Of the three LSMs that implement the security_task_getsecid() LSM
hook, all three LSMs provide the task's objective security
credentials. This turns out to be unfortunate as most of the hook's
callers seem to expect the task's subjective credentials, although
a small handful of callers do correctly expect the objective
credentials.
This patch is the first step towards fixing the problem: it splits
the existing security_task_getsecid() hook into two variants, one
for the subjective creds, one for the objective creds.
void security_task_getsecid_subj(struct task_struct *p,
u32 *secid);
void security_task_getsecid_obj(struct task_struct *p,
u32 *secid);
While this patch does fix all of the callers to use the correct
variant, in order to keep this patch focused on the callers and to
ease review, the LSMs continue to use the same implementation for
both hooks. The net effect is that this patch should not change
the behavior of the kernel in any way, it will be up to the latter
LSM specific patches in this series to change the hook
implementations and return the correct credentials.
Acked-by: Mimi Zohar <zohar@linux.ibm.com> (IMA)
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
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>
Drop repeated words in comments.
{a, then, to}
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Delete the doubled word "then" in a comment.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
With LSM stacking calling back into capable to check for MAC_ADMIN
for apparmor policy results in asking the other stacked LSMs for
MAC_ADMIN resulting in the other LSMs answering based on their
policy management.
For apparmor policy management we just need to call apparmor's
capability fn directly.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Previously the policy capable checks assumed they were using the
current task. Make them take the task label so the query can be
made against an arbitrary task.
Signed-off-by: John Johansen <john.johansen@canonical.com>
The i_uid and i_gid are mostly used when logging for AppArmor. This is
broken in a bunch of places where the global root id is reported instead
of the i_uid or i_gid of the file. Nonetheless, be kind and log the
mapped inode if we're coming from an idmapped mount. If the initial user
namespace is passed nothing changes so non-idmapped mounts will see
identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-26-christian.brauner@ubuntu.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.
As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.
Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
When interacting with extended attributes the vfs verifies that the
caller is privileged over the inode with which the extended attribute is
associated. For posix access and posix default extended attributes a uid
or gid can be stored on-disk. Let the functions handle posix extended
attributes on idmapped mounts. If the inode is accessed through an
idmapped mount we need to map it according to the mount's user
namespace. Afterwards the checks are identical to non-idmapped mounts.
This has no effect for e.g. security xattrs since they don't store uids
or gids and don't perform permission checks on them like posix acls do.
Link: https://lore.kernel.org/r/20210121131959.646623-10-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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: e130816164 ("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>
A followup change to tcp_request_sock_op would have to drop the 'const'
qualifier from the 'route_req' function as the
'security_inet_conn_request' call is moved there - and that function
expects a 'struct sock *'.
However, it turns out its also possible to add a const qualifier to
security_inet_conn_request instead.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"A couple of minor documentation updates only for this release"
* tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
LSM: drop duplicated words in header file comments
Replace HTTP links with HTTPS ones: security
As said by Linus:
A symmetric naming is only helpful if it implies symmetries in use.
Otherwise it's actively misleading.
In "kzalloc()", the z is meaningful and an important part of what the
caller wants.
In "kzfree()", the z is actively detrimental, because maybe in the
future we really _might_ want to use that "memfill(0xdeadbeef)" or
something. The "zero" part of the interface isn't even _relevant_.
The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.
Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.
The renaming is done by using the command sequence:
git grep -w --name-only kzfree |\
xargs sed -i 's/kzfree/kfree_sensitive/'
followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.
[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
audit_log_string() was inteded to be an internal audit function and
since there are only two internal uses, remove them. Purge all external
uses of it by restructuring code to use an existing audit_log_format()
or using audit_log_format().
Please see the upstream issue
https://github.com/linux-audit/audit-kernel/issues/84
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This Kunit update for Linux 5.8-rc1 consists of:
- Several config fragment fixes from Anders Roxell to improve
test coverage.
- Improvements to kunit run script to use defconfig as default and
restructure the code for config/build/exec/parse from Vitor Massaru Iha
and David Gow.
- Miscellaneous documentation warn fix.
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Merge tag 'linux-kselftest-kunit-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kunit updates from Shuah Khan:
"This consists of:
- Several config fragment fixes from Anders Roxell to improve test
coverage.
- Improvements to kunit run script to use defconfig as default and
restructure the code for config/build/exec/parse from Vitor Massaru
Iha and David Gow.
- Miscellaneous documentation warn fix"
* tag 'linux-kselftest-kunit-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
security: apparmor: default KUNIT_* fragments to KUNIT_ALL_TESTS
fs: ext4: default KUNIT_* fragments to KUNIT_ALL_TESTS
drivers: base: default KUNIT_* fragments to KUNIT_ALL_TESTS
lib: Kconfig.debug: default KUNIT_* fragments to KUNIT_ALL_TESTS
kunit: default KUNIT_* fragments to KUNIT_ALL_TESTS
kunit: Kconfig: enable a KUNIT_ALL_TESTS fragment
kunit: Fix TabError, remove defconfig code and handle when there is no kunitconfig
kunit: use KUnit defconfig by default
kunit: use --build_dir=.kunit as default
Documentation: test.h - fix warnings
kunit: kunit_tool: Separate out config/build/exec/parse
+ Features
- Replace zero-length array with flexible-array
- add a valid state flags check
- add consistency check between state and dfa diff encode flags
- add apparmor subdir to proc attr interface
- fail unpack if profile mode is unknown
- add outofband transition and use it in xattr match
- ensure that dfa state tables have entries
+ Cleanups
- Use true and false for bool variable
- Remove semicolon
- Clean code by removing redundant instructions
- Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()
- remove duplicate check of xattrs on profile attachment
- remove useless aafs_create_symlink
+ Bug fixes
- Fix memory leak of profile proxy
- fix introspection of of task mode for unconfined tasks
- fix nnp subset test for unconfined
- check/put label on apparmor_sk_clone_security()
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Merge tag 'apparmor-pr-2020-06-07' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor
Pull apparmor updates from John Johansen:
"Features:
- Replace zero-length array with flexible-array
- add a valid state flags check
- add consistency check between state and dfa diff encode flags
- add apparmor subdir to proc attr interface
- fail unpack if profile mode is unknown
- add outofband transition and use it in xattr match
- ensure that dfa state tables have entries
Cleanups:
- Use true and false for bool variable
- Remove semicolon
- Clean code by removing redundant instructions
- Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()
- remove duplicate check of xattrs on profile attachment
- remove useless aafs_create_symlink
Bug fixes:
- Fix memory leak of profile proxy
- fix introspection of of task mode for unconfined tasks
- fix nnp subset test for unconfined
- check/put label on apparmor_sk_clone_security()"
* tag 'apparmor-pr-2020-06-07' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
apparmor: Fix memory leak of profile proxy
apparmor: fix introspection of of task mode for unconfined tasks
apparmor: check/put label on apparmor_sk_clone_security()
apparmor: Use true and false for bool variable
security/apparmor/label.c: Clean code by removing redundant instructions
apparmor: Replace zero-length array with flexible-array
apparmor: ensure that dfa state tables have entries
apparmor: remove duplicate check of xattrs on profile attachment.
apparmor: add outofband transition and use it in xattr match
apparmor: fail unpack if profile mode is unknown
apparmor: fix nnp subset test for unconfined
apparmor: remove useless aafs_create_symlink
apparmor: add proc subdir to attrs
apparmor: add consistency check between state and dfa diff encode flags
apparmor: add a valid state flags check
AppArmor: Remove semicolon
apparmor: Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()
When the proxy isn't replaced and the profile is removed, the proxy
is being leaked resulting in a kmemleak check message of
unreferenced object 0xffff888077a3a490 (size 16):
comm "apparmor_parser", pid 128041, jiffies 4322684109 (age 1097.028s)
hex dump (first 16 bytes):
03 00 00 00 00 00 00 00 b0 92 fd 4b 81 88 ff ff ...........K....
backtrace:
[<0000000084d5daf2>] aa_alloc_proxy+0x58/0xe0
[<00000000ecc0e21a>] aa_alloc_profile+0x159/0x1a0
[<000000004cc9ce15>] unpack_profile+0x275/0x1c40
[<000000007332b3ca>] aa_unpack+0x1e7/0x7e0
[<00000000e25e31bd>] aa_replace_profiles+0x18a/0x1d10
[<00000000350d9415>] policy_update+0x237/0x650
[<000000003fbf934e>] profile_load+0x122/0x160
[<0000000047f7b781>] vfs_write+0x139/0x290
[<000000008ad12358>] ksys_write+0xcd/0x170
[<000000001a9daa7b>] do_syscall_64+0x70/0x310
[<00000000b9efb0cf>] entry_SYSCALL_64_after_hwframe+0x49/0xb3
Make sure to cleanup the profile's embedded label which will result
on the proxy being properly freed.
Fixes: 637f688dc3 ("apparmor: switch from profiles to using labels on contexts")
Signed-off-by: John Johansen <john.johansen@canonical.com>
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>
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>
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.
Signed-off-by: John Johansen <john.johansen@canonical.com>
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")
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>
Pull execve updates from Eric Biederman:
"Last cycle for the Nth time I ran into bugs and quality of
implementation issues related to exec that could not be easily be
fixed because of the way exec is implemented. So I have been digging
into exec and cleanup up what I can.
I don't think I have exec sorted out enough to fix the issues I
started with but I have made some headway this cycle with 4 sets of
changes.
- promised cleanups after introducing exec_update_mutex
- trivial cleanups for exec
- control flow simplifications
- remove the recomputation of bprm->cred
The net result is code that is a bit easier to understand and work
with and a decrease in the number of lines of code (if you don't count
the added tests)"
* 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (24 commits)
exec: Compute file based creds only once
exec: Add a per bprm->file version of per_clear
binfmt_elf_fdpic: fix execfd build regression
selftests/exec: Add binfmt_script regression test
exec: Remove recursion from search_binary_handler
exec: Generic execfd support
exec/binfmt_script: Don't modify bprm->buf and then return -ENOEXEC
exec: Move the call of prepare_binprm into search_binary_handler
exec: Allow load_misc_binary to call prepare_binprm unconditionally
exec: Convert security_bprm_set_creds into security_bprm_repopulate_creds
exec: Factor security_bprm_creds_for_exec out of security_bprm_set_creds
exec: Teach prepare_exec_creds how exec treats uids & gids
exec: Set the point of no return sooner
exec: Move handling of the point of no return to the top level
exec: Run sync_mm_rss before taking exec_update_mutex
exec: Fix spelling of search_binary_handler in a comment
exec: Move the comment from above de_thread to above unshare_sighand
exec: Rename flush_old_exec begin_new_exec
exec: Move most of setup_new_exec into flush_old_exec
exec: In setup_new_exec cache current in the local variable me
...
This makes it easier to enable all KUnit fragments.
Adding 'if !KUNIT_ALL_TESTS' so individual tests can not be turned off.
Therefore if KUNIT_ALL_TESTS is enabled that will hide the prompt in
menuconfig.
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
The MSCC bug fix in 'net' had to be slightly adjusted because the
register accesses are done slightly differently in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
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>
Today security_bprm_set_creds has several implementations:
apparmor_bprm_set_creds, cap_bprm_set_creds, selinux_bprm_set_creds,
smack_bprm_set_creds, and tomoyo_bprm_set_creds.
Except for cap_bprm_set_creds they all test bprm->called_set_creds and
return immediately if it is true. The function cap_bprm_set_creds
ignores bprm->calld_sed_creds entirely.
Create a new LSM hook security_bprm_creds_for_exec that is called just
before prepare_binprm in __do_execve_file, resulting in a LSM hook
that is called exactly once for the entire of exec. Modify the bits
of security_bprm_set_creds that only want to be called once per exec
into security_bprm_creds_for_exec, leaving only cap_bprm_set_creds
behind.
Remove bprm->called_set_creds all of it's former users have been moved
to security_bprm_creds_for_exec.
Add or upate comments a appropriate to bring them up to date and
to reflect this change.
Link: https://lkml.kernel.org/r/87v9kszrzh.fsf_-_@x220.int.ebiederm.org
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Casey Schaufler <casey@schaufler-ca.com> # For the LSM and Smack bits
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Fixes coccicheck warnings:
security/apparmor/file.c:162:9-10: WARNING: return of 0/1 in function 'is_deleted' with return type bool
security/apparmor/file.c:362:9-10: WARNING: return of 0/1 in function 'xindex_is_subset' with return type bool
security/apparmor/policy_unpack.c:246:9-10: WARNING: return of 0/1 in function 'unpack_X' with return type bool
security/apparmor/policy_unpack.c:292:9-10: WARNING: return of 0/1 in function 'unpack_nameX' with return type bool
security/apparmor/policy_unpack.c:646:8-9: WARNING: return of 0/1 in function 'unpack_rlimits' with return type bool
security/apparmor/policy_unpack.c:604:8-9: WARNING: return of 0/1 in function 'unpack_secmark' with return type bool
security/apparmor/policy_unpack.c:538:8-9: WARNING: return of 0/1 in function 'unpack_trans_table' with return type bool
security/apparmor/policy_unpack.c:327:9-10: WARNING: return of 0/1 in function 'unpack_u32' with return type bool
security/apparmor/policy_unpack.c:345:9-10: WARNING: return of 0/1 in function 'unpack_u64' with return type bool
security/apparmor/policy_unpack.c:309:9-10: WARNING: return of 0/1 in function 'unpack_u8' with return type bool
security/apparmor/policy_unpack.c:568:8-9: WARNING: return of 0/1 in function 'unpack_xattrs' with return type bool
security/apparmor/policy_unpack.c:1007:10-11: WARNING: return of 0/1 in function 'verify_dfa_xindex' with return type bool
security/apparmor/policy_unpack.c:997:9-10: WARNING: return of 0/1 in function 'verify_xindex' with return type bool
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Previously 'label->proxy->label' value checking
and conditional reassigning were done twice in the same function.
The second one is redundant and can be removed.
Signed-off-by: Mateusz Nosek <mateusznosek0@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from userspace in common code. This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.
As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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>
Some .gitignore files have comments like "Generated files",
"Ignore generated files" at the header part, but they are
too obvious.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This kunit update for Linux 5.6-rc1 consists of:
-- Support for building kunit as a module from Alan Maguire
-- AppArmor KUnit tests for policy unpack from Mike Salvatore
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Merge tag 'linux-kselftest-5.6-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kselftest kunit updates from Shuah Khan:
"This kunit update consists of:
- Support for building kunit as a module from Alan Maguire
- AppArmor KUnit tests for policy unpack from Mike Salvatore"
* tag 'linux-kselftest-5.6-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
kunit: building kunit as a module breaks allmodconfig
kunit: update documentation to describe module-based build
kunit: allow kunit to be loaded as a module
kunit: remove timeout dependence on sysctl_hung_task_timeout_seconds
kunit: allow kunit tests to be loaded as a module
kunit: hide unexported try-catch interface in try-catch-impl.h
kunit: move string-stream.h to lib/kunit
apparmor: add AppArmor KUnit tests for policy unpack
Pull openat2 support from Al Viro:
"This is the openat2() series from Aleksa Sarai.
I'm afraid that the rest of namei stuff will have to wait - it got
zero review the last time I'd posted #work.namei, and there had been a
leak in the posted series I'd caught only last weekend. I was going to
repost it on Monday, but the window opened and the odds of getting any
review during that... Oh, well.
Anyway, openat2 part should be ready; that _did_ get sane amount of
review and public testing, so here it comes"
From Aleksa's description of the series:
"For a very long time, extending openat(2) with new features has been
incredibly frustrating. This stems from the fact that openat(2) is
possibly the most famous counter-example to the mantra "don't silently
accept garbage from userspace" -- it doesn't check whether unknown
flags are present[1].
This means that (generally) the addition of new flags to openat(2) has
been fraught with backwards-compatibility issues (O_TMPFILE has to be
defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
kernels gave errors, since it's insecure to silently ignore the
flag[2]). All new security-related flags therefore have a tough road
to being added to openat(2).
Furthermore, the need for some sort of control over VFS's path
resolution (to avoid malicious paths resulting in inadvertent
breakouts) has been a very long-standing desire of many userspace
applications.
This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset
(which was a variant of David Drysdale's O_BENEATH patchset[4] which
was a spin-off of the Capsicum project[5]) with a few additions and
changes made based on the previous discussion within [6] as well as
others I felt were useful.
In line with the conclusions of the original discussion of
AT_NO_JUMPS, the flag has been split up into separate flags. However,
instead of being an openat(2) flag it is provided through a new
syscall openat2(2) which provides several other improvements to the
openat(2) interface (see the patch description for more details). The
following new LOOKUP_* flags are added:
LOOKUP_NO_XDEV:
Blocks all mountpoint crossings (upwards, downwards, or through
absolute links). Absolute pathnames alone in openat(2) do not
trigger this. Magic-link traversal which implies a vfsmount jump is
also blocked (though magic-link jumps on the same vfsmount are
permitted).
LOOKUP_NO_MAGICLINKS:
Blocks resolution through /proc/$pid/fd-style links. This is done
by blocking the usage of nd_jump_link() during resolution in a
filesystem. The term "magic-links" is used to match with the only
reference to these links in Documentation/, but I'm happy to change
the name.
It should be noted that this is different to the scope of
~LOOKUP_FOLLOW in that it applies to all path components. However,
you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it
will *not* fail (assuming that no parent component was a
magic-link), and you will have an fd for the magic-link.
In order to correctly detect magic-links, the introduction of a new
LOOKUP_MAGICLINK_JUMPED state flag was required.
LOOKUP_BENEATH:
Disallows escapes to outside the starting dirfd's
tree, using techniques such as ".." or absolute links. Absolute
paths in openat(2) are also disallowed.
Conceptually this flag is to ensure you "stay below" a certain
point in the filesystem tree -- but this requires some additional
to protect against various races that would allow escape using
"..".
Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it
can trivially beam you around the filesystem (breaking the
protection). In future, there might be similar safety checks done
as in LOOKUP_IN_ROOT, but that requires more discussion.
In addition, two new flags are added that expand on the above ideas:
LOOKUP_NO_SYMLINKS:
Does what it says on the tin. No symlink resolution is allowed at
all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this
can still be used with NOFOLLOW to open an fd for the symlink as
long as no parent path had a symlink component.
LOOKUP_IN_ROOT:
This is an extension of LOOKUP_BENEATH that, rather than blocking
attempts to move past the root, forces all such movements to be
scoped to the starting point. This provides chroot(2)-like
protection but without the cost of a chroot(2) for each filesystem
operation, as well as being safe against race attacks that
chroot(2) is not.
If a race is detected (as with LOOKUP_BENEATH) then an error is
generated, and similar to LOOKUP_BENEATH it is not permitted to
cross magic-links with LOOKUP_IN_ROOT.
The primary need for this is from container runtimes, which
currently need to do symlink scoping in userspace[7] when opening
paths in a potentially malicious container.
There is a long list of CVEs that could have bene mitigated by
having RESOLVE_THIS_ROOT (such as CVE-2017-1002101,
CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a
few).
In order to make all of the above more usable, I'm working on
libpathrs[8] which is a C-friendly library for safe path resolution.
It features a userspace-emulated backend if the kernel doesn't support
openat2(2). Hopefully we can get userspace to switch to using it, and
thus get openat2(2) support for free once it's ready.
Future work would include implementing things like
RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow
programs to be sure they don't hit DoSes though stale NFS handles)"
* 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
Documentation: path-lookup: include new LOOKUP flags
selftests: add openat2(2) selftests
open: introduce openat2(2) syscall
namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution
namei: LOOKUP_IN_ROOT: chroot-like scoped resolution
namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution
namei: LOOKUP_NO_XDEV: block mountpoint crossing
namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution
namei: LOOKUP_NO_SYMLINKS: block symlink resolution
namei: allow set_root() to produce errors
namei: allow nd_jump_link() to produce errors
nsfs: clean-up ns_get_path() signature to return int
namei: only return -ECHILD from follow_dotdot_rcu()
The second check to ensure the xattrs are present and checked is
unneeded as this is already done in the profile attachment xmatch.
Signed-off-by: John Johansen <john.johansen@canonical.com>
There are cases where the a special out of band transition that can
not be triggered by input is useful in separating match conditions
in the dfa encoding.
The null_transition is currently used as an out of band transition
for match conditions that can not contain a \0 in their input
but apparmor needs an out of band transition for cases where
the match condition is allowed to contain any input character.
Achieve this by allowing for an explicit transition out of input
range that can only be triggered by code.
Signed-off-by: John Johansen <john.johansen@canonical.com>
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>
commit 1180b4c757 ("apparmor: fix dangling symlinks to policy
rawdata after replacement") reworked how the rawdata symlink is
handled but failedto remove aafs_create_symlink which was reduced to a
useles stub.
Fixes: 1180b4c757 ("apparmor: fix dangling symlinks to policy rawdata after replacement")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Check that a states diff encode flag is only set if diff encode is
enabled in the dfa header.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Two strings which did not contain a data format specification should be put
into a sequence. Thus use the corresponding function “seq_puts”.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: John Johansen <john.johansen@canonical.com>
kunit tests that do not support module build should depend
on KUNIT=y rather than just KUNIT in Kconfig, otherwise
they will trigger compilation errors for "make allmodconfig"
builds.
Fixes: 9fe124bf1b ("kunit: allow kunit to be loaded as a module")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Add KUnit tests to test AppArmor unpacking of userspace policies.
AppArmor uses a serialized binary format for loading policies. To find
policy format documentation see
Documentation/admin-guide/LSM/apparmor.rst.
In order to write the tests against the policy unpacking code, some
static functions needed to be exposed for testing purposes. One of the
goals of this patch is to establish a pattern for which testing these
kinds of functions should be done in the future.
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Mike Salvatore <mike.salvatore@canonical.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
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>
The common fast path check can be done under rcu_read_lock() and
doesn't need a reference count on the label. Only take a reference
count if entering the slow path.
Fixes reported hackbench regression
- sha1 79e178a57d ("Merge tag 'apparmor-pr-2019-12-03' of
git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor")
hackbench -l (256000/#grp) -g #grp
128 groups 19.679 ±0.90%
- previous sha1 01d1dff646 ("Merge tag 's390-5.5-2' of
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux")
hackbench -l (256000/#grp) -g #grp
128 groups 3.1689 ±3.04%
Reported-by: Vincent Guittot <vincent.guittot@linaro.org>
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Fixes: bce4e7e9c4 ("apparmor: reduce rcu_read_lock scope for aa_file_perm mediation")
Signed-off-by: John Johansen <john.johansen@canonical.com>
With commit df323337e5 ("apparmor: Use a memory pool instead per-CPU
caches, 2019-05-03"), AppArmor code was converted to use memory pools. In
that conversion, a bug snuck into the code that polices bind mounts that
causes all bind mounts to fail with -ENOMEM, as we erroneously error out
if `aa_get_buffer` returns a pointer instead of erroring out when it
does _not_ return a valid pointer.
Fix the issue by correctly checking for valid pointers returned by
`aa_get_buffer` to fix bind mounts with AppArmor.
Fixes: df323337e5 ("apparmor: Use a memory pool instead per-CPU caches")
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: John Johansen <john.johansen@canonical.com>
In preparation for LOOKUP_NO_MAGICLINKS, it's necessary to add the
ability for nd_jump_link() to return an error which the corresponding
get_link() caller must propogate back up to the VFS.
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
- increase left match history buffer size to provide inproved conflict
resolution in overlapping execution rules.
- switch buffer allocation to use a memory pool and GFP_KERNEL
where possible.
- add compression of policy blobs to reduce memory usage.
+ Cleanups
- fix spelling mistake "immutible" -> "immutable"
+ Bug fixes
- fix unsigned len comparison in update_for_len macro
- fix sparse warning for type-casting of current->real_cred
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Merge tag 'apparmor-pr-2019-12-03' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor
Pull apparmor updates from John Johansen:
"Features:
- increase left match history buffer size to provide improved
conflict resolution in overlapping execution rules.
- switch buffer allocation to use a memory pool and GFP_KERNEL where
possible.
- add compression of policy blobs to reduce memory usage.
Cleanups:
- fix spelling mistake "immutible" -> "immutable"
Bug fixes:
- fix unsigned len comparison in update_for_len macro
- fix sparse warning for type-casting of current->real_cred"
* tag 'apparmor-pr-2019-12-03' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
apparmor: make it so work buffers can be allocated from atomic context
apparmor: reduce rcu_read_lock scope for aa_file_perm mediation
apparmor: fix wrong buffer allocation in aa_new_mount
apparmor: fix unsigned len comparison with less than zero
apparmor: increase left match history buffer size
apparmor: Switch to GFP_KERNEL where possible
apparmor: Use a memory pool instead per-CPU caches
apparmor: Force type-casting of current->real_cred
apparmor: fix spelling mistake "immutible" -> "immutable"
apparmor: fix blob compression when ns is forced on a policy load
apparmor: fix missing ZLIB defines
apparmor: fix blob compression build failure on ppc
apparmor: Initial implementation of raw policy blob compression
In some situations AppArmor needs to be able to use its work buffers
from atomic context. Add the ability to specify when in atomic context
and hold a set of work buffers in reserve for atomic context to
reduce the chance that a large work buffer allocation will need to
be done.
Fixes: df323337e5 ("apparmor: Use a memory pool instead per-CPU caches")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Now that the buffers allocation has changed and no longer needs
the full mediation under an rcu_read_lock, reduce the rcu_read_lock
scope to only where it is necessary.
Fixes: df323337e5 ("apparmor: Use a memory pool instead per-CPU caches")
Signed-off-by: John Johansen <john.johansen@canonical.com>
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>
Pull vfs mount updates from Al Viro:
"The first part of mount updates.
Convert filesystems to use the new mount API"
* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
mnt_init(): call shmem_init() unconditionally
constify ksys_mount() string arguments
don't bother with registering rootfs
init_rootfs(): don't bother with init_ramfs_fs()
vfs: Convert smackfs to use the new mount API
vfs: Convert selinuxfs to use the new mount API
vfs: Convert securityfs to use the new mount API
vfs: Convert apparmorfs to use the new mount API
vfs: Convert openpromfs to use the new mount API
vfs: Convert xenfs to use the new mount API
vfs: Convert gadgetfs to use the new mount API
vfs: Convert oprofilefs to use the new mount API
vfs: Convert ibmasmfs to use the new mount API
vfs: Convert qib_fs/ipathfs to use the new mount API
vfs: Convert efivarfs to use the new mount API
vfs: Convert configfs to use the new mount API
vfs: Convert binfmt_misc to use the new mount API
convenience helper: get_tree_single()
convenience helper get_tree_nodev()
vfs: Kill sget_userns()
...
Pull locking updates from Ingo Molnar:
"The main changes in this cycle are:
- rwsem scalability improvements, phase #2, by Waiman Long, which are
rather impressive:
"On a 2-socket 40-core 80-thread Skylake system with 40 reader
and writer locking threads, the min/mean/max locking operations
done in a 5-second testing window before the patchset were:
40 readers, Iterations Min/Mean/Max = 1,807/1,808/1,810
40 writers, Iterations Min/Mean/Max = 1,807/50,344/151,255
After the patchset, they became:
40 readers, Iterations Min/Mean/Max = 30,057/31,359/32,741
40 writers, Iterations Min/Mean/Max = 94,466/95,845/97,098"
There's a lot of changes to the locking implementation that makes
it similar to qrwlock, including owner handoff for more fair
locking.
Another microbenchmark shows how across the spectrum the
improvements are:
"With a locking microbenchmark running on 5.1 based kernel, the
total locking rates (in kops/s) on a 2-socket Skylake system
with equal numbers of readers and writers (mixed) before and
after this patchset were:
# of Threads Before Patch After Patch
------------ ------------ -----------
2 2,618 4,193
4 1,202 3,726
8 802 3,622
16 729 3,359
32 319 2,826
64 102 2,744"
The changes are extensive and the patch-set has been through
several iterations addressing various locking workloads. There
might be more regressions, but unless they are pathological I
believe we want to use this new implementation as the baseline
going forward.
- jump-label optimizations by Daniel Bristot de Oliveira: the primary
motivation was to remove IPI disturbance of isolated RT-workload
CPUs, which resulted in the implementation of batched jump-label
updates. Beyond the improvement of the real-time characteristics
kernel, in one test this patchset improved static key update
overhead from 57 msecs to just 1.4 msecs - which is a nice speedup
as well.
- atomic64_t cross-arch type cleanups by Mark Rutland: over the last
~10 years of atomic64_t existence the various types used by the
APIs only had to be self-consistent within each architecture -
which means they became wildly inconsistent across architectures.
Mark puts and end to this by reworking all the atomic64
implementations to use 's64' as the base type for atomic64_t, and
to ensure that this type is consistently used for parameters and
return values in the API, avoiding further problems in this area.
- A large set of small improvements to lockdep by Yuyang Du: type
cleanups, output cleanups, function return type and othr cleanups
all around the place.
- A set of percpu ops cleanups and fixes by Peter Zijlstra.
- Misc other changes - please see the Git log for more details"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (82 commits)
locking/lockdep: increase size of counters for lockdep statistics
locking/atomics: Use sed(1) instead of non-standard head(1) option
locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING
x86/jump_label: Make tp_vec_nr static
x86/percpu: Optimize raw_cpu_xchg()
x86/percpu, sched/fair: Avoid local_clock()
x86/percpu, x86/irq: Relax {set,get}_irq_regs()
x86/percpu: Relax smp_processor_id()
x86/percpu: Differentiate this_cpu_{}() and __this_cpu_{}()
locking/rwsem: Guard against making count negative
locking/rwsem: Adaptive disabling of reader optimistic spinning
locking/rwsem: Enable time-based spinning on reader-owned rwsem
locking/rwsem: Make rwsem->owner an atomic_long_t
locking/rwsem: Enable readers spinning on writer
locking/rwsem: Clarify usage of owner's nonspinaable bit
locking/rwsem: Wake up almost all readers in wait queue
locking/rwsem: More optimal RT task handling of null owner
locking/rwsem: Always release wait_lock before waking up tasks
locking/rwsem: Implement lock handoff to prevent lock starvation
locking/rwsem: Make rwsem_spin_on_owner() return owner state
...
Convert the apparmorfs filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.
See Documentation/filesystems/mount_api.txt for more information.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: John Johansen <john.johansen@canonical.com>
cc: apparmor@lists.ubuntu.com
cc: linux-security-module@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
There have been cases reported where a history buffer size of 8 was
not enough to resolve conflict overlaps. Increase the buffer to and
get rid of the size element which is currently just storing the
constant WB_HISTORY_SIZE.
Signed-off-by: John Johansen <john.johansen@canonical.com>
After removing preempt_disable() from get_buffers() it is possible to
replace a few GFP_ATOMIC allocations with GFP_KERNEL.
Replace GFP_ATOMIC allocations with GFP_KERNEL where the context looks
to bee preepmtible.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The get_buffers() macro may provide one or two buffers to the caller.
Those buffers are pre-allocated on init for each CPU. By default it
allocates
2* 2 * MAX_PATH * POSSIBLE_CPU
which equals 64KiB on a system with 4 CPUs or 1MiB with 64 CPUs and so
on.
Replace the per-CPU buffers with a common memory pool which is shared
across all CPUs. The pool grows on demand and never shrinks. The pool
starts with two (UP) or four (SMP) elements. By using this pool it is
possible to request a buffer and keeping preemption enabled which avoids
the hack in profile_transition().
It has been pointed out by Tetsuo Handa that GFP_KERNEL allocations for
small amount of memory do not fail. In order not to have an endless
retry, __GFP_RETRY_MAYFAIL is passed (so the memory allocation is not
repeated until success) and retried once hoping that in the meantime a
buffer has been returned to the pool. Since now NULL is possible all
allocation paths check the buffer pointer and return -ENOMEM on failure.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>
This patch fixes the sparse warning:
warning: cast removes address space '<asn:4>' of expression.
Signed-off-by: Bharath Vedartham <linux.bhar@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
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>
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>
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>
All callers of lockdep_assert_held_exclusive() use it to verify the
correct locking state of either a semaphore (ldisc_sem in tty,
mmap_sem for perf events, i_rwsem of inode for dax) or rwlock by
apparmor. Thus it makes sense to rename _exclusive to _write since
that's the semantics callers care. Additionally there is already
lockdep_assert_held_read(), which this new naming is more consistent with.
No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190531100651.3969-1-nborisov@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 315 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull vfs inode freeing updates from Al Viro:
"Introduction of separate method for RCU-delayed part of
->destroy_inode() (if any).
Pretty much as posted, except that destroy_inode() stashes
->free_inode into the victim (anon-unioned with ->i_fops) before
scheduling i_callback() and the last two patches (sockfs conversion
and folding struct socket_wq into struct socket) are excluded - that
pair should go through netdev once davem reopens his tree"
* 'work.icache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (58 commits)
orangefs: make use of ->free_inode()
shmem: make use of ->free_inode()
hugetlb: make use of ->free_inode()
overlayfs: make use of ->free_inode()
jfs: switch to ->free_inode()
fuse: switch to ->free_inode()
ext4: make use of ->free_inode()
ecryptfs: make use of ->free_inode()
ceph: use ->free_inode()
btrfs: use ->free_inode()
afs: switch to use of ->free_inode()
dax: make use of ->free_inode()
ntfs: switch to ->free_inode()
securityfs: switch to ->free_inode()
apparmor: switch to ->free_inode()
rpcpipe: switch to ->free_inode()
bpf: switch to ->free_inode()
mqueue: switch to ->free_inode()
ufs: switch to ->free_inode()
coda: switch to ->free_inode()
...
Pull crypto update from Herbert Xu:
"API:
- Add support for AEAD in simd
- Add fuzz testing to testmgr
- Add panic_on_fail module parameter to testmgr
- Use per-CPU struct instead multiple variables in scompress
- Change verify API for akcipher
Algorithms:
- Convert x86 AEAD algorithms over to simd
- Forbid 2-key 3DES in FIPS mode
- Add EC-RDSA (GOST 34.10) algorithm
Drivers:
- Set output IV with ctr-aes in crypto4xx
- Set output IV in rockchip
- Fix potential length overflow with hashing in sun4i-ss
- Fix computation error with ctr in vmx
- Add SM4 protected keys support in ccree
- Remove long-broken mxc-scc driver
- Add rfc4106(gcm(aes)) cipher support in cavium/nitrox"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (179 commits)
crypto: ccree - use a proper le32 type for le32 val
crypto: ccree - remove set but not used variable 'du_size'
crypto: ccree - Make cc_sec_disable static
crypto: ccree - fix spelling mistake "protedcted" -> "protected"
crypto: caam/qi2 - generate hash keys in-place
crypto: caam/qi2 - fix DMA mapping of stack memory
crypto: caam/qi2 - fix zero-length buffer DMA mapping
crypto: stm32/cryp - update to return iv_out
crypto: stm32/cryp - remove request mutex protection
crypto: stm32/cryp - add weak key check for DES
crypto: atmel - remove set but not used variable 'alg_name'
crypto: picoxcell - Use dev_get_drvdata()
crypto: crypto4xx - get rid of redundant using_sd variable
crypto: crypto4xx - use sync skcipher for fallback
crypto: crypto4xx - fix cfb and ofb "overran dst buffer" issues
crypto: crypto4xx - fix ctr-aes missing output IV
crypto: ecrdsa - select ASN1 and OID_REGISTRY for EC-RDSA
crypto: ux500 - use ccflags-y instead of CFLAGS_<basename>.o
crypto: ccree - handle tee fips error during power management resume
crypto: ccree - add function to handle cryptocell tee fips error
...
Pull vfs fixes from Al Viro:
- a couple of ->i_link use-after-free fixes
- regression fix for wrong errno on absent device name in mount(2)
(this cycle stuff)
- ancient UFS braino in large GID handling on Solaris UFS images (bogus
cut'n'paste from large UID handling; wrong field checked to decide
whether we should look at old (16bit) or new (32bit) field)
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour
Abort file_remove_privs() for non-reg. files
[fix] get rid of checking for absent device name in vfs_get_tree()
apparmorfs: fix use-after-free on symlink traversal
securityfs: fix use-after-free on symlink traversal
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.
With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP. These would all need to be fixed if any shash algorithm
actually started sleeping. For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API. However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.
Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk. It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.
Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
There is a spelling mistake in an information message string, fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
When blob compression is turned on, if the policy namespace is forced
onto a policy load, the policy load will fail as the namespace name
being referenced is inside the compressed policy blob, resulting in
invalid or names that are too long. So duplicate the name before the
blob is compressed.
Fixes: 876dd866c084 ("apparmor: Initial implementation of raw policy blob compression")
Signed-off-by: John Johansen <john.johansen@canonical.com>
On configs where ZLIB is not already selected we are getting
undefined reference to `zlib_deflateInit2'
undefined reference to `zlib_deflate'
undefined reference to `zlib_deflateEnd'
For now just select the necessary ZLIB configs.
Fixes: 876dd866c084 ("apparmor: Initial implementation of raw policy blob compression")
Signed-off-by: John Johansen <john.johansen@canonical.com>
security/apparmor/policy_unpack.c: In function 'deflate_compress':
security/apparmor/policy_unpack.c:1064:4: error: implicit declaration of function 'vfree'; did you mean 'kfree'? [-Werror=implicit-function-declaration]
vfree(stgbuf);
^~~~~
kfree
Fixes: 876dd866c084 ("apparmor: Initial implementation of raw policy blob compression")
Signed-off-by: John Johansen <john.johansen@canonical.com>
This adds an initial implementation of raw policy blob compression,
using deflate. Compression level can be controlled via a new sysctl,
"apparmor.rawdata_compression_level", which can be set to a value
between 0 (no compression) and 9 (highest compression).
Signed-off-by: Chris Coulson <chris.coulson@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
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>
Before commit c5459b829b ("LSM: Plumb visibility into optional "enabled"
state"), /sys/module/apparmor/parameters/enabled would show "Y" or "N"
since it was using the "bool" handler. After being changed to "int",
this switched to "1" or "0", breaking the userspace AppArmor detection
of dbus-broker. This restores the Y/N output while keeping the LSM
infrastructure happy.
Before:
$ cat /sys/module/apparmor/parameters/enabled
1
After:
$ cat /sys/module/apparmor/parameters/enabled
Y
Reported-by: David Rheinsberg <david.rheinsberg@gmail.com>
Reviewed-by: David Rheinsberg <david.rheinsberg@gmail.com>
Link: https://lkml.kernel.org/r/CADyDSO6k8vYb1eryT4g6+EHrLCvb68GAbHVWuULkYjcZcYNhhw@mail.gmail.com
Fixes: c5459b829b ("LSM: Plumb visibility into optional "enabled" state")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>
- fix double when failing to unpack secmark rules in policy
- fix leak of dentry when profile is removed
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Merge tag 'apparmor-pr-2019-03-12' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor
Pull apparmor fixes from John Johansen:
- fix double when failing to unpack secmark rules in policy
- fix leak of dentry when profile is removed
* tag 'apparmor-pr-2019-03-12' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
apparmor: fix double free when unpack of secmark rules fails
apparmor: delete the dentry in aafs_remove() to avoid a leak
apparmor: Fix warning about unused function apparmor_ipv6_postroute
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>
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Merge tag 'audit-pr-20190305' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"A lucky 13 audit patches for v5.1.
Despite the rather large diffstat, most of the changes are from two
bug fix patches that move code from one Kconfig option to another.
Beyond that bit of churn, the remaining changes are largely cleanups
and bug-fixes as we slowly march towards container auditing. It isn't
all boring though, we do have a couple of new things: file
capabilities v3 support, and expanded support for filtering on
filesystems to solve problems with remote filesystems.
All changes pass the audit-testsuite. Please merge for v5.1"
* tag 'audit-pr-20190305' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: mark expected switch fall-through
audit: hide auditsc_get_stamp and audit_serial prototypes
audit: join tty records to their syscall
audit: remove audit_context when CONFIG_ AUDIT and not AUDITSYSCALL
audit: remove unused actx param from audit_rule_match
audit: ignore fcaps on umount
audit: clean up AUDITSYSCALL prototypes and stubs
audit: more filter PATH records keyed on filesystem magic
audit: add support for fcaps v3
audit: move loginuid and sessionid from CONFIG_AUDITSYSCALL to CONFIG_AUDIT
audit: add syscall information to CONFIG_CHANGE records
audit: hand taken context to audit_kill_trees for syscall logging
audit: give a clue what CONFIG_CHANGE op was involved
Pull security subsystem updates from James Morris:
- Extend LSM stacking to allow sharing of cred, file, ipc, inode, and
task blobs. This paves the way for more full-featured LSMs to be
merged, and is specifically aimed at LandLock and SARA LSMs. This
work is from Casey and Kees.
- There's a new LSM from Micah Morton: "SafeSetID gates the setid
family of syscalls to restrict UID/GID transitions from a given
UID/GID to only those approved by a system-wide whitelist." This
feature is currently shipping in ChromeOS.
* 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (62 commits)
keys: fix missing __user in KEYCTL_PKEY_QUERY
LSM: Update list of SECURITYFS users in Kconfig
LSM: Ignore "security=" when "lsm=" is specified
LSM: Update function documentation for cap_capable
security: mark expected switch fall-throughs and add a missing break
tomoyo: Bump version.
LSM: fix return value check in safesetid_init_securityfs()
LSM: SafeSetID: add selftest
LSM: SafeSetID: remove unused include
LSM: SafeSetID: 'depend' on CONFIG_SECURITY
LSM: Add 'name' field for SafeSetID in DEFINE_LSM
LSM: add SafeSetID module that gates setid calls
LSM: add SafeSetID module that gates setid calls
tomoyo: Allow multiple use_group lines.
tomoyo: Coding style fix.
tomoyo: Swicth from cred->security to task_struct->security.
security: keys: annotate implicit fall throughs
security: keys: annotate implicit fall throughs
security: keys: annotate implicit fall through
capabilities:: annotate implicit fall through
...
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.
This patch fixes the following warnings:
security/integrity/ima/ima_template_lib.c:85:10: warning: this statement may fall through [-Wimplicit-fallthrough=]
security/integrity/ima/ima_policy.c:940:18: warning: this statement may fall through [-Wimplicit-fallthrough=]
security/integrity/ima/ima_policy.c:943:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
security/integrity/ima/ima_policy.c:972:21: warning: this statement may fall through [-Wimplicit-fallthrough=]
security/integrity/ima/ima_policy.c:974:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
security/smack/smack_lsm.c:3391:9: warning: this statement may fall through [-Wimplicit-fallthrough=]
security/apparmor/domain.c:569:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
Warning level 3 was used: -Wimplicit-fallthrough=3
Also, add a missing break statement to fix the following warning:
security/integrity/ima/ima_appraise.c:116:26: warning: this statement may fall through [-Wimplicit-fallthrough=]
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
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>
when compiled without CONFIG_IPV6:
security/apparmor/lsm.c:1601:21: warning: ‘apparmor_ipv6_postroute’ defined but not used [-Wunused-function]
static unsigned int apparmor_ipv6_postroute(void *priv,
^~~~~~~~~~~~~~~~~~~~~~~
Reported-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Tested-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The audit_rule_match() struct audit_context *actx parameter is not used
by any in-tree consumers (selinux, apparmour, integrity, smack).
The audit context is an internal audit structure that should only be
accessed by audit accessor functions.
It was part of commit 03d37d25e0 ("LSM/Audit: Introduce generic
Audit LSM hooks") but appears to have never been used.
Remove it.
Please see the github issue
https://github.com/linux-audit/audit-kernel/issues/107
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: fixed the referenced commit title]
Signed-off-by: Paul Moore <paul@paul-moore.com>
AppArmor will no longer be the only user of task blob
after TOMOYO started using task blob.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: f4ad8f2c40 ("LSM: Infrastructure management of the task security")
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.morris@microsoft.com>
Since current->cred == current->real_cred when ordered_lsm_init()
is called, and lsm_early_cred()/lsm_early_task() need to be called
between the amount of required bytes is determined and module specific
initialization function is called, we can move these calls from
individual modules to ordered_lsm_init().
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
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>
Move management of the task_struct->security blob out
of the individual security modules and into the security
infrastructure. Instead of allocating the blobs from within
the modules the modules tell the infrastructure how much
space is required, and the space is allocated there.
The only user of this blob is AppArmor. The AppArmor use
is abstracted to avoid future conflict.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[kees: adjusted for ordered init series]
Signed-off-by: Kees Cook <keescook@chromium.org>
Move management of the file->f_security blob out of the
individual security modules and into the infrastructure.
The modules no longer allocate or free the data, instead
they tell the infrastructure how much space they require.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[kees: adjusted for ordered init series]
Signed-off-by: Kees Cook <keescook@chromium.org>
Move management of the cred security blob out of the
security modules and into the security infrastructre.
Instead of allocating and freeing space the security
modules tell the infrastructure how much space they
require.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[kees: adjusted for ordered init series]
Signed-off-by: Kees Cook <keescook@chromium.org>
Al Viro