13396/
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>	[2 build failures]
Reported-by: Fengguang Wu <fengguang.wu@intel.com>	[2 build failures]
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:27 -07:00
Colin Ian King 588558eb6d apparmor: fix memory leak on buffer on error exit path
Currently on the error exit path the allocated buffer is not free'd
causing a memory leak. Fix this by kfree'ing it.

Detected by CoverityScan, CID#1466876 ("Resource leaks")

Fixes: 1180b4c757 ("apparmor: fix dangling symlinks to policy rawdata after replacement")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-03-30 21:14:04 -07:00
Alexei Starovoitov cf14f27f82 macro: introduce COUNT_ARGS() macro
move COUNT_ARGS() macro from apparmor to generic header and extend it
to count till twelve.

COUNT() was an alternative name for this logic, but it's used for
different purpose in many other places.

Similarly for CONCATENATE() macro.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-28 22:55:19 +02:00
John Johansen 1180b4c757 apparmor: fix dangling symlinks to policy rawdata after replacement
When policy replacement occurs the symlinks in the profile directory
need to be updated to point to the new rawdata, otherwise once the
old rawdata is removed the symlink becomes broken.

Fix this by dynamically generating the symlink everytime it is read.
These links are used enough that their value needs to be cached and
this way we can avoid needing locking to read and update the link
value.

Fixes: a481f4d917 ("apparmor: add custom apparmorfs that will be used by policy namespace files")
BugLink: http://bugs.launchpad.net/bugs/1755563
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-03-23 17:33:52 -07:00
Dan Carpenter d53c9f4d21 apparmor: Fix an error code in verify_table_headers()
We accidentally return a positive EPROTO instead of a negative -EPROTO.
Since 71 is not an error pointer, that means it eventually results in an
Oops in the caller.

Fixes: d901d6a298 ("apparmor: dfa split verification of table headers")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-03-23 17:28:38 -07:00
Colin Ian King a61ecd329c apparmor: fix error returns checks by making size a ssize_t
Currently variable size is a unsigned size_t, hence comparisons to
see if it is less than zero (for error checking) will always be
false.  Fix this by making size a ssize_t

Detected by CoverityScan, CID#1466080 ("Unsigned compared against 0")

Fixes: 8e51f9087f ("apparmor: Add support for attaching profiles via xattr, presence and value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-03-23 17:25:25 -07:00
John Johansen b9590ad4c4 apparmor: remove POLICY_MEDIATES_SAFE
The unpack code now makes sure every profile has a dfa so the safe
version of POLICY_MEDIATES is no longer needed.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-03-13 17:25:49 -07:00
John Johansen 56974a6fcf apparmor: add base infastructure for socket mediation
version 2 - Force an abi break. Network mediation will only be
            available in v8 abi complaint policy.

Provide a basic mediation of sockets. This is not a full net mediation
but just whether a spcific family of socket can be used by an
application, along with setting up some basic infrastructure for
network mediation to follow.

the user space rule hav the basic form of
  NETWORK RULE = [ QUALIFIERS ] 'network' [ DOMAIN ]
                 [ TYPE | PROTOCOL ]

  DOMAIN = ( 'inet' | 'ax25' | 'ipx' | 'appletalk' | 'netrom' |
             'bridge' | 'atmpvc' | 'x25' | 'inet6' | 'rose' |
	     'netbeui' | 'security' | 'key' | 'packet' | 'ash' |
	     'econet' | 'atmsvc' | 'sna' | 'irda' | 'pppox' |
	     'wanpipe' | 'bluetooth' | 'netlink' | 'unix' | 'rds' |
	     'llc' | 'can' | 'tipc' | 'iucv' | 'rxrpc' | 'isdn' |
	     'phonet' | 'ieee802154' | 'caif' | 'alg' | 'nfc' |
	     'vsock' | 'mpls' | 'ib' | 'kcm' ) ','

  TYPE = ( 'stream' | 'dgram' | 'seqpacket' |  'rdm' | 'raw' |
           'packet' )

  PROTOCOL = ( 'tcp' | 'udp' | 'icmp' )

eg.
  network,
  network inet,

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2018-03-13 17:25:48 -07:00
Stephen Smalley 6b4f3d0105 usb, signal, security: only pass the cred, not the secid, to kill_pid_info_as_cred and security_task_kill
commit d178bc3a70 ("user namespace: usb:
 make usb urbs user namespace aware (v2)") changed kill_pid_info_as_uid
to kill_pid_info_as_cred, saving and passing a cred structure instead of
uids.  Since the secid can be obtained from the cred, drop the secid fields
from the usb_dev_state and async structures, and drop the secid argument to
kill_pid_info_as_cred.  Replace the secid argument to security_task_kill
with the cred.  Update SELinux, Smack, and AppArmor to use the cred, which
avoids the need for Smack and AppArmor to use a secid at all in this hook.
Further changes to Smack might still be required to take full advantage of
this change, since it should now be possible to perform capability
checking based on the supplied cred.  The changes to Smack and AppArmor
have only been compile-tested.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
2018-03-07 09:05:53 +11:00
Linus Torvalds a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
John Johansen 21f6066105 apparmor: improve overlapping domain attachment resolution
Overlapping domain attachments using the current longest left exact
match fail in some simple cases, and with the fix to ensure consistent
behavior by failing unresolvable attachments it becomes important to
do a better job.

eg. under the current match the following are unresolvable where
the alternation is clearly a better match under the most specific
left match rule.
  /**
  /{bin/,}usr/

Use a counting match that detects when a loop in the state machine is
enter, and return the match count to provide a better specific left
match resolution.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:02 -08:00
John Johansen 73f488cd90 apparmor: convert attaching profiles via xattrs to use dfa matching
This converts profile attachment based on xattrs to a fixed extended
conditional using dfa matching.

This has a couple of advantages
- pattern matching can be used for the xattr match

- xattrs can be optional for an attachment or marked as required

- the xattr attachment conditional will be able to be combined with
  other extended conditionals when the flexible extended conditional
  work lands.

The xattr fixed extended conditional is appended to the xmatch
conditional. If an xattr attachment is specified the profile xmatch
will be generated regardless of whether there is a pattern match on
the executable name.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2018-02-09 11:30:02 -08:00
Matthew Garrett 8e51f9087f apparmor: Add support for attaching profiles via xattr, presence and value
Make it possible to tie Apparmor profiles to the presence of one or more
extended attributes, and optionally their values. An example usecase for
this is to automatically transition to a more privileged Apparmor profile
if an executable has a valid IMA signature, which can then be appraised
by the IMA subsystem.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:02 -08:00
John Johansen a0781209cb apparmor: cleanup: simplify code to get ns symlink name
ns_get_name() is called in only one place and can be folded in.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:02 -08:00
John Johansen cf91600071 apparmor: cleanup create_aafs() error path
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:02 -08:00
John Johansen d901d6a298 apparmor: dfa split verification of table headers
separate the different types of verification so they are logically
separate and can be reused separate of each other.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:02 -08:00
John Johansen 031dcc8f4e apparmor: dfa add support for state differential encoding
State differential encoding can provide better compression for
apparmor policy, without having significant impact on match time.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:01 -08:00
John Johansen 074c1cd798 apparmor: dfa move character match into a macro
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:01 -08:00
John Johansen 9fcf78cca1 apparmor: update domain transitions that are subsets of confinement at nnp
Domain transition so far have been largely blocked by no new privs,
unless the transition has been provably a subset of the previous
confinement. There was a couple problems with the previous
implementations,

- transitions that weren't explicitly a stack but resulted in a subset
  of confinement were disallowed

- confinement subsets were only calculated from the previous
  confinement instead of the confinement being enforced at the time of
  no new privs, so transitions would have to get progressively
  tighter.

Fix this by detecting and storing a reference to the task's
confinement at the "time" no new privs is set. This reference is then
used to determine whether a transition is a subsystem of the
confinement at the time no new privs was set.

Unfortunately the implementation is less than ideal in that we have to
detect no new privs after the fact when a task attempts a domain
transition. This is adequate for the currently but will not work in a
stacking situation where no new privs could be conceivably be set in
both the "host" and in the container.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-02-09 11:30:01 -08:00