Commit Graph

502 Commits

Author SHA1 Message Date
Xiu Jianfeng
6500eb3a48 apparmor: Fix memleak in aa_simple_write_to_buffer()
commit 417ea9fe972d2654a268ad66e89c8fcae67017c3 upstream.

When copy_from_user failed, the memory is freed by kvfree. however the
management struct and data blob are allocated independently, so only
kvfree(data) cause a memleak issue here. Use aa_put_loaddata(data) to
fix this issue.

Fixes: a6a52579e5 ("apparmor: split load data into management struct and data blob")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:15:36 +02:00
Xin Xiong
f4d5c77965 apparmor: fix reference count leak in aa_pivotroot()
commit 11c3627ec6b56c1525013f336f41b79a983b4d46 upstream.

The aa_pivotroot() function has a reference counting bug in a specific
path. When aa_replace_current_label() returns on success, the function
forgets to decrement the reference count of “target”, which is
increased earlier by build_pivotroot(), causing a reference leak.

Fix it by decreasing the refcount of “target” in that path.

Fixes: 2ea3ffb778 ("apparmor: add mount mediation")
Co-developed-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Co-developed-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Xin Xiong <xiongx18@fudan.edu.cn>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:15:36 +02:00
John Johansen
7af3595140 apparmor: fix overlapping attachment computation
commit 2504db207146543736e877241f3b3de005cbe056 upstream.

When finding the profile via patterned attachments, the longest left
match is being set to the static compile time value and not using the
runtime computed value.

Fix this by setting the candidate value to the greater of the
precomputed value or runtime computed value.

Fixes: 21f6066105 ("apparmor: improve overlapping domain attachment resolution")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:15:36 +02:00
Tom Rix
5fc2dbf79d apparmor: fix aa_label_asxprint return check
commit 3e2a3a0830a2090e766d0d887d52c67de2a6f323 upstream.

Clang static analysis reports this issue
label.c:1802:3: warning: 2nd function call argument
  is an uninitialized value
  pr_info("%s", str);
  ^~~~~~~~~~~~~~~~~~

str is set from a successful call to aa_label_asxprint(&str, ...)
On failure a negative value is returned, not a -1.  So change
the check.

Fixes: f1bd904175 ("apparmor: add the base fns() for domain labels")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:15:36 +02:00
John Johansen
36f846a842 apparmor: Fix failed mount permission check error message
commit ec240b5905bbb09a03dccffee03062cf39e38dc2 upstream.

When the mount check fails due to a permission check failure instead
of explicitly at one of the subcomponent checks, AppArmor is reporting
a failure in the flags match. However this is not true and AppArmor
can not attribute the error at this point to any particular component,
and should only indicate the mount failed due to missing permissions.

Fixes: 2ea3ffb778 ("apparmor: add mount mediation")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:15:35 +02:00
John Johansen
f6115835c6 apparmor: fix absroot causing audited secids to begin with =
commit 511f7b5b835726e844a5fc7444c18e4b8672edfd upstream.

AppArmor is prefixing secids that are converted to secctx with the =
to indicate the secctx should only be parsed from an absolute root
POV. This allows catching errors where secctx are reparsed back into
internal labels.

Unfortunately because audit is using secid to secctx conversion this
means that subject and object labels can result in a very unfortunate
== that can break audit parsing.

eg. the subj==unconfined term in the below audit message

type=USER_LOGIN msg=audit(1639443365.233:160): pid=1633 uid=0 auid=1000
ses=3 subj==unconfined msg='op=login id=1000 exe="/usr/sbin/sshd"
hostname=192.168.122.1 addr=192.168.122.1 terminal=/dev/pts/1 res=success'

Fix this by switch the prepending of = to a _. This still works as a
special character to flag this case without breaking audit. Also move
this check behind debug as it should not be needed during normal
operqation.

Fixes: 26b7899510 ("apparmor: add support for absolute root view based labels")
Reported-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:15:35 +02:00
John Johansen
2b426e32c8 apparmor: fix quiet_denied for file rules
commit 68ff8540cc9e4ab557065b3f635c1ff4c96e1f1c upstream.

Global quieting of denied AppArmor generated file events is not
handled correctly. Unfortunately the is checking if quieting of all
audit events is set instead of just denied events.

Fixes: 67012e8209 ("AppArmor: basic auditing infrastructure.")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:15:35 +02:00
Tom Rix
9f3eb0a8a5 apparmor: fix error check
[ Upstream commit d108370c644b153382632b3e5511ade575c91c86 ]

clang static analysis reports this representative problem:

label.c:1463:16: warning: Assigned value is garbage or undefined
        label->hname = name;
                     ^ ~~~~

In aa_update_label_name(), this the problem block of code

	if (aa_label_acntsxprint(&name, ...) == -1)
		return res;

On failure, aa_label_acntsxprint() has a more complicated return
that just -1.  So check for a negative return.

It was also noted that the aa_label_acntsxprint() main comment refers
to a nonexistent parameter, so clean up the comment.

Fixes: f1bd904175 ("apparmor: add the base fns() for domain labels")
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-26 11:36:14 +01:00
Andy Shevchenko
b0008fbdc7 apparmor: remove duplicate macro list_entry_is_head()
commit 9801ca279ad37f72f71234fa81722afd95a3f997 upstream.

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 <andriy.shevchenko@linux.intel.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E . Hallyn " <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nobuhiro Iwamatsu (CIP) <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-26 13:39:47 +02:00
John Johansen
fe1219a289 apparmor: ensure that dfa state tables have entries
commit c27c6bd2c4d6b6bb779f9b722d5607993e1d5e5c upstream.

Currently it is possible to specify a state machine table with 0 length,
this is not valid as optional tables are specified by not defining
the table as present. Further this allows by-passing the base tables
range check against the next/check tables.

Fixes: d901d6a298 ("apparmor: dfa split verification of table headers")
Reported-by: Mike Salvatore <mike.salvatore@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-22 09:32:06 +02:00
Jann Horn
3f9a54ce49 apparmor: don't try to replace stale label in ptraceme check
[ Upstream commit ca3fde5214e1d24f78269b337d3f22afd6bf445e ]

begin_current_label_crit_section() must run in sleepable context because
when label_is_stale() is true, aa_replace_current_label() runs, which uses
prepare_creds(), which can sleep.

Until now, the ptraceme access check (which runs with tasklist_lock held)
violated this rule.

Fixes: b2d09ae449 ("apparmor: move ptrace checks to using labels")
Reported-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 23:17:03 -04:00
John Johansen
3cc2aec68e apparmor: fix nnp subset test for unconfined
[ Upstream commit 3ed4aaa94fc07db3cd0c91be95e3e1b9782a2710 ]

The subset test is not taking into account the unconfined exception
which will cause profile transitions in the stacked confinement
case to fail when no_new_privs is applied.

This fixes a regression introduced in the fix for
https://bugs.launchpad.net/bugs/1839037

BugLink: https://bugs.launchpad.net/bugs/1844186
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25 15:32:52 +02:00
Mauricio Faria de Oliveira
70fa599235 apparmor: check/put label on apparmor_sk_clone_security()
[ Upstream commit 3b646abc5bc6c0df649daea4c2c976bd4d47e4c8 ]

Currently apparmor_sk_clone_security() does not check for existing
label/peer in the 'new' struct sock; it just overwrites it, if any
(with another reference to the label of the source sock.)

    static void apparmor_sk_clone_security(const struct sock *sk,
                                           struct sock *newsk)
    {
            struct aa_sk_ctx *ctx = SK_CTX(sk);
            struct aa_sk_ctx *new = SK_CTX(newsk);

            new->label = aa_get_label(ctx->label);
            new->peer = aa_get_label(ctx->peer);
    }

This might leak label references, which might overflow under load.
Thus, check for and put labels, to prevent such errors.

Note this is similarly done on:

    static int apparmor_socket_post_create(struct socket *sock, ...)
    ...
            if (sock->sk) {
                    struct aa_sk_ctx *ctx = SK_CTX(sock->sk);

                    aa_put_label(ctx->label);
                    ctx->label = aa_get_label(label);
            }
    ...

Context:
-------

The label reference count leak is observed if apparmor_sock_graft()
is called previously: this sets the 'ctx->label' field by getting
a reference to the current label (later overwritten, without put.)

    static void apparmor_sock_graft(struct sock *sk, ...)
    {
            struct aa_sk_ctx *ctx = SK_CTX(sk);

            if (!ctx->label)
                    ctx->label = aa_get_current_label();
    }

And that is the case on crypto/af_alg.c:af_alg_accept():

    int af_alg_accept(struct sock *sk, struct socket *newsock, ...)
    ...
            struct sock *sk2;
            ...
            sk2 = sk_alloc(...);
            ...
            security_sock_graft(sk2, newsock);
            security_sk_clone(sk, sk2);
    ...

Apparently both calls are done on their own right, especially for
other LSMs, being introduced in 2010/2014, before apparmor socket
mediation in 2017 (see commits [1,2,3,4]).

So, it looks OK there! Let's fix the reference leak in apparmor.

Test-case:
---------

Exercise that code path enough to overflow label reference count.

    $ cat aa-refcnt-af_alg.c
    #include <stdio.h>
    #include <string.h>
    #include <unistd.h>
    #include <sys/socket.h>
    #include <linux/if_alg.h>

    int main() {
            int sockfd;
            struct sockaddr_alg sa;

            /* Setup the crypto API socket */
            sockfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
            if (sockfd < 0) {
                    perror("socket");
                    return 1;
            }

            memset(&sa, 0, sizeof(sa));
            sa.salg_family = AF_ALG;
            strcpy((char *) sa.salg_type, "rng");
            strcpy((char *) sa.salg_name, "stdrng");

            if (bind(sockfd, (struct sockaddr *) &sa, sizeof(sa)) < 0) {
                    perror("bind");
                    return 1;
            }

            /* Accept a "connection" and close it; repeat. */
            while (!close(accept(sockfd, NULL, 0)));

            return 0;
    }

    $ gcc -o aa-refcnt-af_alg aa-refcnt-af_alg.c

    $ ./aa-refcnt-af_alg
    <a few hours later>

    [ 9928.475953] refcount_t overflow at apparmor_sk_clone_security+0x37/0x70 in aa-refcnt-af_alg[1322], uid/euid: 1000/1000
    ...
    [ 9928.507443] RIP: 0010:apparmor_sk_clone_security+0x37/0x70
    ...
    [ 9928.514286]  security_sk_clone+0x33/0x50
    [ 9928.514807]  af_alg_accept+0x81/0x1c0 [af_alg]
    [ 9928.516091]  alg_accept+0x15/0x20 [af_alg]
    [ 9928.516682]  SYSC_accept4+0xff/0x210
    [ 9928.519609]  SyS_accept+0x10/0x20
    [ 9928.520190]  do_syscall_64+0x73/0x130
    [ 9928.520808]  entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Note that other messages may be seen, not just overflow, depending on
the value being incremented by kref_get(); on another run:

    [ 7273.182666] refcount_t: saturated; leaking memory.
    ...
    [ 7273.185789] refcount_t: underflow; use-after-free.

Kprobes:
-------

Using kprobe events to monitor sk -> sk_security -> label -> count (kref):

Original v5.7 (one reference leak every iteration)

 ... (af_alg_accept+0x0/0x1c0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd2
 ... (af_alg_release_parent+0x0/0xd0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd4
 ... (af_alg_accept+0x0/0x1c0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd3
 ... (af_alg_release_parent+0x0/0xd0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd5
 ... (af_alg_accept+0x0/0x1c0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd4
 ... (af_alg_release_parent+0x0/0xd0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd6

Patched v5.7 (zero reference leak per iteration)

 ... (af_alg_accept+0x0/0x1c0) label=0xffff9ff376c25eb0 label_refcnt=0x593
 ... (af_alg_release_parent+0x0/0xd0) label=0xffff9ff376c25eb0 label_refcnt=0x594
 ... (af_alg_accept+0x0/0x1c0) label=0xffff9ff376c25eb0 label_refcnt=0x593
 ... (af_alg_release_parent+0x0/0xd0) label=0xffff9ff376c25eb0 label_refcnt=0x594
 ... (af_alg_accept+0x0/0x1c0) label=0xffff9ff376c25eb0 label_refcnt=0x593
 ... (af_alg_release_parent+0x0/0xd0) label=0xffff9ff376c25eb0 label_refcnt=0x594

Commits:
-------

[1] commit 507cad355f ("crypto: af_alg - Make sure sk_security is initialized on accept()ed sockets")
[2] commit 4c63f83c2c ("crypto: af_alg - properly label AF_ALG socket")
[3] commit 2acce6aa9f ("Networking") a.k.a ("crypto: af_alg - Avoid sock_graft call warning)
[4] commit 56974a6fcf ("apparmor: add base infastructure for socket mediation")

Fixes: 56974a6fcf ("apparmor: add base infastructure for socket mediation")
Reported-by: Brian Moyles <bmoyles@netflix.com>
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25 15:32:52 +02:00
John Johansen
86396a494e apparmor: fix introspection of of task mode for unconfined tasks
[ Upstream commit dd2569fbb053719f7df7ef8fdbb45cf47156a701 ]

Fix two issues with introspecting the task mode.

1. If a task is attached to a unconfined profile that is not the
   ns->unconfined profile then. Mode the mode is always reported
   as -

      $ ps -Z
      LABEL                               PID TTY          TIME CMD
      unconfined                         1287 pts/0    00:00:01 bash
      test (-)                           1892 pts/0    00:00:00 ps

   instead of the correct value of (unconfined) as shown below

      $ ps -Z
      LABEL                               PID TTY          TIME CMD
      unconfined                         2483 pts/0    00:00:01 bash
      test (unconfined)                  3591 pts/0    00:00:00 ps

2. if a task is confined by a stack of profiles that are unconfined
   the output of label mode is again the incorrect value of (-) like
   above, instead of (unconfined). This is because the visibile
   profile count increment is skipped by the special casing of
   unconfined.

Fixes: f1bd904175 ("apparmor: add the base fns() for domain labels")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25 15:32:51 +02:00
Xiyu Yang
c701849502 apparmor: Fix aa_label refcnt leak in policy_update
commit c6b39f070722ea9963ffe756bfe94e89218c5e63 upstream.

policy_update() invokes begin_current_label_crit_section(), which
returns a reference of the updated aa_label object to "label" with
increased refcount.

When policy_update() returns, "label" becomes invalid, so the refcount
should be decreased to keep refcount balanced.

The reference counting issue happens in one exception handling path of
policy_update(). When aa_may_manage_policy() returns not NULL, the
refcnt increased by begin_current_label_crit_section() is not decreased,
causing a refcnt leak.

Fix this issue by jumping to "end_section" label when
aa_may_manage_policy() returns not NULL.

Fixes: 5ac8c355ae ("apparmor: allow introspecting the loaded policy pre internal transform")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 17:37:37 +02:00
Xiyu Yang
dd73adb161 apparmor: fix potential label refcnt leak in aa_change_profile
commit a0b845ffa0d91855532b50fc040aeb2d8338dca4 upstream.

aa_change_profile() invokes aa_get_current_label(), which returns
a reference of the current task's label.

According to the comment of aa_get_current_label(), the returned
reference must be put with aa_put_label().
However, when the original object pointed by "label" becomes
unreachable because aa_change_profile() returns or a new object
is assigned to "label", reference count increased by
aa_get_current_label() is not decreased, causing a refcnt leak.

Fix this by calling aa_put_label() before aa_change_profile() return
and dropping unnecessary aa_get_current_label().

Fixes: 9fcf78cca1 ("apparmor: update domain transitions that are subsets of confinement at nnp")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 17:37:37 +02:00
Navid Emamdoost
f1738ae012 apparmor: Fix use-after-free in aa_audit_rule_init
commit c54d481d71c6849e044690d3960aaebc730224cc upstream.

In the implementation of aa_audit_rule_init(), when aa_label_parse()
fails the allocated memory for rule is released using
aa_audit_rule_free(). But after this release, the return statement
tries to access the label field of the rule which results in
use-after-free. Before releasing the rule, copy errNo and return it
after release.

Fixes: 52e8c38001 ("apparmor: Fix memory leak of rule on error exit path")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 17:37:37 +02:00
Jann Horn
e58f543fc7 apparmor: don't try to replace stale label in ptrace access check
[ Upstream commit 1f8266ff58840d698a1e96d2274189de1bdf7969 ]

As a comment above begin_current_label_crit_section() explains,
begin_current_label_crit_section() must run in sleepable context because
when label_is_stale() is true, aa_replace_current_label() runs, which uses
prepare_creds(), which can sleep.
Until now, the ptrace access check (which runs with a task lock held)
violated this rule.

Also add a might_sleep() assertion to begin_current_label_crit_section(),
because asserts are less likely to be ignored than comments.

Fixes: b2d09ae449 ("apparmor: move ptrace checks to using labels")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:49:55 +01:00
Tony Jones
451830a94b apparmor: Fix network performance issue in aa_label_sk_perm
[ Upstream commit 5f997580e8b12b9f585e34cc16304925d26ce49e ]

The netperf benchmark shows a 5.73% reduction in throughput for
small (64 byte) transfers by unconfined tasks.

DEFINE_AUDIT_SK() in aa_label_sk_perm() should not be performed
unconditionally, rather only when the label is confined.

netperf-tcp
                            56974a6fc^              56974a6fc
Min       64         563.48 (   0.00%)      531.17 (  -5.73%)
Min       128       1056.92 (   0.00%)      999.44 (  -5.44%)
Min       256       1945.95 (   0.00%)     1867.97 (  -4.01%)
Min       1024      6761.40 (   0.00%)     6364.23 (  -5.87%)
Min       2048     11110.53 (   0.00%)    10606.20 (  -4.54%)
Min       3312     13692.67 (   0.00%)    13158.41 (  -3.90%)
Min       4096     14926.29 (   0.00%)    14457.46 (  -3.14%)
Min       8192     18399.34 (   0.00%)    18091.65 (  -1.67%)
Min       16384    21384.13 (   0.00%)    21158.05 (  -1.06%)
Hmean     64         564.96 (   0.00%)      534.38 (  -5.41%)
Hmean     128       1064.42 (   0.00%)     1010.12 (  -5.10%)
Hmean     256       1965.85 (   0.00%)     1879.16 (  -4.41%)
Hmean     1024      6839.77 (   0.00%)     6478.70 (  -5.28%)
Hmean     2048     11154.80 (   0.00%)    10671.13 (  -4.34%)
Hmean     3312     13838.12 (   0.00%)    13249.01 (  -4.26%)
Hmean     4096     15009.99 (   0.00%)    14561.36 (  -2.99%)
Hmean     8192     18975.57 (   0.00%)    18326.54 (  -3.42%)
Hmean     16384    21440.44 (   0.00%)    21324.59 (  -0.54%)
Stddev    64           1.24 (   0.00%)        2.85 (-130.64%)
Stddev    128          4.51 (   0.00%)        6.53 ( -44.84%)
Stddev    256         11.67 (   0.00%)        8.50 (  27.16%)
Stddev    1024        48.33 (   0.00%)       75.07 ( -55.34%)
Stddev    2048        54.82 (   0.00%)       65.16 ( -18.86%)
Stddev    3312       153.57 (   0.00%)       56.29 (  63.35%)
Stddev    4096       100.25 (   0.00%)       88.50 (  11.72%)
Stddev    8192       358.13 (   0.00%)      169.99 (  52.54%)
Stddev    16384       43.99 (   0.00%)      141.82 (-222.39%)

Signed-off-by: Tony Jones <tonyj@suse.de>
Fixes: 56974a6fcf ("apparmor: add base infastructure for socket
mediation")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:49:54 +01:00
Micah Morton
87ca9aaf0c LSM: generalize flag passing to security_capable
[ Upstream commit c1a85a00ea66cb6f0bd0f14e47c28c2b0999799f ]

This patch provides a general mechanism for passing flags to the
security_capable LSM hook. It replaces the specific 'audit' flag that is
used to tell security_capable whether it should log an audit message for
the given capability check. The reason for generalizing this flag
passing is so we can add an additional flag that signifies whether
security_capable is being called by a setid syscall (which is needed by
the proposed SafeSetID LSM).

Signed-off-by: Micah Morton <mortonm@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-23 08:21:29 +01:00
John Johansen
f3248d6dce apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock
commit 8c62ed27a12c00e3db1c9f04bc0f272bdbb06734 upstream.

aa_xattrs_match() is unfortunately calling vfs_getxattr_alloc() from a
context protected by an rcu_read_lock. This can not be done as
vfs_getxattr_alloc() may sleep regardles of the gfp_t value being
passed to it.

Fix this by breaking the rcu_read_lock on the policy search when the
xattr match feature is requested and restarting the search if a policy
changes occur.

Fixes: 8e51f9087f ("apparmor: Add support for attaching profiles via xattr, presence and value")
Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09 10:19:02 +01:00
Colin Ian King
79a1eae9e4 apparmor: fix unsigned len comparison with less than zero
[ Upstream commit 00e0590dbaec6f1bcaa36a85467d7e3497ced522 ]

The sanity check in macro update_for_len checks to see if len
is less than zero, however, len is a size_t so it can never be
less than zero, so this sanity check is a no-op.  Fix this by
making len a ssize_t so the comparison will work and add ulen
that is a size_t copy of len so that the min() macro won't
throw warnings about comparing different types.

Addresses-Coverity: ("Macro compares unsigned to 0")
Fixes: f1bd904175 ("apparmor: add the base fns() for domain labels")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-04 19:13:08 +01:00
Chris Coulson
d8a89c3e75 apparmor: delete the dentry in aafs_remove() to avoid a leak
[ Upstream commit 201218e4d3dfa1346e30997f48725acce3f26d01 ]

Although the apparmorfs dentries are always dropped from the dentry cache
when the usage count drops to zero, there is no guarantee that this will
happen in aafs_remove(), as another thread might still be using it. In
this scenario, this means that the dentry will temporarily continue to
appear in the results of lookups, even after the call to aafs_remove().

In the case of removal of a profile - it also causes simple_rmdir()
on the profile directory to fail, as the directory won't be empty until
the usage counts of all child dentries have decreased to zero. This
results in the dentry for the profile directory leaking and appearing
empty in the file system tree forever.

Signed-off-by: Chris Coulson <chris.coulson@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-05 09:21:19 +01:00
Mike Salvatore
17111037fd apparmor: reset pos on failure to unpack for various functions
[ Upstream commit 156e42996bd84eccb6acf319f19ce0cb140d00e3 ]

Each function that manipulates the aa_ext struct should reset it's "pos"
member on failure. This ensures that, on failure, no changes are made to
the state of the aa_ext struct.

There are paths were elements are optional and the error path is
used to indicate the optional element is not present. This means
instead of just aborting on error the unpack stream can become
unsynchronized on optional elements, if using one of the affected
functions.

Cc: stable@vger.kernel.org
Fixes: 736ec752d9 ("AppArmor: policy routines for loading and unpacking policy")
Signed-off-by: Mike Salvatore <mike.salvatore@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-16 08:22:16 +02:00
Jann Horn
31c9958068 apparmor: enforce nullbyte at end of tag string
commit 8404d7a674c49278607d19726e0acc0cae299357 upstream.

A packed AppArmor policy contains null-terminated tag strings that are read
by unpack_nameX(). However, unpack_nameX() uses string functions on them
without ensuring that they are actually null-terminated, potentially
leading to out-of-bounds accesses.

Make sure that the tag string is null-terminated before passing it to
strcmp().

Cc: stable@vger.kernel.org
Fixes: 736ec752d9 ("AppArmor: policy routines for loading and unpacking policy")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-25 11:35:54 +08:00
John Johansen
eb2b0bf5c4 apparmor: fix PROFILE_MEDIATES for untrusted input
commit 23375b13f98c5464c2b4d15f983cc062940f1f4e upstream.

While commit 11c236b89d ("apparmor: add a default null dfa") ensure
every profile has a policy.dfa it does not resize the policy.start[]
to have entries for every possible start value. Which means
PROFILE_MEDIATES is not safe to use on untrusted input. Unforunately
commit b9590ad4c4 ("apparmor: remove POLICY_MEDIATES_SAFE") did not
take into account the start value usage.

The input string in profile_query_cb() is user controlled and is not
properly checked to be within the limited start[] entries, even worse
it can't be as userspace policy is allowed to make us of entries types
the kernel does not know about. This mean usespace can currently cause
the kernel to access memory up to 240 entries beyond the start array
bounds.

Cc: stable@vger.kernel.org
Fixes: b9590ad4c4 ("apparmor: remove POLICY_MEDIATES_SAFE")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-25 11:35:54 +08:00
Al Viro
b21ca2769b apparmorfs: fix use-after-free on symlink traversal
[ Upstream commit f51dcd0f621caac5380ce90fbbeafc32ce4517ae ]

symlink body shouldn't be freed without an RCU delay.  Switch apparmorfs
to ->destroy_inode() and use of call_rcu(); free both the inode and symlink
body in the callback.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-25 18:23:42 +02:00
John Johansen
d7807b6227 apparmor: Fix aa_label_build() error handling for failed merges
[ Upstream commit d6d478aee003e19ef90321176552a8ad2929a47f ]

aa_label_merge() can return NULL for memory allocations failures
make sure to handle and set the correct error in this case.

Reported-by: Peng Hao <peng.hao2@zte.com.cn>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:02:32 -07:00
Zubin Mithra
c8a1685aa3 apparmor: Fix uninitialized value in aa_split_fqname
[ Upstream commit 250f2da49cb8e582215a65c03f50e8ddf5cd119c ]

Syzkaller reported a OOB-read with the stacktrace below. This occurs
inside __aa_lookupn_ns as `n` is not initialized. `n` is obtained from
aa_splitn_fqname. In cases where `name` is invalid, aa_splitn_fqname
returns without initializing `ns_name` and `ns_len`.

Fix this by always initializing `ns_name` and `ns_len`.

	__dump_stack lib/dump_stack.c:77 [inline]
	dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113
	print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
	kasan_report_error mm/kasan/report.c:354 [inline]
	kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
	__asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
	memcmp+0xe3/0x160 lib/string.c:861
	strnstr+0x4b/0x70 lib/string.c:934
	__aa_lookupn_ns+0xc1/0x570 security/apparmor/policy_ns.c:209
	aa_lookupn_ns+0x88/0x1e0 security/apparmor/policy_ns.c:240
	aa_fqlookupn_profile+0x1b9/0x1010 security/apparmor/policy.c:468
	fqlookupn_profile+0x80/0xc0 security/apparmor/label.c:1844
	aa_label_strn_parse+0xa3a/0x1230 security/apparmor/label.c:1908
	aa_label_parse+0x42/0x50 security/apparmor/label.c:1943
	aa_change_profile+0x513/0x3510 security/apparmor/domain.c:1362
	apparmor_setprocattr+0xaa4/0x1150 security/apparmor/lsm.c:658
	security_setprocattr+0x66/0xc0 security/security.c:1298
	proc_pid_attr_write+0x301/0x540 fs/proc/base.c:2555
	__vfs_write+0x119/0x9f0 fs/read_write.c:485
	vfs_write+0x1fc/0x560 fs/read_write.c:549
	ksys_write+0x101/0x260 fs/read_write.c:598
	__do_sys_write fs/read_write.c:610 [inline]
	__se_sys_write fs/read_write.c:607 [inline]
	__x64_sys_write+0x73/0xb0 fs/read_write.c:607
	do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
	entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: 3b0aaf5866 ("apparmor: add lib fn to find the "split" for fqnames")
Reported-by: syzbot+61e4b490d9d2da591b50@syzkaller.appspotmail.com
Signed-off-by: Zubin Mithra <zsm@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-27 16:13:00 +01:00
John Johansen
edf4e7b7b9 apparmor: fix bad debug check in apparmor_secid_to_secctx()
apparmor_secid_to_secctx() has a bad debug statement tripping on a
condition handle by the code.  When kconfig SECURITY_APPARMOR_DEBUG is
enabled the debug WARN_ON will trip when **secdata is NULL resulting
in the following trace.

------------[ cut here ]------------
AppArmor WARN apparmor_secid_to_secctx: ((!secdata)):
WARNING: CPU: 0 PID: 14826 at security/apparmor/secid.c:82 apparmor_secid_to_secctx+0x2b5/0x2f0 security/apparmor/secid.c:82
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 14826 Comm: syz-executor1 Not tainted 4.19.0-rc1+ #193
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 panic+0x238/0x4e7 kernel/panic.c:184
 __warn.cold.8+0x163/0x1ba kernel/panic.c:536
 report_bug+0x252/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:993
RIP: 0010:apparmor_secid_to_secctx+0x2b5/0x2f0 security/apparmor/secid.c:82
Code: c7 c7 40 66 58 87 e8 6a 6d 0f fe 0f 0b e9 6c fe ff ff e8 3e aa 44 fe 48 c7 c6 80 67 58 87 48 c7 c7 a0 65 58 87 e8 4b 6d 0f fe <0f> 0b e9 3f fe ff ff 48 89 df e8 fc a7 83 fe e9 ed fe ff ff bb f4
RSP: 0018:ffff8801ba1bed10 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff8801ba1beed0 RCX: ffffc9000227e000
RDX: 0000000000018482 RSI: ffffffff8163ac01 RDI: 0000000000000001
RBP: ffff8801ba1bed30 R08: ffff8801b80ec080 R09: ffffed003b603eca
R10: ffffed003b603eca R11: ffff8801db01f657 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8801ba1beed0
 security_secid_to_secctx+0x63/0xc0 security/security.c:1314
 ctnetlink_secctx_size net/netfilter/nf_conntrack_netlink.c:621 [inline]
 ctnetlink_nlmsg_size net/netfilter/nf_conntrack_netlink.c:659 [inline]
 ctnetlink_conntrack_event+0x303/0x1470 net/netfilter/nf_conntrack_netlink.c:706
 nf_conntrack_eventmask_report+0x55f/0x930 net/netfilter/nf_conntrack_ecache.c:151
 nf_conntrack_event_report include/net/netfilter/nf_conntrack_ecache.h:112 [inline]
 nf_ct_delete+0x33c/0x5d0 net/netfilter/nf_conntrack_core.c:601
 nf_ct_iterate_cleanup+0x48c/0x5e0 net/netfilter/nf_conntrack_core.c:1892
 nf_ct_iterate_cleanup_net+0x23c/0x2d0 net/netfilter/nf_conntrack_core.c:1974
 ctnetlink_flush_conntrack net/netfilter/nf_conntrack_netlink.c:1226 [inline]
 ctnetlink_del_conntrack+0x66c/0x850 net/netfilter/nf_conntrack_netlink.c:1258
 nfnetlink_rcv_msg+0xd88/0x1070 net/netfilter/nfnetlink.c:228
 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2454
 nfnetlink_rcv+0x1c0/0x4d0 net/netfilter/nfnetlink.c:560
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:631
 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2114
 __sys_sendmsg+0x11d/0x290 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457089
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f7bc6e03c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f7bc6e046d4 RCX: 0000000000457089
RDX: 0000000000000000 RSI: 0000000020d65000 RDI: 0000000000000003
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d4588 R14: 00000000004c8d5c R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

CC: <stable@vger.kernel.org> #4.18
Fixes: c092921219 ("apparmor: add support for mapping secids and using secctxes")
Reported-by: syzbot+21016130b0580a9de3b5@syzkaller.appspotmail.com
Signed-off-by: John Johansen <john.johansen@canonical.com>
2018-09-03 11:15:29 -07:00
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 736ec752d9: "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