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4627 commits

Author SHA1 Message Date
Eric W. Biederman
e32f887901 Merge commit a4ae32c71f ("exec: Always set cap_ambient in cap_bprm_set_creds")
This is a bug fix and one of two places where I have found that the
result of calling security_bprm_repopulate_creds more than once on
different bprm->files depends on all of the bprm->files not just the
file bprm->file.

I intend to fix both of those cases and then modify the code to
only call security_bprm_repopulate_creds on the final bprm file.

So merge this change in so I hopefully reduce conflicts for others
and I make it possible to build on top of this change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-05-27 22:37:33 -05:00
Linus Torvalds
3301f6ae2d Merge branch 'for-5.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:

 - Reverted stricter synchronization for cgroup recursive stats which
   was prepping it for event counter usage which never got merged. The
   change was causing performation regressions in some cases.

 - Restore bpf-based device-cgroup operation even when cgroup1 device
   cgroup is disabled.

 - An out-param init fix.

* 'for-5.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  device_cgroup: Cleanup cgroup eBPF device filter code
  xattr: fix uninitialized out-param
  Revert "cgroup: Add memory barriers to plug cgroup_rstat_updated() race window"
2020-05-27 10:58:19 -07:00
Linus Torvalds
006f38a1c3 Merge branch 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull execve fix from Eric Biederman:
 "While working on my exec cleanups I found a bug in exec that winds up
  miscomputing the ambient credentials during exec. Andy appears to have
  to been confused as to why credentials are computed for both the
  script and the interpreter

  From the original patch description:

   [3] Linux very confusingly processes both the script and the
       interpreter if applicable, for reasons that elude me. The results
       from thinking about a script's file capabilities and/or setuid
       bits are mostly discarded.

  The only value in struct cred that gets changed in cap_bprm_set_creds
  that I could find that might persist between the script and the
  interpreter was cap_ambient. Which is fixed with this trivial change"

* 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  exec: Always set cap_ambient in cap_bprm_set_creds
2020-05-27 09:53:25 -07:00
Eric W. Biederman
a4ae32c71f exec: Always set cap_ambient in cap_bprm_set_creds
An invariant of cap_bprm_set_creds is that every field in the new cred
structure that cap_bprm_set_creds might set, needs to be set every
time to ensure the fields does not get a stale value.

The field cap_ambient is not set every time cap_bprm_set_creds is
called, which means that if there is a suid or sgid script with an
interpreter that has neither the suid nor the sgid bits set the
interpreter should be able to accept ambient credentials.
Unfortuantely because cap_ambient is not reset to it's original value
the interpreter can not accept ambient credentials.

Given that the ambient capability set is expected to be controlled by
the caller, I don't think this is particularly serious.  But it is
definitely worth fixing so the code works correctly.

I have tested to verify my reading of the code is correct and the
interpreter of a sgid can receive ambient capabilities with this
change and cannot receive ambient capabilities without this change.

Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@kernel.org>
Fixes: 58319057b7 ("capabilities: ambient capabilities")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-05-26 13:11:00 -05:00
David S. Miller
13209a8f73 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
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>
2020-05-24 13:47:27 -07:00
Linus Torvalds
caffb99b69 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Fix RCU warnings in ipv6 multicast router code, from Madhuparna
    Bhowmik.

 2) Nexthop attributes aren't being checked properly because of
    mis-initialized iterator, from David Ahern.

 3) Revert iop_idents_reserve() change as it caused performance
    regressions and was just working around what is really a UBSAN bug
    in the compiler. From Yuqi Jin.

 4) Read MAC address properly from ROM in bmac driver (double iteration
    proceeds past end of address array), from Jeremy Kerr.

 5) Add Microsoft Surface device IDs to r8152, from Marc Payne.

 6) Prevent reference to freed SKB in __netif_receive_skb_core(), from
    Boris Sukholitko.

 7) Fix ACK discard behavior in rxrpc, from David Howells.

 8) Preserve flow hash across packet scrubbing in wireguard, from Jason
    A. Donenfeld.

 9) Cap option length properly for SO_BINDTODEVICE in AX25, from Eric
    Dumazet.

10) Fix encryption error checking in kTLS code, from Vadim Fedorenko.

11) Missing BPF prog ref release in flow dissector, from Jakub Sitnicki.

12) dst_cache must be used with BH disabled in tipc, from Eric Dumazet.

13) Fix use after free in mlxsw driver, from Jiri Pirko.

14) Order kTLS key destruction properly in mlx5 driver, from Tariq
    Toukan.

15) Check devm_platform_ioremap_resource() return value properly in
    several drivers, from Tiezhu Yang.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (71 commits)
  net: smsc911x: Fix runtime PM imbalance on error
  net/mlx4_core: fix a memory leak bug.
  net: ethernet: ti: cpsw: fix ASSERT_RTNL() warning during suspend
  net: phy: mscc: fix initialization of the MACsec protocol mode
  net: stmmac: don't attach interface until resume finishes
  net: Fix return value about devm_platform_ioremap_resource()
  net/mlx5: Fix error flow in case of function_setup failure
  net/mlx5e: CT: Correctly get flow rule
  net/mlx5e: Update netdev txq on completions during closure
  net/mlx5: Annotate mutex destroy for root ns
  net/mlx5: Don't maintain a case of del_sw_func being null
  net/mlx5: Fix cleaning unmanaged flow tables
  net/mlx5: Fix memory leak in mlx5_events_init
  net/mlx5e: Fix inner tirs handling
  net/mlx5e: kTLS, Destroy key object after destroying the TIS
  net/mlx5e: Fix allowed tc redirect merged eswitch offload cases
  net/mlx5: Avoid processing commands before cmdif is ready
  net/mlx5: Fix a race when moving command interface to events mode
  net/mlx5: Add command entry handling completion
  rxrpc: Fix a memory leak in rxkad_verify_response()
  ...
2020-05-23 17:16:18 -07:00
Mimi Zohar
8eb613c0b8 ima: verify mprotect change is consistent with mmap policy
Files can be mmap'ed read/write and later changed to execute to circumvent
IMA's mmap appraise policy rules.  Due to locking issues (mmap semaphore
would be taken prior to i_mutex), files can not be measured or appraised at
this point.  Eliminate this integrity gap, by denying the mprotect
PROT_EXECUTE change, if an mmap appraise policy rule exists.

On mprotect change success, return 0.  On failure, return -EACESS.

Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-22 14:41:04 -04:00
Navid Emamdoost
c54d481d71 apparmor: Fix use-after-free in aa_audit_rule_init
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>
2020-05-21 15:25:51 -07:00
Xiyu Yang
c6b39f0707 apparmor: Fix aa_label refcnt leak in policy_update
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>
2020-05-21 15:25:51 -07:00
Xiyu Yang
a0b845ffa0 apparmor: fix potential label refcnt leak in aa_change_profile
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>
2020-05-21 15:25:51 -07:00
Eric W. Biederman
112b714759 exec: Convert security_bprm_set_creds into security_bprm_repopulate_creds
Rename bprm->cap_elevated to bprm->active_secureexec and initialize it
in prepare_binprm instead of in cap_bprm_set_creds.  Initializing
bprm->active_secureexec in prepare_binprm allows multiple
implementations of security_bprm_repopulate_creds to play nicely with
each other.

Rename security_bprm_set_creds to security_bprm_reopulate_creds to
emphasize that this path recomputes part of bprm->cred.  This
recomputation avoids the time of check vs time of use problems that
are inherent in unix #! interpreters.

In short two renames and a move in the location of initializing
bprm->active_secureexec.

Link: https://lkml.kernel.org/r/87o8qkzrxp.fsf_-_@x220.int.ebiederm.org
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-05-21 10:16:50 -05:00
KP Singh
0550cfe8c2 security: Fix hook iteration for secid_to_secctx
secid_to_secctx is not stackable, and since the BPF LSM registers this
hook by default, the call_int_hook logic is not suitable which
"bails-on-fail" and casues issues when other LSMs register this hook and
eventually breaks Audit.

In order to fix this, directly iterate over the security hooks instead
of using call_int_hook as suggested in:

https: //lore.kernel.org/bpf/9d0eb6c6-803a-ff3a-5603-9ad6d9edfc00@schaufler-ca.com/#t

Fixes: 98e828a065 ("security: Refactor declaration of LSM hooks")
Fixes: 625236ba38 ("security: Fix the default value of secid_to_secctx hook")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200520125616.193765-1-kpsingh@chromium.org
2020-05-20 20:12:07 -07:00
Eric W. Biederman
b8bff59926 exec: Factor security_bprm_creds_for_exec out of security_bprm_set_creds
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>
2020-05-20 14:45:31 -05:00
David Howells
a8478a6029 smack: Implement the watch_key and post_notification hooks
Implement the watch_key security hook in Smack to make sure that a key
grants the caller Read permission in order to set a watch on a key.

Also implement the post_notification security hook to make sure that the
notification source is granted Write permission by the watch queue.

For the moment, the watch_devices security hook is left unimplemented as
it's not obvious what the object should be since the queue is global and
didn't previously exist.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2020-05-19 15:47:38 +01:00
David Howells
3e412ccc22 selinux: Implement the watch_key security hook
Implement the watch_key security hook to make sure that a key grants the
caller View permission in order to set a watch on a key.

For the moment, the watch_devices security hook is left unimplemented as
it's not obvious what the object should be since the queue is global and
didn't previously exist.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
2020-05-19 15:47:15 +01:00
David Howells
8c0637e950 keys: Make the KEY_NEED_* perms an enum rather than a mask
Since the meaning of combining the KEY_NEED_* constants is undefined, make
it so that you can't do that by turning them into an enum.

The enum is also given some extra values to represent special
circumstances, such as:

 (1) The '0' value is reserved and causes a warning to trap the parameter
     being unset.

 (2) The key is to be unlinked and we require no permissions on it, only
     the keyring, (this replaces the KEY_LOOKUP_FOR_UNLINK flag).

 (3) An override due to CAP_SYS_ADMIN.

 (4) An override due to an instantiation token being present.

 (5) The permissions check is being deferred to later key_permission()
     calls.

The extra values give the opportunity for LSMs to audit these situations.

[Note: This really needs overhauling so that lookup_user_key() tells
 key_task_permission() and the LSM what operation is being done and leaves
 it to those functions to decide how to map that onto the available
 permits.  However, I don't really want to make these change in the middle
 of the notifications patchset.]

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
cc: Paul Moore <paul@paul-moore.com>
cc: Stephen Smalley <stephen.smalley.work@gmail.com>
cc: Casey Schaufler <casey@schaufler-ca.com>
cc: keyrings@vger.kernel.org
cc: selinux@vger.kernel.org
2020-05-19 15:42:22 +01:00
David Howells
f7e47677e3 watch_queue: Add a key/keyring notification facility
Add a key/keyring change notification facility whereby notifications about
changes in key and keyring content and attributes can be received.

Firstly, an event queue needs to be created:

	pipe2(fds, O_NOTIFICATION_PIPE);
	ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, 256);

then a notification can be set up to report notifications via that queue:

	struct watch_notification_filter filter = {
		.nr_filters = 1,
		.filters = {
			[0] = {
				.type = WATCH_TYPE_KEY_NOTIFY,
				.subtype_filter[0] = UINT_MAX,
			},
		},
	};
	ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter);
	keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01);

After that, records will be placed into the queue when events occur in
which keys are changed in some way.  Records are of the following format:

	struct key_notification {
		struct watch_notification watch;
		__u32	key_id;
		__u32	aux;
	} *n;

Where:

	n->watch.type will be WATCH_TYPE_KEY_NOTIFY.

	n->watch.subtype will indicate the type of event, such as
	NOTIFY_KEY_REVOKED.

	n->watch.info & WATCH_INFO_LENGTH will indicate the length of the
	record.

	n->watch.info & WATCH_INFO_ID will be the second argument to
	keyctl_watch_key(), shifted.

	n->key will be the ID of the affected key.

	n->aux will hold subtype-dependent information, such as the key
	being linked into the keyring specified by n->key in the case of
	NOTIFY_KEY_LINKED.

Note that it is permissible for event records to be of variable length -
or, at least, the length may be dependent on the subtype.  Note also that
the queue can be shared between multiple notifications of various types.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
2020-05-19 15:19:06 +01:00
David Howells
998f50407f security: Add hooks to rule on setting a watch
Add security hooks that will allow an LSM to rule on whether or not a watch
may be set.  More than one hook is required as the watches watch different
types of object.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
cc: Casey Schaufler <casey@schaufler-ca.com>
cc: Stephen Smalley <sds@tycho.nsa.gov>
cc: linux-security-module@vger.kernel.org
2020-05-19 15:16:08 +01:00
David Howells
344fa64ef8 security: Add a hook for the point of notification insertion
Add a security hook that allows an LSM to rule on whether a notification
message is allowed to be inserted into a particular watch queue.

The hook is given the following information:

 (1) The credentials of the triggerer (which may be init_cred for a system
     notification, eg. a hardware error).

 (2) The credentials of the whoever set the watch.

 (3) The notification message.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
cc: Casey Schaufler <casey@schaufler-ca.com>
cc: Stephen Smalley <sds@tycho.nsa.gov>
cc: linux-security-module@vger.kernel.org
2020-05-19 15:08:23 +01:00
Alexey Gladkov
9d78edeaec proc: proc_pid_ns takes super_block as an argument
syzbot found that

  touch /proc/testfile

causes NULL pointer dereference at tomoyo_get_local_path()
because inode of the dentry is NULL.

Before c59f415a7c, Tomoyo received pid_ns from proc's s_fs_info
directly. Since proc_pid_ns() can only work with inode, using it in
the tomoyo_get_local_path() was wrong.

To avoid creating more functions for getting proc_ns, change the
argument type of the proc_pid_ns() function. Then, Tomoyo can use
the existing super_block to get pid_ns.

Link: https://lkml.kernel.org/r/0000000000002f0c7505a5b0e04c@google.com
Link: https://lkml.kernel.org/r/20200518180738.2939611-1-gladkov.alexey@gmail.com
Reported-by: syzbot+c1af344512918c61362c@syzkaller.appspotmail.com
Fixes: c59f415a7c ("Use proc_pid_ns() to get pid_namespace from the proc superblock")
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-05-19 07:07:50 -05:00
Linus Torvalds
642b151f45 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity fixes from Mimi Zohar:
 "A couple of miscellaneous bug fixes for the integrity subsystem:

  IMA:

   - Properly modify the open flags in order to calculate the file hash.

   - On systems requiring the IMA policy to be signed, the policy is
     loaded differently. Don't differentiate between "enforce" and
     either "log" or "fix" modes how the policy is loaded.

  EVM:

   - Two patches to fix an EVM race condition, normally the result of
     attempting to load an unsupported hash algorithm.

   - Use the lockless RCU version for walking an append only list"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  evm: Fix a small race in init_desc()
  evm: Fix RCU list related warnings
  ima: Fix return value of ima_write_policy()
  evm: Check also if *tfm is an error pointer in init_desc()
  ima: Set file->f_mode instead of file->f_flags in ima_calc_file_hash()
2020-05-18 11:29:21 -07:00
Zou Wei
e37986097b apparmor: Use true and false for bool variable
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>
2020-05-15 14:26:33 -07:00
Mateusz Nosek
c84b80cd41 security/apparmor/label.c: Clean code by removing redundant instructions
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>
2020-05-15 14:22:40 -07:00
Gustavo A. R. Silva
fe9fd23e3b apparmor: Replace zero-length array with flexible-array
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>
2020-05-15 13:04:55 -07:00
Alexei Starovoitov
a17b53c4a4 bpf, capability: Introduce CAP_BPF
Split BPF operations that are allowed under CAP_SYS_ADMIN into
combination of CAP_BPF, CAP_PERFMON, CAP_NET_ADMIN.
For backward compatibility include them in CAP_SYS_ADMIN as well.

The end result provides simple safety model for applications that use BPF:
- to load tracing program types
  BPF_PROG_TYPE_{KPROBE, TRACEPOINT, PERF_EVENT, RAW_TRACEPOINT, etc}
  use CAP_BPF and CAP_PERFMON
- to load networking program types
  BPF_PROG_TYPE_{SCHED_CLS, XDP, SK_SKB, etc}
  use CAP_BPF and CAP_NET_ADMIN

There are few exceptions from this rule:
- bpf_trace_printk() is allowed in networking programs, but it's using
  tracing mechanism, hence this helper needs additional CAP_PERFMON
  if networking program is using this helper.
- BPF_F_ZERO_SEED flag for hash/lru map is allowed under CAP_SYS_ADMIN only
  to discourage production use.
- BPF HW offload is allowed under CAP_SYS_ADMIN.
- bpf_probe_write_user() is allowed under CAP_SYS_ADMIN only.

CAPs are not checked at attach/detach time with two exceptions:
- loading BPF_PROG_TYPE_CGROUP_SKB is allowed for unprivileged users,
  hence CAP_NET_ADMIN is required at attach time.
- flow_dissector detach doesn't check prog FD at detach,
  hence CAP_NET_ADMIN is required at detach time.

CAP_SYS_ADMIN is required to iterate BPF objects (progs, maps, links) via get_next_id
command and convert them to file descriptor via GET_FD_BY_ID command.
This restriction guarantees that mutliple tasks with CAP_BPF are not able to
affect each other. That leads to clean isolation of tasks. For example:
task A with CAP_BPF and CAP_NET_ADMIN loads and attaches a firewall via bpf_link.
task B with the same capabilities cannot detach that firewall unless
task A explicitly passed link FD to task B via scm_rights or bpffs.
CAP_SYS_ADMIN can still detach/unload everything.

Two networking user apps with CAP_SYS_ADMIN and CAP_NET_ADMIN can
accidentely mess with each other programs and maps.
Two networking user apps with CAP_NET_ADMIN and CAP_BPF cannot affect each other.

CAP_NET_ADMIN + CAP_BPF allows networking programs access only packet data.
Such networking progs cannot access arbitrary kernel memory or leak pointers.

bpftool, bpftrace, bcc tools binaries should NOT be installed with
CAP_BPF and CAP_PERFMON, since unpriv users will be able to read kernel secrets.
But users with these two permissions will be able to use these tracing tools.

CAP_PERFMON is least secure, since it allows kprobes and kernel memory access.
CAP_NET_ADMIN can stop network traffic via iproute2.
CAP_BPF is the safest from security point of view and harmless on its own.

Having CAP_BPF and/or CAP_NET_ADMIN is not enough to write into arbitrary map
and if that map is used by firewall-like bpf prog.
CAP_BPF allows many bpf prog_load commands in parallel. The verifier
may consume large amount of memory and significantly slow down the system.

Existing unprivileged BPF operations are not affected.
In particular unprivileged users are allowed to load socket_filter and cg_skb
program types and to create array, hash, prog_array, map-in-map map types.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200513230355.7858-2-alexei.starovoitov@gmail.com
2020-05-15 17:29:41 +02:00
David S. Miller
d00f26b623 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-05-14

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Merged tag 'perf-for-bpf-2020-05-06' from tip tree that includes CAP_PERFMON.

2) support for narrow loads in bpf_sock_addr progs and additional
   helpers in cg-skb progs, from Andrey.

3) bpf benchmark runner, from Andrii.

4) arm and riscv JIT optimizations, from Luke.

5) bpf iterator infrastructure, from Yonghong.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-14 20:31:21 -07:00
Dan Carpenter
8433856947 evm: Fix a small race in init_desc()
The IS_ERR_OR_NULL() function has two conditions and if we got really
unlucky we could hit a race where "ptr" started as an error pointer and
then was set to NULL.  Both conditions would be false even though the
pointer at the end was NULL.

This patch fixes the problem by ensuring that "*tfm" can only be NULL
or valid.  I have introduced a "tmp_tfm" variable to make that work.  I
also reversed a condition and pulled the code in one tab.

Reported-by: Roberto Sassu <roberto.sassu@huawei.com>
Fixes: 53de3b080d ("evm: Check also if *tfm is an error pointer in init_desc()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Roberto Sassu <roberto.sassu@huawei.com>
Acked-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-14 19:55:54 -04:00
Jeremy Cline
60cf7c5ed5 lockdown: Allow unprivileged users to see lockdown status
A number of userspace tools, such as systemtap, need a way to see the
current lockdown state so they can gracefully deal with the kernel being
locked down. The state is already exposed in
/sys/kernel/security/lockdown, but is only readable by root. Adjust the
permissions so unprivileged users can read the state.

Fixes: 000d388ed3 ("security: Add a static lockdown policy LSM")
Cc: Frank Ch. Eigler <fche@redhat.com>
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2020-05-14 10:23:05 -07:00
YueHaibing
fe5a90b8c1 selinux: netlabel: Remove unused inline function
There's no callers in-tree.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-05-12 20:16:33 -04:00
Zou Wei
27acbf41be tomoyo: use true for bool variable
Fixes coccicheck warning:

security/tomoyo/common.c:1028:2-13: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2020-05-12 08:39:53 +09:00
YueHaibing
ef26650a20 Smack: Remove unused inline function smk_ad_setfield_u_fs_path_mnt
commit a269434d2f ("LSM: separate LSM_AUDIT_DATA_DENTRY from LSM_AUDIT_DATA_PATH")
left behind this, remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2020-05-11 10:25:37 -07:00
Eric Biggers
bce395eea0 KEYS: encrypted: use crypto_shash_tfm_digest()
Instead of manually allocating a 'struct shash_desc' on the stack and
calling crypto_shash_digest(), switch to using the new helper function
crypto_shash_tfm_digest() which does this for us.

Cc: keyrings@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-05-08 15:32:15 +10:00
Roberto Sassu
0c4395fb2a evm: Fix possible memory leak in evm_calc_hmac_or_hash()
Don't immediately return if the signature is portable and security.ima is
not present. Just set error so that memory allocated is freed before
returning from evm_calc_hmac_or_hash().

Fixes: 50b977481f ("EVM: Add support for portable signature format")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 23:36:25 -04:00
Krzysztof Struczynski
b59fda449c ima: Set again build_ima_appraise variable
After adding the new add_rule() function in commit c52657d93b
("ima: refactor ima_init_policy()"), all appraisal flags are added to the
temp_ima_appraise variable. Revert to the previous behavior instead of
removing build_ima_appraise, to benefit from the protection offered by
__ro_after_init.

The mentioned commit introduced a bug, as it makes all the flags
modifiable, while build_ima_appraise flags can be protected with
__ro_after_init.

Cc: stable@vger.kernel.org # 5.0.x
Fixes: c52657d93b ("ima: refactor ima_init_policy()")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:09 -04:00
Krzysztof Struczynski
6ee28442a4 ima: Remove redundant policy rule set in add_rules()
Function ima_appraise_flag() returns the flag to be set in
temp_ima_appraise depending on the hook identifier passed as an argument.
It is not necessary to set the flag again for the POLICY_CHECK hook.

Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:08 -04:00
Krzysztof Struczynski
1129d31b55 ima: Fix ima digest hash table key calculation
Function hash_long() accepts unsigned long, while currently only one byte
is passed from ima_hash_key(), which calculates a key for ima_htable.

Given that hashing the digest does not give clear benefits compared to
using the digest itself, remove hash_long() and return the modulus
calculated on the first two bytes of the digest with the number of slots.
Also reduce the depth of the hash table by doubling the number of slots.

Cc: stable@vger.kernel.org
Fixes: 3323eec921 ("integrity: IMA as an integrity service provider")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Acked-by: David.Laight@aculab.com (big endian system concerns)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 22:54:07 -04:00
Madhuparna Bhowmik
770f60586d evm: Fix RCU list related warnings
This patch fixes the following warning and few other instances of
traversal of evm_config_xattrnames list:

[   32.848432] =============================
[   32.848707] WARNING: suspicious RCU usage
[   32.848966] 5.7.0-rc1-00006-ga8d5875ce5f0b #1 Not tainted
[   32.849308] -----------------------------
[   32.849567] security/integrity/evm/evm_main.c:231 RCU-list traversed in non-reader section!!

Since entries are only added to the list and never deleted, use
list_for_each_entry_lockless() instead of list_for_each_entry_rcu for
traversing the list.  Also, add a relevant comment in evm_secfs.c to
indicate this fact.

Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org> (RCU viewpoint)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 21:36:32 -04:00
Roberto Sassu
2e3a34e9f4 ima: Fix return value of ima_write_policy()
This patch fixes the return value of ima_write_policy() when a new policy
is directly passed to IMA and the current policy requires appraisal of the
file containing the policy. Currently, if appraisal is not in ENFORCE mode,
ima_write_policy() returns 0 and leads user space applications to an
endless loop. Fix this issue by denying the operation regardless of the
appraisal mode.

Cc: stable@vger.kernel.org # 4.10.x
Fixes: 19f8a84713 ("ima: measure and appraise the IMA policy itself")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 21:36:31 -04:00
Roberto Sassu
53de3b080d evm: Check also if *tfm is an error pointer in init_desc()
This patch avoids a kernel panic due to accessing an error pointer set by
crypto_alloc_shash(). It occurs especially when there are many files that
require an unsupported algorithm, as it would increase the likelihood of
the following race condition:

Task A: *tfm = crypto_alloc_shash() <= error pointer
Task B: if (*tfm == NULL) <= *tfm is not NULL, use it
Task B: rc = crypto_shash_init(desc) <= panic
Task A: *tfm = NULL

This patch uses the IS_ERR_OR_NULL macro to determine whether or not a new
crypto context must be created.

Cc: stable@vger.kernel.org
Fixes: d46eb36995 ("evm: crypto hash replaced by shash")
Co-developed-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 21:30:58 -04:00
Roberto Sassu
0014cc04e8 ima: Set file->f_mode instead of file->f_flags in ima_calc_file_hash()
Commit a408e4a86b ("ima: open a new file instance if no read
permissions") tries to create a new file descriptor to calculate a file
digest if the file has not been opened with O_RDONLY flag. However, if a
new file descriptor cannot be obtained, it sets the FMODE_READ flag to
file->f_flags instead of file->f_mode.

This patch fixes this issue by replacing f_flags with f_mode as it was
before that commit.

Cc: stable@vger.kernel.org # 4.20.x
Fixes: a408e4a86b ("ima: open a new file instance if no read permissions")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-07 21:30:58 -04:00
David S. Miller
3793faad7b Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts were all overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06 22:10:13 -07:00
Alexei Starovoitov
f87b87a1c9 CAP_PERFMON for BPF
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Merge tag 'perf-for-bpf-2020-05-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into bpf-next

CAP_PERFMON for BPF
2020-05-06 17:12:44 -07:00
Casey Schaufler
4ca7528706 Smack:- Remove redundant inode_smack cache
The inode_smack cache is no longer used.
Remove it.

Signed-off-by: Vishal Goel <vishal.goel@samsung.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2020-05-06 14:46:26 -07:00
Casey Schaufler
921bb1cbb3 Smack:- Remove mutex lock "smk_lock" from inode_smack
"smk_lock" mutex is used during inode instantiation in
smack_d_instantiate()function. It has been used to avoid
simultaneous access on same inode security structure.
Since smack related initialization is done only once i.e during
inode creation. If the inode has already been instantiated then
smack_d_instantiate() function just returns without doing
anything.

So it means mutex lock is required only during inode creation.
But since 2 processes can't create same inodes or files
simultaneously. Also linking or some other file operation can't
be done simultaneously when the file is getting created since
file lookup will fail before dentry inode linkup which is done
after smack initialization.
So no mutex lock is required in inode_smack structure.

It will save memory as well as improve some performance.
If 40000 inodes are created in system, it will save 1.5 MB on
32-bit systems & 2.8 MB on 64-bit systems.

Signed-off-by: Vishal Goel <vishal.goel@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2020-05-06 14:46:26 -07:00
Casey Schaufler
84e99e58e8 Smack: slab-out-of-bounds in vsscanf
Add barrier to soob. Return -EOVERFLOW if the buffer
is exceeded.

Suggested-by: Hillf Danton <hdanton@sina.com>
Reported-by: syzbot+bfdd4a2f07be52351350@syzkaller.appspotmail.com
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2020-05-06 14:46:26 -07:00
Maninder Singh
092c94aed3 smack: remove redundant structure variable from header.
commit afb1cbe374 ("LSM: Infrastructure management
of the inode security") removed usage of smk_rcu,
thus removing it from structure.

Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2020-05-06 14:46:26 -07:00
Arnd Bergmann
00720f0e7f smack: avoid unused 'sip' variable warning
The mix of IS_ENABLED() and #ifdef checks has left a combination
that causes a warning about an unused variable:

security/smack/smack_lsm.c: In function 'smack_socket_connect':
security/smack/smack_lsm.c:2838:24: error: unused variable 'sip' [-Werror=unused-variable]
 2838 |   struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;

Change the code to use C-style checks consistently so the compiler
can handle it correctly.

Fixes: 87fbfffcc8 ("broken ping to ipv6 linklocal addresses on debian buster")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2020-05-06 14:46:26 -07:00
Ondrej Mosnacek
03414a49ad selinux: do not allocate hashtabs dynamically
It is simpler to allocate them statically in the corresponding
structure, avoiding unnecessary kmalloc() calls and pointer
dereferencing.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: manual merging required in policydb.c]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-05-01 16:34:57 -04:00
Ondrej Mosnacek
46619b44e4 selinux: fix return value on error in policydb_read()
The value of rc is still zero from the last assignment when the error
path is taken. Fix it by setting it to -ENOMEM before the
hashtab_create() call.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: e67b2ec9f6 ("selinux: store role transitions in a hash table")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-05-01 16:08:46 -04:00
Ondrej Mosnacek
3348bd33e8 selinux: simplify range_write()
No need to traverse the hashtab to count its elements, hashtab already
tracks it for us.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-05-01 16:08:04 -04:00
Wei Yongjun
4c09f8b691 selinux: fix error return code in policydb_read()
Fix to return negative error code -ENOMEM from the kvcalloc() error
handling case instead of 0, as done elsewhere in this function.

Fixes: acdf52d97f ("selinux: convert to kvmalloc")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-05-01 15:02:14 -04:00
Linus Torvalds
39e16d9342 selinux/stable-5.7 PR 20200430
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Merge tag 'selinux-pr-20200430' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux fixes from Paul Moore:
 "Two more SELinux patches to fix problems in the v5.7-rcX releases.

  Wei Yongjun's patch fixes a return code in an error path, and my patch
  fixes a problem where we were not correctly applying access controls
  to all of the netlink messages in the netlink_send LSM hook"

* tag 'selinux-pr-20200430' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: properly handle multiple messages in selinux_netlink_send()
  selinux: fix error return code in cond_read_list()
2020-04-30 16:35:45 -07:00
Paul Moore
fb73974172 selinux: properly handle multiple messages in selinux_netlink_send()
Fix the SELinux netlink_send hook to properly handle multiple netlink
messages in a single sk_buff; each message is parsed and subject to
SELinux access control.  Prior to this patch, SELinux only inspected
the first message in the sk_buff.

Cc: stable@vger.kernel.org
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-30 16:18:37 -04:00
Daniel Borkmann
0b54142e4b Merge branch 'work.sysctl' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull in Christoph Hellwig's series that changes the sysctl's ->proc_handler
methods to take kernel pointers instead. It gets rid of the set_fs address
space overrides used by BPF. As per discussion, pull in the feature branch
into bpf-next as it relates to BPF sysctl progs.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200427071508.GV23230@ZenIV.linux.org.uk/T/
2020-04-28 21:23:38 +02:00
Wei Yongjun
292fed1fc8 selinux: fix error return code in cond_read_list()
Fix to return negative error code -ENOMEM from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: 60abd3181d ("selinux: convert cond_list to array")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-27 17:44:39 -04:00
Christoph Hellwig
32927393dc sysctl: pass kernel pointers to ->proc_handler
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>
2020-04-27 02:07:40 -04:00
Alexey Gladkov
c59f415a7c Use proc_pid_ns() to get pid_namespace from the proc superblock
To get pid_namespace from the procfs superblock should be used a special
helper. This will avoid errors when s_fs_info will change the type.

Link: https://lore.kernel.org/lkml/20200423200316.164518-3-gladkov.alexey@gmail.com/
Link: https://lore.kernel.org/lkml/20200423112858.95820-1-gladkov.alexey@gmail.com/
Link: https://lore.kernel.org/lkml/06B50A1C-406F-4057-BFA8-3A7729EA7469@lca.pw/
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-04-24 16:38:30 -05:00
Ondrej Mosnacek
9521eb3ea1 selinux: don't produce incorrect filename_trans_count
I thought I fixed the counting in filename_trans_read_helper() to count
the compat rule count correctly in the final version, but it's still
wrong. To really count the same thing as in the compat path, we'd need
to add up the cardinalities of stype bitmaps of all datums.

Since the kernel currently doesn't implement an ebitmap_cardinality()
function (and computing the proper count would just waste CPU cycles
anyway), just document that we use the field only in case of the old
format and stop updating it in filename_trans_read_helper().

Fixes: 4300590243 ("selinux: implement new format of filename transitions")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-22 15:38:10 -04:00
Ingo Molnar
87cfeb1920 perf/core fixes and improvements:
kernel + tools/perf:
 
   Alexey Budankov:
 
   - Introduce CAP_PERFMON to kernel and user space.
 
 callchains:
 
   Adrian Hunter:
 
   - Allow using Intel PT to synthesize callchains for regular events.
 
   Kan Liang:
 
   - Stitch LBR records from multiple samples to get deeper backtraces,
     there are caveats, see the csets for details.
 
 perf script:
 
   Andreas Gerstmayr:
 
   - Add flamegraph.py script
 
 BPF:
 
   Jiri Olsa:
 
   - Synthesize bpf_trampoline/dispatcher ksymbol events.
 
 perf stat:
 
   Arnaldo Carvalho de Melo:
 
   - Honour --timeout for forked workloads.
 
   Stephane Eranian:
 
   - Force error in fallback on :k events, to avoid counting nothing when
     the user asks for kernel events but is not allowed to.
 
 perf bench:
 
   Ian Rogers:
 
   - Add event synthesis benchmark.
 
 tools api fs:
 
   Stephane Eranian:
 
  - Make xxx__mountpoint() more scalable
 
 libtraceevent:
 
   He Zhe:
 
   - Handle return value of asprintf.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-5.8-20200420' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core fixes and improvements from Arnaldo Carvalho de Melo:

kernel + tools/perf:

  Alexey Budankov:

  - Introduce CAP_PERFMON to kernel and user space.

callchains:

  Adrian Hunter:

  - Allow using Intel PT to synthesize callchains for regular events.

  Kan Liang:

  - Stitch LBR records from multiple samples to get deeper backtraces,
    there are caveats, see the csets for details.

perf script:

  Andreas Gerstmayr:

  - Add flamegraph.py script

BPF:

  Jiri Olsa:

  - Synthesize bpf_trampoline/dispatcher ksymbol events.

perf stat:

  Arnaldo Carvalho de Melo:

  - Honour --timeout for forked workloads.

  Stephane Eranian:

  - Force error in fallback on :k events, to avoid counting nothing when
    the user asks for kernel events but is not allowed to.

perf bench:

  Ian Rogers:

  - Add event synthesis benchmark.

tools api fs:

  Stephane Eranian:

 - Make xxx__mountpoint() more scalable

libtraceevent:

  He Zhe:

  - Handle return value of asprintf.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-22 14:08:28 +02:00
Roberto Sassu
2592677c04 ima: Use ima_hash_algo for collision detection in the measurement list
Before calculating a digest for each PCR bank, collisions were detected
with a SHA1 digest. This patch includes ima_hash_algo among the algorithms
used to calculate the template digest and checks collisions on that digest.

The position in the measurement entry array of the template digest
calculated with the IMA default hash algorithm is stored in the
ima_hash_algo_idx global variable and is determined at IMA initialization
time.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu
1ea973df6e ima: Calculate and extend PCR with digests in ima_template_entry
This patch modifies ima_calc_field_array_hash() to calculate a template
digest for each allocated PCR bank and SHA1. It also passes the tpm_digest
array of the template entry to ima_pcr_extend() or in case of a violation,
the pre-initialized digests array filled with 0xff.

Padding with zeros is still done if the mapping between TPM algorithm ID
and crypto ID is unknown.

This patch calculates again the template digest when a measurement list is
restored. Copying only the SHA1 digest (due to the limitation of the
current measurement list format) is not sufficient, as hash collision
detection will be done on the digest calculated with the IMA default hash
algorithm.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu
6d94809af6 ima: Allocate and initialize tfm for each PCR bank
This patch creates a crypto_shash structure for each allocated PCR bank and
for SHA1 if a bank with that algorithm is not currently allocated.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu
aa724fe18a ima: Switch to dynamically allocated buffer for template digests
This patch dynamically allocates the array of tpm_digest structures in
ima_alloc_init_template() and ima_restore_template_data(). The size of the
array is equal to the number of PCR banks plus ima_extra_slots, to make
room for SHA1 and the IMA default hash algorithm, when PCR banks with those
algorithms are not allocated.

Calculating the SHA1 digest is mandatory, as SHA1 still remains the default
hash algorithm for the measurement list. When IMA will support the Crypto
Agile format, remaining digests will be also provided.

The position in the measurement entry array of the SHA1 digest is stored in
the ima_sha1_idx global variable and is determined at IMA initialization
time.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu
7ca79645a1 ima: Store template digest directly in ima_template_entry
In preparation for the patch that calculates a digest for each allocated
PCR bank, this patch passes to ima_calc_field_array_hash() the
ima_template_entry structure, so that digests can be directly stored in
that structure instead of ima_digest_data.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu
e144d6b265 ima: Evaluate error in init_ima()
Evaluate error in init_ima() before register_blocking_lsm_notifier() and
return if not zero.

Cc: stable@vger.kernel.org # 5.3.x
Fixes: b169424551 ("ima: use the lsm policy update notifier")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Roberto Sassu
6f1a1d103b ima: Switch to ima_hash_algo for boot aggregate
boot_aggregate is the first entry of IMA measurement list. Its purpose is
to link pre-boot measurements to IMA measurements. As IMA was designed to
work with a TPM 1.2, the SHA1 PCR bank was always selected even if a
TPM 2.0 with support for stronger hash algorithms is available.

This patch first tries to find a PCR bank with the IMA default hash
algorithm. If it does not find it, it selects the SHA256 PCR bank for
TPM 2.0 and SHA1 for TPM 1.2. Ultimately, it selects SHA1 also for TPM 2.0
if the SHA256 PCR bank is not found.

If none of the PCR banks above can be found, boot_aggregate file digest is
filled with zeros, as for TPM bypass, making it impossible to perform a
remote attestation of the system.

Cc: stable@vger.kernel.org # 5.1.x
Fixes: 879b589210 ("tpm: retrieve digest size of unknown algorithms with PCR read")
Reported-by: Jerry Snitselaar <jsnitsel@redhat.com>
Suggested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-04-19 22:03:39 -04:00
Ondrej Mosnacek
4300590243 selinux: implement new format of filename transitions
Implement a new, more space-efficient way of storing filename
transitions in the binary policy. The internal structures have already
been converted to this new representation; this patch just implements
reading/writing an equivalent represntation from/to the binary policy.

This new format reduces the size of Fedora policy from 7.6 MB to only
3.3 MB (with policy optimization enabled in both cases). With the
unconfined module disabled, the size is reduced from 3.3 MB to 2.4 MB.

The time to load policy into kernel is also shorter with the new format.
On Fedora Rawhide x86_64 it dropped from 157 ms to 106 ms; without the
unconfined module from 115 ms to 105 ms.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-17 16:42:01 -04:00
Ondrej Mosnacek
225621c934 selinux: move context hashing under sidtab
Now that context hash computation no longer depends on policydb, we can
simplify things by moving the context hashing completely under sidtab.
The hash is still cached in sidtab entries, but not for the in-flight
context structures.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-17 16:04:38 -04:00
Ondrej Mosnacek
5007728980 selinux: hash context structure directly
Always hashing the string representation is inefficient. Just hash the
contents of the structure directly (using jhash). If the context is
invalid (str & len are set), then hash the string as before, otherwise
hash the structured data.

Since the context hashing function is now faster (about 10 times), this
patch decreases the overhead of security_transition_sid(), which is
called from many hooks.

The jhash function seemed as a good choice, since it is used as the
default hashing algorithm in rhashtable.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Jeff Vander Stoep <jeffv@google.com>
Tested-by: Jeff Vander Stoep <jeffv@google.com>
[PM: fixed some spelling errors in the comments pointed out by JVS]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-17 16:04:34 -04:00
Ondrej Mosnacek
e67b2ec9f6 selinux: store role transitions in a hash table
Currently, they are stored in a linked list, which adds significant
overhead to security_transition_sid(). On Fedora, with 428 role
transitions in policy, converting this list to a hash table cuts down
its run time by about 50%. This was measured by running 'stress-ng --msg
1 --msg-ops 100000' under perf with and without this patch.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-17 15:20:22 -04:00
Linus Torvalds
9786cab674 selinux/stable-5.7 PR 20200416
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Merge tag 'selinux-pr-20200416' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux fix from Paul Moore:
 "One small SELinux fix to ensure we cleanup properly on an error
  condition"

* tag 'selinux-pr-20200416' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: free str on error in str_read()
2020-04-16 10:45:47 -07:00
Vasily Averin
86d32f9a7c keys: Fix proc_keys_next to increase position index
If seq_file .next function does not change position index,
read after some lseek can generate unexpected output:

    $ dd if=/proc/keys bs=1  # full usual output
    0f6bfdf5 I--Q---     2 perm 3f010000  1000  1000 user      4af2f79ab8848d0a: 740
    1fb91b32 I--Q---     3 perm 1f3f0000  1000 65534 keyring   _uid.1000: 2
    27589480 I--Q---     1 perm 0b0b0000     0     0 user      invocation_id: 16
    2f33ab67 I--Q---   152 perm 3f030000     0     0 keyring   _ses: 2
    33f1d8fa I--Q---     4 perm 3f030000  1000  1000 keyring   _ses: 1
    3d427fda I--Q---     2 perm 3f010000  1000  1000 user      69ec44aec7678e5a: 740
    3ead4096 I--Q---     1 perm 1f3f0000  1000 65534 keyring   _uid_ses.1000: 1
    521+0 records in
    521+0 records out
    521 bytes copied, 0,00123769 s, 421 kB/s

But a read after lseek in middle of last line results in the partial
last line and then a repeat of the final line:

    $ dd if=/proc/keys bs=500 skip=1
    dd: /proc/keys: cannot skip to specified offset
    g   _uid_ses.1000: 1
    3ead4096 I--Q---     1 perm 1f3f0000  1000 65534 keyring   _uid_ses.1000: 1
    0+1 records in
    0+1 records out
    97 bytes copied, 0,000135035 s, 718 kB/s

and a read after lseek beyond end of file results in the last line being
shown:

    $ dd if=/proc/keys bs=1000 skip=1   # read after lseek beyond end of file
    dd: /proc/keys: cannot skip to specified offset
    3ead4096 I--Q---     1 perm 1f3f0000  1000 65534 keyring   _uid_ses.1000: 1
    0+1 records in
    0+1 records out
    76 bytes copied, 0,000119981 s, 633 kB/s

See https://bugzilla.kernel.org/show_bug.cgi?id=206283

Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code ...")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-16 10:10:50 -07:00
Alexey Budankov
9807372822 capabilities: Introduce CAP_PERFMON to kernel and user space
Introduce the CAP_PERFMON capability designed to secure system
performance monitoring and observability operations so that CAP_PERFMON
can assist CAP_SYS_ADMIN capability in its governing role for
performance monitoring and observability subsystems.

CAP_PERFMON hardens system security and integrity during performance
monitoring and observability operations by decreasing attack surface that
is available to a CAP_SYS_ADMIN privileged process [2]. Providing the access
to system performance monitoring and observability operations under CAP_PERFMON
capability singly, without the rest of CAP_SYS_ADMIN credentials, excludes
chances to misuse the credentials and makes the operation more secure.

Thus, CAP_PERFMON implements the principle of least privilege for
performance monitoring and observability operations (POSIX IEEE 1003.1e:
2.2.2.39 principle of least privilege: A security design principle that
  states that a process or program be granted only those privileges
(e.g., capabilities) necessary to accomplish its legitimate function,
and only for the time that such privileges are actually required)

CAP_PERFMON meets the demand to secure system performance monitoring and
observability operations for adoption in security sensitive, restricted,
multiuser production environments (e.g. HPC clusters, cloud and virtual compute
environments), where root or CAP_SYS_ADMIN credentials are not available to
mass users of a system, and securely unblocks applicability and scalability
of system performance monitoring and observability operations beyond root
and CAP_SYS_ADMIN use cases.

CAP_PERFMON takes over CAP_SYS_ADMIN credentials related to system performance
monitoring and observability operations and balances amount of CAP_SYS_ADMIN
credentials following the recommendations in the capabilities man page [1]
for CAP_SYS_ADMIN: "Note: this capability is overloaded; see Notes to kernel
developers, below." For backward compatibility reasons access to system
performance monitoring and observability subsystems of the kernel remains
open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN capability
usage for secure system performance monitoring and observability operations
is discouraged with respect to the designed CAP_PERFMON capability.

Although the software running under CAP_PERFMON can not ensure avoidance
of related hardware issues, the software can still mitigate these issues
following the official hardware issues mitigation procedure [2]. The bugs
in the software itself can be fixed following the standard kernel development
process [3] to maintain and harden security of system performance monitoring
and observability operations.

[1] http://man7.org/linux/man-pages/man7/capabilities.7.html
[2] https://www.kernel.org/doc/html/latest/process/embargoed-hardware-issues.html
[3] https://www.kernel.org/doc/html/latest/admin-guide/security-bugs.html

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/5590d543-82c6-490a-6544-08e6a5517db0@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:06 -03:00
Ondrej Mosnacek
433e3aa377 selinux: drop unnecessary smp_load_acquire() call
In commit 66f8e2f03c ("selinux: sidtab reverse lookup hash table") the
corresponding load is moved under the spin lock, so there is no race
possible and we can read the count directly. The smp_store_release() is
still needed to avoid racing with the lock-free readers.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-15 18:27:35 -04:00
Ondrej Mosnacek
af15f14c8c selinux: free str on error in str_read()
In [see "Fixes:"] I missed the fact that str_read() may give back an
allocated pointer even if it returns an error, causing a potential
memory leak in filename_trans_read_one(). Fix this by making the
function free the allocated string whenever it returns a non-zero value,
which also makes its behavior more obvious and prevents repeating the
same mistake in the future.

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1461665 ("Resource leaks")
Fixes: c3a276111e ("selinux: optimize storage of filename transitions")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-15 17:23:16 -04:00
Zou Wei
4b8503967e selinux: fix warning Comparison to bool
fix below warnings reported by coccicheck

security/selinux/ss/mls.c:539:39-43: WARNING: Comparison to bool
security/selinux/ss/services.c:1815:46-50: WARNING: Comparison to bool
security/selinux/ss/services.c:1827:46-50: WARNING: Comparison to bool

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-14 18:01:18 -04:00
Odin Ugedal
eec8fd0277 device_cgroup: Cleanup cgroup eBPF device filter code
Original cgroup v2 eBPF code for filtering device access made it
possible to compile with CONFIG_CGROUP_DEVICE=n and still use the eBPF
filtering. Change
commit 4b7d4d453f ("device_cgroup: Export devcgroup_check_permission")
reverted this, making it required to set it to y.

Since the device filtering (and all the docs) for cgroup v2 is no longer
a "device controller" like it was in v1, someone might compile their
kernel with CONFIG_CGROUP_DEVICE=n. Then (for linux 5.5+) the eBPF
filter will not be invoked, and all processes will be allowed access
to all devices, no matter what the eBPF filter says.

Signed-off-by: Odin Ugedal <odin@ugedal.com>
Acked-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2020-04-13 14:41:54 -04:00
John Johansen
c27c6bd2c4 apparmor: ensure that dfa state tables have entries
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>
2020-04-08 04:42:48 -07:00
Linus Torvalds
4c205c84e2 Keyrings fixes
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Merge tag 'keys-fixes-20200329' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull keyrings fixes from David Howells:
 "Here's a couple of patches that fix a circular dependency between
  holding key->sem and mm->mmap_sem when reading data from a key.

  One potential issue is that a filesystem looking to use a key inside,
  say, ->readpages() could deadlock if the key being read is the key
  that's required and the buffer the key is being read into is on a page
  that needs to be fetched.

  The case actually detected is a bit more involved - with a filesystem
  calling request_key() and locking the target keyring for write - which
  could be being read"

* tag 'keys-fixes-20200329' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  KEYS: Avoid false positive ENOMEM error on key read
  KEYS: Don't write out to userspace while holding key semaphore
2020-04-04 12:24:47 -07:00
Linus Torvalds
ff2ae607c6 SPDX patches for 5.7-rc1.
Here are 3 SPDX patches for 5.7-rc1.
 
 One fixes up the SPDX tag for a single driver, while the other two go
 through the tree and add SPDX tags for all of the .gitignore files as
 needed.
 
 Nothing too complex, but you will get a merge conflict with your current
 tree, that should be trivial to handle (one file modified by two things,
 one file deleted.)
 
 All 3 of these have been in linux-next for a while, with no reported
 issues other than the merge conflict.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments
2020-04-03 13:12:26 -07:00
Linus Torvalds
7f218319ca Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
 "Just a couple of updates for linux-5.7:

   - A new Kconfig option to enable IMA architecture specific runtime
     policy rules needed for secure and/or trusted boot, as requested.

   - Some message cleanup (eg. pr_fmt, additional error messages)"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  ima: add a new CONFIG for loading arch-specific policies
  integrity: Remove duplicate pr_fmt definitions
  IMA: Add log statements for failure conditions
  IMA: Update KBUILD_MODNAME for IMA files to ima
2020-04-02 14:49:46 -07:00
Linus Torvalds
29d9f30d4c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Fix the iwlwifi regression, from Johannes Berg.

   2) Support BSS coloring and 802.11 encapsulation offloading in
      hardware, from John Crispin.

   3) Fix some potential Spectre issues in qtnfmac, from Sergey
      Matyukevich.

   4) Add TTL decrement action to openvswitch, from Matteo Croce.

   5) Allow paralleization through flow_action setup by not taking the
      RTNL mutex, from Vlad Buslov.

   6) A lot of zero-length array to flexible-array conversions, from
      Gustavo A. R. Silva.

   7) Align XDP statistics names across several drivers for consistency,
      from Lorenzo Bianconi.

   8) Add various pieces of infrastructure for offloading conntrack, and
      make use of it in mlx5 driver, from Paul Blakey.

   9) Allow using listening sockets in BPF sockmap, from Jakub Sitnicki.

  10) Lots of parallelization improvements during configuration changes
      in mlxsw driver, from Ido Schimmel.

  11) Add support to devlink for generic packet traps, which report
      packets dropped during ACL processing. And use them in mlxsw
      driver. From Jiri Pirko.

  12) Support bcmgenet on ACPI, from Jeremy Linton.

  13) Make BPF compatible with RT, from Thomas Gleixnet, Alexei
      Starovoitov, and your's truly.

  14) Support XDP meta-data in virtio_net, from Yuya Kusakabe.

  15) Fix sysfs permissions when network devices change namespaces, from
      Christian Brauner.

  16) Add a flags element to ethtool_ops so that drivers can more simply
      indicate which coalescing parameters they actually support, and
      therefore the generic layer can validate the user's ethtool
      request. Use this in all drivers, from Jakub Kicinski.

  17) Offload FIFO qdisc in mlxsw, from Petr Machata.

  18) Support UDP sockets in sockmap, from Lorenz Bauer.

  19) Fix stretch ACK bugs in several TCP congestion control modules,
      from Pengcheng Yang.

  20) Support virtual functiosn in octeontx2 driver, from Tomasz
      Duszynski.

  21) Add region operations for devlink and use it in ice driver to dump
      NVM contents, from Jacob Keller.

  22) Add support for hw offload of MACSEC, from Antoine Tenart.

  23) Add support for BPF programs that can be attached to LSM hooks,
      from KP Singh.

  24) Support for multiple paths, path managers, and counters in MPTCP.
      From Peter Krystad, Paolo Abeni, Florian Westphal, Davide Caratti,
      and others.

  25) More progress on adding the netlink interface to ethtool, from
      Michal Kubecek"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2121 commits)
  net: ipv6: rpl_iptunnel: Fix potential memory leak in rpl_do_srh_inline
  cxgb4/chcr: nic-tls stats in ethtool
  net: dsa: fix oops while probing Marvell DSA switches
  net/bpfilter: remove superfluous testing message
  net: macb: Fix handling of fixed-link node
  net: dsa: ksz: Select KSZ protocol tag
  netdevsim: dev: Fix memory leak in nsim_dev_take_snapshot_write
  net: stmmac: add EHL 2.5Gbps PCI info and PCI ID
  net: stmmac: add EHL PSE0 & PSE1 1Gbps PCI info and PCI ID
  net: stmmac: create dwmac-intel.c to contain all Intel platform
  net: dsa: bcm_sf2: Support specifying VLAN tag egress rule
  net: dsa: bcm_sf2: Add support for matching VLAN TCI
  net: dsa: bcm_sf2: Move writing of CFP_DATA(5) into slicing functions
  net: dsa: bcm_sf2: Check earlier for FLOW_EXT and FLOW_MAC_EXT
  net: dsa: bcm_sf2: Disable learning for ASP port
  net: dsa: b53: Deny enslaving port 7 for 7278 into a bridge
  net: dsa: b53: Prevent tagged VLAN on port 7 for 7278
  net: dsa: b53: Restore VLAN entries upon (re)configuration
  net: dsa: bcm_sf2: Fix overflow checks
  hv_netvsc: Remove unnecessary round_up for recv_completion_cnt
  ...
2020-03-31 17:29:33 -07:00
Linus Torvalds
b3aa112d57 selinux/stable-5.7 PR 20200330
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Merge tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux updates from Paul Moore:
 "We've got twenty SELinux patches for the v5.7 merge window, the
  highlights are below:

   - Deprecate setting /sys/fs/selinux/checkreqprot to 1.

     This flag was originally created to deal with legacy userspace and
     the READ_IMPLIES_EXEC personality flag. We changed the default from
     1 to 0 back in Linux v4.4 and now we are taking the next step of
     deprecating it, at some point in the future we will take the final
     step of rejecting 1.

   - Allow kernfs symlinks to inherit the SELinux label of the parent
     directory. In order to preserve backwards compatibility this is
     protected by the genfs_seclabel_symlinks SELinux policy capability.

   - Optimize how we store filename transitions in the kernel, resulting
     in some significant improvements to policy load times.

   - Do a better job calculating our internal hash table sizes which
     resulted in additional policy load improvements and likely general
     SELinux performance improvements as well.

   - Remove the unused initial SIDs (labels) and improve how we handle
     initial SIDs.

   - Enable per-file labeling for the bpf filesystem.

   - Ensure that we properly label NFS v4.2 filesystems to avoid a
     temporary unlabeled condition.

   - Add some missing XFS quota command types to the SELinux quota
     access controls.

   - Fix a problem where we were not updating the seq_file position
     index correctly in selinuxfs.

   - We consolidate some duplicated code into helper functions.

   - A number of list to array conversions.

   - Update Stephen Smalley's email address in MAINTAINERS"

* tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: clean up indentation issue with assignment statement
  NFS: Ensure security label is set for root inode
  MAINTAINERS: Update my email address
  selinux: avtab_init() and cond_policydb_init() return void
  selinux: clean up error path in policydb_init()
  selinux: remove unused initial SIDs and improve handling
  selinux: reduce the use of hard-coded hash sizes
  selinux: Add xfs quota command types
  selinux: optimize storage of filename transitions
  selinux: factor out loop body from filename_trans_read()
  security: selinux: allow per-file labeling for bpffs
  selinux: generalize evaluate_cond_node()
  selinux: convert cond_expr to array
  selinux: convert cond_av_list to array
  selinux: convert cond_list to array
  selinux: sel_avc_get_stat_idx should increase position index
  selinux: allow kernfs symlinks to inherit parent directory context
  selinux: simplify evaluate_cond_node()
  Documentation,selinux: deprecate setting checkreqprot to 1
  selinux: move status variables out of selinux_ss
2020-03-31 15:07:55 -07:00
Colin Ian King
c753924b62 selinux: clean up indentation issue with assignment statement
The assignment of e->type_names is indented one level too deep,
clean this up by removing the extraneous tab.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-03-30 19:57:07 -04:00
Linus Torvalds
a776c270a0 Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The EFI changes in this cycle are much larger than usual, for two
  (positive) reasons:

   - The GRUB project is showing signs of life again, resulting in the
     introduction of the generic Linux/UEFI boot protocol, instead of
     x86 specific hacks which are increasingly difficult to maintain.
     There's hope that all future extensions will now go through that
     boot protocol.

   - Preparatory work for RISC-V EFI support.

  The main changes are:

   - Boot time GDT handling changes

   - Simplify handling of EFI properties table on arm64

   - Generic EFI stub cleanups, to improve command line handling, file
     I/O, memory allocation, etc.

   - Introduce a generic initrd loading method based on calling back
     into the firmware, instead of relying on the x86 EFI handover
     protocol or device tree.

   - Introduce a mixed mode boot method that does not rely on the x86
     EFI handover protocol either, and could potentially be adopted by
     other architectures (if another one ever surfaces where one
     execution mode is a superset of another)

   - Clean up the contents of 'struct efi', and move out everything that
     doesn't need to be stored there.

   - Incorporate support for UEFI spec v2.8A changes that permit
     firmware implementations to return EFI_UNSUPPORTED from UEFI
     runtime services at OS runtime, and expose a mask of which ones are
     supported or unsupported via a configuration table.

   - Partial fix for the lack of by-VA cache maintenance in the
     decompressor on 32-bit ARM.

   - Changes to load device firmware from EFI boot service memory
     regions

   - Various documentation updates and minor code cleanups and fixes"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (114 commits)
  efi/libstub/arm: Fix spurious message that an initrd was loaded
  efi/libstub/arm64: Avoid image_base value from efi_loaded_image
  partitions/efi: Fix partition name parsing in GUID partition entry
  efi/x86: Fix cast of image argument
  efi/libstub/x86: Use ULONG_MAX as upper bound for all allocations
  efi: Fix a mistype in comments mentioning efivar_entry_iter_begin()
  efi/libstub: Avoid linking libstub/lib-ksyms.o into vmlinux
  efi/x86: Preserve %ebx correctly in efi_set_virtual_address_map()
  efi/x86: Ignore the memory attributes table on i386
  efi/x86: Don't relocate the kernel unless necessary
  efi/x86: Remove extra headroom for setup block
  efi/x86: Add kernel preferred address to PE header
  efi/x86: Decompress at start of PE image load address
  x86/boot/compressed/32: Save the output address instead of recalculating it
  efi/libstub/x86: Deal with exit() boot service returning
  x86/boot: Use unsigned comparison for addresses
  efi/x86: Avoid using code32_start
  efi/x86: Make efi32_pe_entry() more readable
  efi/x86: Respect 32-bit ABI in efi32_pe_entry()
  efi/x86: Annotate the LOADED_IMAGE_PROTOCOL_GUID with SYM_DATA
  ...
2020-03-30 16:13:08 -07:00
KP Singh
520b7aa00d bpf: lsm: Initialize the BPF LSM hooks
* The hooks are initialized using the definitions in
  include/linux/lsm_hook_defs.h.
* The LSM can be enabled / disabled with CONFIG_BPF_LSM.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-6-kpsingh@chromium.org
2020-03-30 01:34:00 +02:00
KP Singh
98e828a065 security: Refactor declaration of LSM hooks
The information about the different types of LSM hooks is scattered
in two locations i.e. union security_list_options and
struct security_hook_heads. Rather than duplicating this information
even further for BPF_PROG_TYPE_LSM, define all the hooks with the
LSM_HOOK macro in lsm_hook_defs.h which is then used to generate all
the data structures required by the LSM framework.

The LSM hooks are defined as:

  LSM_HOOK(<return_type>, <default_value>, <hook_name>, args...)

with <default_value> acccessible in security.c as:

  LSM_RET_DEFAULT(<hook_name>)

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-3-kpsingh@chromium.org
2020-03-30 01:34:00 +02:00
Waiman Long
4f0882491a KEYS: Avoid false positive ENOMEM error on key read
By allocating a kernel buffer with a user-supplied buffer length, it
is possible that a false positive ENOMEM error may be returned because
the user-supplied length is just too large even if the system do have
enough memory to hold the actual key data.

Moreover, if the buffer length is larger than the maximum amount of
memory that can be returned by kmalloc() (2^(MAX_ORDER-1) number of
pages), a warning message will also be printed.

To reduce this possibility, we set a threshold (PAGE_SIZE) over which we
do check the actual key length first before allocating a buffer of the
right size to hold it. The threshold is arbitrary, it is just used to
trigger a buffer length check. It does not limit the actual key length
as long as there is enough memory to satisfy the memory request.

To further avoid large buffer allocation failure due to page
fragmentation, kvmalloc() is used to allocate the buffer so that vmapped
pages can be used when there is not a large enough contiguous set of
pages available for allocation.

In the extremely unlikely scenario that the key keeps on being changed
and made longer (still <= buflen) in between 2 __keyctl_read_key()
calls, the __keyctl_read_key() calling loop in keyctl_read_key() may
have to be iterated a large number of times, but definitely not infinite.

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-29 12:40:41 +01:00
Waiman Long
d3ec10aa95 KEYS: Don't write out to userspace while holding key semaphore
A lockdep circular locking dependency report was seen when running a
keyutils test:

[12537.027242] ======================================================
[12537.059309] WARNING: possible circular locking dependency detected
[12537.088148] 4.18.0-147.7.1.el8_1.x86_64+debug #1 Tainted: G OE    --------- -  -
[12537.125253] ------------------------------------------------------
[12537.153189] keyctl/25598 is trying to acquire lock:
[12537.175087] 000000007c39f96c (&mm->mmap_sem){++++}, at: __might_fault+0xc4/0x1b0
[12537.208365]
[12537.208365] but task is already holding lock:
[12537.234507] 000000003de5b58d (&type->lock_class){++++}, at: keyctl_read_key+0x15a/0x220
[12537.270476]
[12537.270476] which lock already depends on the new lock.
[12537.270476]
[12537.307209]
[12537.307209] the existing dependency chain (in reverse order) is:
[12537.340754]
[12537.340754] -> #3 (&type->lock_class){++++}:
[12537.367434]        down_write+0x4d/0x110
[12537.385202]        __key_link_begin+0x87/0x280
[12537.405232]        request_key_and_link+0x483/0xf70
[12537.427221]        request_key+0x3c/0x80
[12537.444839]        dns_query+0x1db/0x5a5 [dns_resolver]
[12537.468445]        dns_resolve_server_name_to_ip+0x1e1/0x4d0 [cifs]
[12537.496731]        cifs_reconnect+0xe04/0x2500 [cifs]
[12537.519418]        cifs_readv_from_socket+0x461/0x690 [cifs]
[12537.546263]        cifs_read_from_socket+0xa0/0xe0 [cifs]
[12537.573551]        cifs_demultiplex_thread+0x311/0x2db0 [cifs]
[12537.601045]        kthread+0x30c/0x3d0
[12537.617906]        ret_from_fork+0x3a/0x50
[12537.636225]
[12537.636225] -> #2 (root_key_user.cons_lock){+.+.}:
[12537.664525]        __mutex_lock+0x105/0x11f0
[12537.683734]        request_key_and_link+0x35a/0xf70
[12537.705640]        request_key+0x3c/0x80
[12537.723304]        dns_query+0x1db/0x5a5 [dns_resolver]
[12537.746773]        dns_resolve_server_name_to_ip+0x1e1/0x4d0 [cifs]
[12537.775607]        cifs_reconnect+0xe04/0x2500 [cifs]
[12537.798322]        cifs_readv_from_socket+0x461/0x690 [cifs]
[12537.823369]        cifs_read_from_socket+0xa0/0xe0 [cifs]
[12537.847262]        cifs_demultiplex_thread+0x311/0x2db0 [cifs]
[12537.873477]        kthread+0x30c/0x3d0
[12537.890281]        ret_from_fork+0x3a/0x50
[12537.908649]
[12537.908649] -> #1 (&tcp_ses->srv_mutex){+.+.}:
[12537.935225]        __mutex_lock+0x105/0x11f0
[12537.954450]        cifs_call_async+0x102/0x7f0 [cifs]
[12537.977250]        smb2_async_readv+0x6c3/0xc90 [cifs]
[12538.000659]        cifs_readpages+0x120a/0x1e50 [cifs]
[12538.023920]        read_pages+0xf5/0x560
[12538.041583]        __do_page_cache_readahead+0x41d/0x4b0
[12538.067047]        ondemand_readahead+0x44c/0xc10
[12538.092069]        filemap_fault+0xec1/0x1830
[12538.111637]        __do_fault+0x82/0x260
[12538.129216]        do_fault+0x419/0xfb0
[12538.146390]        __handle_mm_fault+0x862/0xdf0
[12538.167408]        handle_mm_fault+0x154/0x550
[12538.187401]        __do_page_fault+0x42f/0xa60
[12538.207395]        do_page_fault+0x38/0x5e0
[12538.225777]        page_fault+0x1e/0x30
[12538.243010]
[12538.243010] -> #0 (&mm->mmap_sem){++++}:
[12538.267875]        lock_acquire+0x14c/0x420
[12538.286848]        __might_fault+0x119/0x1b0
[12538.306006]        keyring_read_iterator+0x7e/0x170
[12538.327936]        assoc_array_subtree_iterate+0x97/0x280
[12538.352154]        keyring_read+0xe9/0x110
[12538.370558]        keyctl_read_key+0x1b9/0x220
[12538.391470]        do_syscall_64+0xa5/0x4b0
[12538.410511]        entry_SYSCALL_64_after_hwframe+0x6a/0xdf
[12538.435535]
[12538.435535] other info that might help us debug this:
[12538.435535]
[12538.472829] Chain exists of:
[12538.472829]   &mm->mmap_sem --> root_key_user.cons_lock --> &type->lock_class
[12538.472829]
[12538.524820]  Possible unsafe locking scenario:
[12538.524820]
[12538.551431]        CPU0                    CPU1
[12538.572654]        ----                    ----
[12538.595865]   lock(&type->lock_class);
[12538.613737]                                lock(root_key_user.cons_lock);
[12538.644234]                                lock(&type->lock_class);
[12538.672410]   lock(&mm->mmap_sem);
[12538.687758]
[12538.687758]  *** DEADLOCK ***
[12538.687758]
[12538.714455] 1 lock held by keyctl/25598:
[12538.732097]  #0: 000000003de5b58d (&type->lock_class){++++}, at: keyctl_read_key+0x15a/0x220
[12538.770573]
[12538.770573] stack backtrace:
[12538.790136] CPU: 2 PID: 25598 Comm: keyctl Kdump: loaded Tainted: G
[12538.844855] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 12/27/2015
[12538.881963] Call Trace:
[12538.892897]  dump_stack+0x9a/0xf0
[12538.907908]  print_circular_bug.isra.25.cold.50+0x1bc/0x279
[12538.932891]  ? save_trace+0xd6/0x250
[12538.948979]  check_prev_add.constprop.32+0xc36/0x14f0
[12538.971643]  ? keyring_compare_object+0x104/0x190
[12538.992738]  ? check_usage+0x550/0x550
[12539.009845]  ? sched_clock+0x5/0x10
[12539.025484]  ? sched_clock_cpu+0x18/0x1e0
[12539.043555]  __lock_acquire+0x1f12/0x38d0
[12539.061551]  ? trace_hardirqs_on+0x10/0x10
[12539.080554]  lock_acquire+0x14c/0x420
[12539.100330]  ? __might_fault+0xc4/0x1b0
[12539.119079]  __might_fault+0x119/0x1b0
[12539.135869]  ? __might_fault+0xc4/0x1b0
[12539.153234]  keyring_read_iterator+0x7e/0x170
[12539.172787]  ? keyring_read+0x110/0x110
[12539.190059]  assoc_array_subtree_iterate+0x97/0x280
[12539.211526]  keyring_read+0xe9/0x110
[12539.227561]  ? keyring_gc_check_iterator+0xc0/0xc0
[12539.249076]  keyctl_read_key+0x1b9/0x220
[12539.266660]  do_syscall_64+0xa5/0x4b0
[12539.283091]  entry_SYSCALL_64_after_hwframe+0x6a/0xdf

One way to prevent this deadlock scenario from happening is to not
allow writing to userspace while holding the key semaphore. Instead,
an internal buffer is allocated for getting the keys out from the
read method first before copying them out to userspace without holding
the lock.

That requires taking out the __user modifier from all the relevant
read methods as well as additional changes to not use any userspace
write helpers. That is,

  1) The put_user() call is replaced by a direct copy.
  2) The copy_to_user() call is replaced by memcpy().
  3) All the fault handling code is removed.

Compiling on a x86-64 system, the size of the rxrpc_read() function is
reduced from 3795 bytes to 2384 bytes with this patch.

Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2020-03-29 12:40:41 +01:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Masahiro Yamada
2985bed680 .gitignore: remove too obvious comments
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>
2020-03-25 11:50:28 +01:00
Yang Xu
2e356101e7 KEYS: reaching the keys quotas correctly
Currently, when we add a new user key, the calltrace as below:

add_key()
  key_create_or_update()
    key_alloc()
    __key_instantiate_and_link
      generic_key_instantiate
        key_payload_reserve
          ......

Since commit a08bf91ce2 ("KEYS: allow reaching the keys quotas exactly"),
we can reach max bytes/keys in key_alloc, but we forget to remove this
limit when we reserver space for payload in key_payload_reserve. So we
can only reach max keys but not max bytes when having delta between plen
and type->def_datalen. Remove this limit when instantiating the key, so we
can keep consistent with key_alloc.

Also, fix the similar problem in keyctl_chown_key().

Fixes: 0b77f5bfb4 ("keys: make the keyring quotas controllable through /proc/sys")
Fixes: a08bf91ce2 ("KEYS: allow reaching the keys quotas exactly")
Cc: stable@vger.kernel.org # 5.0.x
Cc: Eric Biggers <ebiggers@google.com>
Signed-off-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2020-03-15 20:59:50 +02:00
Nayna Jain
9e2b4be377 ima: add a new CONFIG for loading arch-specific policies
Every time a new architecture defines the IMA architecture specific
functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA
include file needs to be updated. To avoid this "noise", this patch
defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing
the different architectures to select it.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Philipp Rudo <prudo@linux.ibm.com> (s390)
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-03-12 07:43:57 -04:00
Paul Moore
5e729e111e selinux: avtab_init() and cond_policydb_init() return void
The avtab_init() and cond_policydb_init() functions always return
zero so mark them as returning void and update the callers not to
check for a return value.

Suggested-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-03-05 14:55:43 -05:00
Ondrej Mosnacek
34a2dab488 selinux: clean up error path in policydb_init()
Commit e0ac568de1 ("selinux: reduce the use of hard-coded hash sizes")
moved symtab initialization out of policydb_init(), but left the cleanup
of symtabs from the error path. This patch fixes the oversight.

Suggested-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-03-05 14:49:15 -05:00
Tushar Sugandhi
555d6d71d5 integrity: Remove duplicate pr_fmt definitions
The #define for formatting log messages, pr_fmt, is duplicated in the
files under security/integrity.

This change moves the definition to security/integrity/integrity.h and
removes the duplicate definitions in the other files under
security/integrity.

With this change, the messages in the following files will be prefixed
with 'integrity'.

     security/integrity/platform_certs/platform_keyring.c
     security/integrity/platform_certs/load_powerpc.c
     security/integrity/platform_certs/load_uefi.c
     security/integrity/iint.c

     e.g. "integrity: Error adding keys to platform keyring %s\n"

And the messages in the following file will be prefixed with 'ima'.

     security/integrity/ima/ima_mok.c

     e.g. "ima: Allocating IMA blacklist keyring.\n"

For the rest of the files under security/integrity, there will be no
change in the message format.

Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-28 14:32:58 -05:00
Tushar Sugandhi
72ec611c64 IMA: Add log statements for failure conditions
process_buffer_measurement() does not have log messages for failure
conditions.

This change adds a log statement in the above function.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-28 14:32:58 -05:00
Tushar Sugandhi
e2bf6814be IMA: Update KBUILD_MODNAME for IMA files to ima
The kbuild Makefile specifies object files for vmlinux in the $(obj-y)
lists. These lists depend on the kernel configuration[1].

The kbuild Makefile for IMA combines the object files for IMA into a
single object file namely ima.o. All the object files for IMA should be
combined into ima.o. But certain object files are being added to their
own $(obj-y). This results in the log messages from those modules getting
prefixed with their respective base file name, instead of "ima". This is
inconsistent with the log messages from the IMA modules that are combined
into ima.o.

This change fixes the above issue.

[1] Documentation\kbuild\makefiles.rst

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-28 14:32:58 -05:00
Stephen Smalley
e3e0b582c3 selinux: remove unused initial SIDs and improve handling
Remove initial SIDs that have never been used or are no longer used by
the kernel from its string table, which is also used to generate the
SECINITSID_* symbols referenced in code.  Update the code to
gracefully handle the fact that these can now be NULL. Stop treating
it as an error if a policy defines additional initial SIDs unknown to
the kernel.  Do not load unused initial SID contexts into the sidtab.
Fix the incorrect usage of the name from the ocontext in error
messages when loading initial SIDs since these are not presently
written to the kernel policy and are therefore always NULL.

After this change, it is possible to safely reclaim and reuse some of
the unused initial SIDs without compatibility issues.  Specifically,
unused initial SIDs that were being assigned the same context as the
unlabeled initial SID in policies can be reclaimed and reused for
another purpose, with existing policies still treating them as having
the unlabeled context and future policies having the option of mapping
them to a more specific context.  For example, this could have been
used when the infiniband labeling support was introduced to define
initial SIDs for the default pkey and endport SIDs similar to the
handling of port/netif/node SIDs rather than always using
SECINITSID_UNLABELED as the default.

The set of safely reclaimable unused initial SIDs across all known
policies is igmp_packet (13), icmp_socket (14), tcp_socket (15), kmod
(24), policy (25), and scmp_packet (26); these initial SIDs were
assigned the same context as unlabeled in all known policies including
mls.  If only considering non-mls policies (i.e. assuming that mls
users always upgrade policy with their kernels), the set of safely
reclaimable unused initial SIDs further includes file_labels (6), init
(7), sysctl_modprobe (16), and sysctl_fs (18) through sysctl_dev (23).

Adding new initial SIDs beyond SECINITSID_NUM to policy unfortunately
became a fatal error in commit 24ed7fdae6 ("selinux: use separate
table for initial SID lookup") and even before that it could cause
problems on a policy reload (collision between the new initial SID and
one allocated at runtime) ever since commit 42596eafdd ("selinux:
load the initial SIDs upon every policy load") so we cannot safely
start adding new initial SIDs to policies beyond SECINITSID_NUM (27)
until such a time as all such kernels do not need to be supported and
only those that include this commit are relevant. That is not a big
deal since we haven't added a new initial SID since 2004 (v2.6.7) and
we have plenty of unused ones we can reclaim if we truly need one.

If we want to avoid the wasted storage in initial_sid_to_string[]
and/or sidtab->isids[] for the unused initial SIDs, we could introduce
an indirection between the kernel initial SID values and the policy
initial SID values and just map the policy SID values in the ocontexts
to the kernel values during policy_load_isids(). Originally I thought
we'd do this by preserving the initial SID names in the kernel policy
and creating a mapping at load time like we do for the security
classes and permissions but that would require a new kernel policy
format version and associated changes to libsepol/checkpolicy and I'm
not sure it is justified. Simpler approach is just to create a fixed
mapping table in the kernel from the existing fixed policy values to
the kernel values. Less flexible but probably sufficient.

A separate selinux userspace change was applied in
8677ce5e8f
to enable removal of most of the unused initial SID contexts from
policies, but there is no dependency between that change and this one.
That change permits removing all of the unused initial SID contexts
from policy except for the fs and sysctl SID contexts.  The initial
SID declarations themselves would remain in policy to preserve the
values of subsequent ones but the contexts can be dropped.  If/when
the kernel decides to reuse one of them, future policies can change
the name and start assigning a context again without breaking
compatibility.

Here is how I would envision staging changes to the initial SIDs in a
compatible manner after this commit is applied:

1. At any time after this commit is applied, the kernel could choose
to reclaim one of the safely reclaimable unused initial SIDs listed
above for a new purpose (i.e. replace its NULL entry in the
initial_sid_to_string[] table with a new name and start using the
newly generated SECINITSID_name symbol in code), and refpolicy could
at that time rename its declaration of that initial SID to reflect its
new purpose and start assigning it a context going
forward. Existing/old policies would map the reclaimed initial SID to
the unlabeled context, so that would be the initial default behavior
until policies are updated. This doesn't depend on the selinux
userspace change; it will work with existing policies and userspace.

2. In 6 months or so we'll have another SELinux userspace release that
will include the libsepol/checkpolicy support for omitting unused
initial SID contexts.

3. At any time after that release, refpolicy can make that release its
minimum build requirement and drop the sid context statements (but not
the sid declarations) for all of the unused initial SIDs except for
fs and sysctl, which must remain for compatibility on policy
reload with old kernels and for compatibility with kernels that were
still using SECINITSID_SYSCTL (< 2.6.39). This doesn't depend on this
kernel commit; it will work with previous kernels as well.

4. After N years for some value of N, refpolicy decides that it no
longer cares about policy reload compatibility for kernels that
predate this kernel commit, and refpolicy drops the fs and sysctl
SID contexts from policy too (but retains the declarations).

5. After M years for some value of M, the kernel decides that it no
longer cares about compatibility with refpolicies that predate step 4
(dropping the fs and sysctl SIDs), and those two SIDs also become
safely reclaimable.  This step is optional and need not ever occur unless
we decide that the need to reclaim those two SIDs outweighs the
compatibility cost.

6. After O years for some value of O, refpolicy decides that it no
longer cares about policy load (not just reload) compatibility for
kernels that predate this kernel commit, and both kernel and refpolicy
can then start adding and using new initial SIDs beyond 27. This does
not depend on the previous change (step 5) and can occur independent
of it.

Fixes: https://github.com/SELinuxProject/selinux-kernel/issues/12
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-27 19:34:24 -05:00
Ondrej Mosnacek
e0ac568de1 selinux: reduce the use of hard-coded hash sizes
Instead allocate hash tables with just the right size based on the
actual number of elements (which is almost always known beforehand, we
just need to defer the hashtab allocation to the right time). The only
case when we don't know the size (with the current policy format) is the
new filename transitions hashtable. Here I just left the existing value.

After this patch, the time to load Fedora policy on x86_64 decreases
from 790 ms to 167 ms. If the unconfined module is removed, it decreases
from 750 ms to 122 ms. It is also likely that other operations are going
to be faster, mainly string_to_context_struct() or mls_compute_sid(),
but I didn't try to quantify that.

The memory usage of all hash table arrays increases from ~58 KB to
~163 KB (with Fedora policy on x86_64).

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-27 19:23:20 -05:00