Commit Graph

1058 Commits

Author SHA1 Message Date
Dan Carpenter
4303ef19c6 KEYS: Propagate error code instead of returning -EINVAL
This is from a Smatch check I'm writing.

strncpy_from_user() returns -EFAULT on error so the first change just
silences a warning but doesn't change how the code works.

The other change is a bug fix because install_thread_keyring_to_cred()
can return a variety of errors such as -EINVAL, -EEXIST, -ENOMEM or
-EKEYREVOKED.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-06-27 07:02:34 -07:00
Oleg Nesterov
dd98acf747 keyctl_session_to_parent(): use thread_group_empty() to check singlethreadness
No functional changes.

keyctl_session_to_parent() is the only user of signal->count which needs
the correct value.  Change it to use thread_group_empty() instead, this
must be strictly equivalent under tasklist, and imho looks better.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:47 -07:00
Oleg Nesterov
685bfd2c48 umh: creds: convert call_usermodehelper_keys() to use subprocess_info->init()
call_usermodehelper_keys() uses call_usermodehelper_setkeys() to change
subprocess_info->cred in advance.  Now that we have info->init() we can
change this code to set tgcred->session_keyring in context of execing
kernel thread.

Note: since currently call_usermodehelper_keys() is never called with
UMH_NO_WAIT, call_usermodehelper_keys()->key_get() and umh_keys_cleanup()
are not really needed, we could rely on install_session_keyring_to_cred()
which does key_get() on success.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:45 -07:00
Alexey Dobriyan
4be929be34 kernel-wide: replace USHORT_MAX, SHORT_MAX and SHORT_MIN with USHRT_MAX, SHRT_MAX and SHRT_MIN
- C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not
  USHORT_MAX/SHORT_MAX/SHORT_MIN.

- Make SHRT_MIN of type s16, not int, for consistency.

[akpm@linux-foundation.org: fix drivers/dma/timb_dma.c]
[akpm@linux-foundation.org: fix security/keys/keyring.c]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:02 -07:00
Al Viro
e8c2625599 switch selinux delayed superblock handling to iterate_supers()
... kill their private list, while we are at it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-21 18:31:17 -04:00
NeilBrown
db1afffab0 kref: remove kref_set
Of the three uses of kref_set in the kernel:

 One really should be kref_put as the code is letting go of a
    reference,
 Two really should be kref_init because the kref is being
    initialised.

This suggests that making kref_set available encourages bad code.
So fix the three uses and remove kref_set completely.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-21 09:37:29 -07:00
Dan Carpenter
4d09ec0f70 KEYS: Return more accurate error codes
We were using the wrong variable here so the error codes weren't being returned
properly.  The original code returns -ENOKEY.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-18 08:50:55 +10:00
Tetsuo Handa
c80901f275 LSM: Add __init to fixup function.
register_security() became __init function.
So do verify() and security_fixup_ops().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-17 09:27:20 +10:00
Tetsuo Handa
7762fbfffd TOMOYO: Add pathname grouping support.
This patch adds pathname grouping support, which is useful for grouping
pathnames that cannot be represented using /\{dir\}/ pattern.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-17 09:25:57 +10:00
Mimi Zohar
ba0c1709f4 ima: remove ACPI dependency
The ACPI dependency moved to the TPM, where it belongs.  Although
IMA per-se does not require access to the bios measurement log,
verifying the IMA boot aggregate does, which requires ACPI.

This patch prereq's 'TPM: ACPI/PNP dependency removal'
http://lkml.org/lkml/2010/5/4/378.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Reported-by: Jean-Christophe Dubois <jcd@tribudubois.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Tested-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-17 09:21:58 +10:00
Julia Lawall
b3139bbc52 security/selinux/ss: Use kstrdup
Use kstrdup when the goal of an allocation is copy a string into the
allocated region.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to;
expression flag,E1,E2;
statement S;
@@

-  to = kmalloc(strlen(from) + 1,flag);
+  to = kstrdup(from, flag);
   ... when != \(from = E1 \| to = E1 \)
   if (to==NULL || ...) S
   ... when != \(from = E2 \| to = E2 \)
-  strcpy(to, from);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-17 09:00:27 +10:00
Tetsuo Handa
9e4b50e937 TOMOYO: Use stack memory for pending entry.
Use stack memory for pending entry to reduce kmalloc() which will be kfree()d.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-10 17:59:02 +10:00
James Morris
83c36ccfe4 Revert "ima: remove ACPI dependency"
This reverts commit a674fa46c7.

Previous revert was a prereq.

Signed-off-by: James Morris <jmorris@namei.org>
2010-05-07 09:20:03 +10:00
David Howells
f70e2e0619 KEYS: Do preallocation for __key_link()
Do preallocation for __key_link() so that the various callers in request_key.c
can deal with any errors from this source before attempting to construct a key.
This allows them to assume that the actual linkage step is guaranteed to be
successful.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-06 22:25:02 +10:00
James Morris
043b4d40f5 Merge branch 'master' into next
Conflicts:
	security/keys/keyring.c

Resolved conflict with whitespace fix in find_keyring_by_name()

Signed-off-by: James Morris <jmorris@namei.org>
2010-05-06 22:21:04 +10:00
Tetsuo Handa
2928238142 TOMOYO: Use mutex_lock_interruptible.
Some of TOMOYO's functions may sleep after mutex_lock(). If OOM-killer selected
a process which is waiting at mutex_lock(), the to-be-killed process can't be
killed. Thus, replace mutex_lock() with mutex_lock_interruptible() so that the
to-be-killed process can immediately return from TOMOYO's functions.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-06 13:19:18 +10:00
David Howells
2b9e4688fa KEYS: Better handling of errors from construct_alloc_key()
Errors from construct_alloc_key() shouldn't just be ignored in the way they are
by construct_key_and_link().  The only error that can be ignored so is
EINPROGRESS as that is used to indicate that we've found a key and don't need
to construct one.

We don't, however, handle ENOMEM, EDQUOT or EACCES to indicate allocation
failures of one sort or another.

Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-06 10:56:55 +10:00
David Howells
553d603c8f KEYS: keyring_serialise_link_sem is only needed for keyring->keyring links
keyring_serialise_link_sem is only needed for keyring->keyring links as it's
used to prevent cycle detection from being avoided by parallel keyring
additions.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-06 10:56:52 +10:00
James Morris
0ffbe2699c Merge branch 'master' into next 2010-05-06 10:56:07 +10:00
Tetsuo Handa
4e5d6f7ec3 TOMOYO: Use GFP_NOFS rather than GFP_KERNEL.
In Ubuntu, security_path_*() hooks are exported to Unionfs. Thus, prepare for
being called from inside VFS functions because I'm not sure whether it is safe
to use GFP_KERNEL or not.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-06 00:50:43 +10:00
David Howells
896903c2f5 KEYS: call_sbin_request_key() must write lock keyrings before modifying them
call_sbin_request_key() creates a keyring and then attempts to insert a link to
the authorisation key into that keyring, but does so without holding a write
lock on the keyring semaphore.

It will normally get away with this because it hasn't told anyone that the
keyring exists yet.  The new keyring, however, has had its serial number
published, which means it can be accessed directly by that handle.

This was found by a previous patch that adds RCU lockdep checks to the code
that reads the keyring payload pointer, which includes a check that the keyring
semaphore is actually locked.

Without this patch, the following command:

	keyctl request2 user b a @s

will provoke the following lockdep warning is displayed in dmesg:

	===================================================
	[ INFO: suspicious rcu_dereference_check() usage. ]
	---------------------------------------------------
	security/keys/keyring.c:727 invoked rcu_dereference_check() without protection!

	other info that might help us debug this:

	rcu_scheduler_active = 1, debug_locks = 0
	2 locks held by keyctl/2076:
	 #0:  (key_types_sem){.+.+.+}, at: [<ffffffff811a5b29>] key_type_lookup+0x1c/0x71
	 #1:  (keyring_serialise_link_sem){+.+.+.}, at: [<ffffffff811a6d1e>] __key_link+0x4d/0x3c5

	stack backtrace:
	Pid: 2076, comm: keyctl Not tainted 2.6.34-rc6-cachefs #54
	Call Trace:
	 [<ffffffff81051fdc>] lockdep_rcu_dereference+0xaa/0xb2
	 [<ffffffff811a6d1e>] ? __key_link+0x4d/0x3c5
	 [<ffffffff811a6e6f>] __key_link+0x19e/0x3c5
	 [<ffffffff811a5952>] ? __key_instantiate_and_link+0xb1/0xdc
	 [<ffffffff811a59bf>] ? key_instantiate_and_link+0x42/0x5f
	 [<ffffffff811aa0dc>] call_sbin_request_key+0xe7/0x33b
	 [<ffffffff8139376a>] ? mutex_unlock+0x9/0xb
	 [<ffffffff811a5952>] ? __key_instantiate_and_link+0xb1/0xdc
	 [<ffffffff811a59bf>] ? key_instantiate_and_link+0x42/0x5f
	 [<ffffffff811aa6fa>] ? request_key_auth_new+0x1c2/0x23c
	 [<ffffffff810aaf15>] ? cache_alloc_debugcheck_after+0x108/0x173
	 [<ffffffff811a9d00>] ? request_key_and_link+0x146/0x300
	 [<ffffffff810ac568>] ? kmem_cache_alloc+0xe1/0x118
	 [<ffffffff811a9e45>] request_key_and_link+0x28b/0x300
	 [<ffffffff811a89ac>] sys_request_key+0xf7/0x14a
	 [<ffffffff81052c0b>] ? trace_hardirqs_on_caller+0x10c/0x130
	 [<ffffffff81394fb9>] ? trace_hardirqs_on_thunk+0x3a/0x3f
	 [<ffffffff81001eeb>] system_call_fastpath+0x16/0x1b

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-05 23:50:24 +10:00
David Howells
f0641cba77 KEYS: Use RCU dereference wrappers in keyring key type code
The keyring key type code should use RCU dereference wrappers, even when it
holds the keyring's key semaphore.

Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-05 23:50:12 +10:00
Toshiyuki Okajima
cea7daa358 KEYS: find_keyring_by_name() can gain access to a freed keyring
find_keyring_by_name() can gain access to a keyring that has had its reference
count reduced to zero, and is thus ready to be freed.  This then allows the
dead keyring to be brought back into use whilst it is being destroyed.

The following timeline illustrates the process:

|(cleaner)                           (user)
|
| free_user(user)                    sys_keyctl()
|  |                                  |
|  key_put(user->session_keyring)     keyctl_get_keyring_ID()
|  ||	//=> keyring->usage = 0        |
|  |schedule_work(&key_cleanup_task)   lookup_user_key()
|  ||                                   |
|  kmem_cache_free(,user)               |
|  .                                    |[KEY_SPEC_USER_KEYRING]
|  .                                    install_user_keyrings()
|  .                                    ||
| key_cleanup() [<= worker_thread()]    ||
|  |                                    ||
|  [spin_lock(&key_serial_lock)]        |[mutex_lock(&key_user_keyr..mutex)]
|  |                                    ||
|  atomic_read() == 0                   ||
|  |{ rb_ease(&key->serial_node,) }     ||
|  |                                    ||
|  [spin_unlock(&key_serial_lock)]      |find_keyring_by_name()
|  |                                    |||
|  keyring_destroy(keyring)             ||[read_lock(&keyring_name_lock)]
|  ||                                   |||
|  |[write_lock(&keyring_name_lock)]    ||atomic_inc(&keyring->usage)
|  |.                                   ||| *** GET freeing keyring ***
|  |.                                   ||[read_unlock(&keyring_name_lock)]
|  ||                                   ||
|  |list_del()                          |[mutex_unlock(&key_user_k..mutex)]
|  ||                                   |
|  |[write_unlock(&keyring_name_lock)]  ** INVALID keyring is returned **
|  |                                    .
|  kmem_cache_free(,keyring)            .
|                                       .
|                                       atomic_dec(&keyring->usage)
v                                         *** DESTROYED ***
TIME

If CONFIG_SLUB_DEBUG=y then we may see the following message generated:

	=============================================================================
	BUG key_jar: Poison overwritten
	-----------------------------------------------------------------------------

	INFO: 0xffff880197a7e200-0xffff880197a7e200. First byte 0x6a instead of 0x6b
	INFO: Allocated in key_alloc+0x10b/0x35f age=25 cpu=1 pid=5086
	INFO: Freed in key_cleanup+0xd0/0xd5 age=12 cpu=1 pid=10
	INFO: Slab 0xffffea000592cb90 objects=16 used=2 fp=0xffff880197a7e200 flags=0x200000000000c3
	INFO: Object 0xffff880197a7e200 @offset=512 fp=0xffff880197a7e300

	Bytes b4 0xffff880197a7e1f0:  5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ
	  Object 0xffff880197a7e200:  6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b jkkkkkkkkkkkkkkk

Alternatively, we may see a system panic happen, such as:

	BUG: unable to handle kernel NULL pointer dereference at 0000000000000001
	IP: [<ffffffff810e61a3>] kmem_cache_alloc+0x5b/0xe9
	PGD 6b2b4067 PUD 6a80d067 PMD 0
	Oops: 0000 [#1] SMP
	last sysfs file: /sys/kernel/kexec_crash_loaded
	CPU 1
	...
	Pid: 31245, comm: su Not tainted 2.6.34-rc5-nofixed-nodebug #2 D2089/PRIMERGY
	RIP: 0010:[<ffffffff810e61a3>]  [<ffffffff810e61a3>] kmem_cache_alloc+0x5b/0xe9
	RSP: 0018:ffff88006af3bd98  EFLAGS: 00010002
	RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88007d19900b
	RDX: 0000000100000000 RSI: 00000000000080d0 RDI: ffffffff81828430
	RBP: ffffffff81828430 R08: ffff88000a293750 R09: 0000000000000000
	R10: 0000000000000001 R11: 0000000000100000 R12: 00000000000080d0
	R13: 00000000000080d0 R14: 0000000000000296 R15: ffffffff810f20ce
	FS:  00007f97116bc700(0000) GS:ffff88000a280000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
	CR2: 0000000000000001 CR3: 000000006a91c000 CR4: 00000000000006e0
	DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
	DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
	Process su (pid: 31245, threadinfo ffff88006af3a000, task ffff8800374414c0)
	Stack:
	 0000000512e0958e 0000000000008000 ffff880037f8d180 0000000000000001
	 0000000000000000 0000000000008001 ffff88007d199000 ffffffff810f20ce
	 0000000000008000 ffff88006af3be48 0000000000000024 ffffffff810face3
	Call Trace:
	 [<ffffffff810f20ce>] ? get_empty_filp+0x70/0x12f
	 [<ffffffff810face3>] ? do_filp_open+0x145/0x590
	 [<ffffffff810ce208>] ? tlb_finish_mmu+0x2a/0x33
	 [<ffffffff810ce43c>] ? unmap_region+0xd3/0xe2
	 [<ffffffff810e4393>] ? virt_to_head_page+0x9/0x2d
	 [<ffffffff81103916>] ? alloc_fd+0x69/0x10e
	 [<ffffffff810ef4ed>] ? do_sys_open+0x56/0xfc
	 [<ffffffff81008a02>] ? system_call_fastpath+0x16/0x1b
	Code: 0f 1f 44 00 00 49 89 c6 fa 66 0f 1f 44 00 00 65 4c 8b 04 25 60 e8 00 00 48 8b 45 00 49 01 c0 49 8b 18 48 85 db 74 0d 48 63 45 18 <48> 8b 04 03 49 89 00 eb 14 4c 89 f9 83 ca ff 44 89 e6 48 89 ef
	RIP  [<ffffffff810e61a3>] kmem_cache_alloc+0x5b/0xe9

This problem is that find_keyring_by_name does not confirm that the keyring is
valid before accepting it.

Skipping keyrings that have been reduced to a zero count seems the way to go.
To this end, use atomic_inc_not_zero() to increment the usage count and skip
the candidate keyring if that returns false.

The following script _may_ cause the bug to happen, but there's no guarantee
as the window of opportunity is small:

	#!/bin/sh
	LOOP=100000
	USER=dummy_user
	/bin/su -c "exit;" $USER || { /usr/sbin/adduser -m $USER; add=1; }
	for ((i=0; i<LOOP; i++))
	do
		/bin/su -c "echo '$i' > /dev/null" $USER
	done
	(( add == 1 )) && /usr/sbin/userdel -r $USER
	exit

Note that the nominated user must not be in use.

An alternative way of testing this may be:

	for ((i=0; i<100000; i++))
	do
		keyctl session foo /bin/true || break
	done >&/dev/null

as that uses a keyring named "foo" rather than relying on the user and
user-session named keyrings.

Reported-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-05 23:49:10 +10:00
David Howells
cf8304e8f3 KEYS: Fix RCU handling in key_gc_keyring()
key_gc_keyring() needs to either hold the RCU read lock or hold the keyring
semaphore if it's going to scan the keyring's list.  Given that it only needs
to read the key list, and it's doing so under a spinlock, the RCU read lock is
the thing to use.

Furthermore, the RCU check added in e7b0a61b79 is
incorrect as holding the spinlock on key_serial_lock is not grounds for
assuming a keyring's pointer list can be read safely.  Instead, a simple
rcu_dereference() inside of the previously mentioned RCU read lock is what we
want.

Reported-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-05 11:39:23 +10:00
David Howells
d9a9b4aeea KEYS: Fix an RCU warning in the reading of user keys
Fix an RCU warning in the reading of user keys:

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
security/keys/user_defined.c:202 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
1 lock held by keyctl/3637:
 #0:  (&key->sem){+++++.}, at: [<ffffffff811a80ae>] keyctl_read_key+0x9c/0xcf

stack backtrace:
Pid: 3637, comm: keyctl Not tainted 2.6.34-rc5-cachefs #18
Call Trace:
 [<ffffffff81051f6c>] lockdep_rcu_dereference+0xaa/0xb2
 [<ffffffff811aa55f>] user_read+0x47/0x91
 [<ffffffff811a80be>] keyctl_read_key+0xac/0xcf
 [<ffffffff811a8a06>] sys_keyctl+0x75/0xb7
 [<ffffffff81001eeb>] system_call_fastpath+0x16/0x1b

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-05 11:38:52 +10:00
Mimi Zohar
a674fa46c7 ima: remove ACPI dependency
The ACPI dependency moved to the TPM, where it belongs.  Although
IMA per-se does not require access to the bios measurement log,
verifying the IMA boot aggregate does, which requires ACPI.

This patch prereq's 'TPM: ACPI/PNP dependency removal'
http://lkml.org/lkml/2010/5/4/378.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Reported-by: Jean-Christophe Dubois <jcd@tribudubois.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Tested-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-05-05 10:00:06 +10:00
Stephen Smalley
fcaaade1db selinux: generalize disabling of execmem for plt-in-heap archs
On Tue, 2010-04-27 at 11:47 -0700, David Miller wrote:
> From: "Tom \"spot\" Callaway" <tcallawa@redhat.com>
> Date: Tue, 27 Apr 2010 14:20:21 -0400
>
> > [root@apollo ~]$ cat /proc/2174/maps
> > 00010000-00014000 r-xp 00000000 fd:00 15466577
> >  /sbin/mingetty
> > 00022000-00024000 rwxp 00002000 fd:00 15466577
> >  /sbin/mingetty
> > 00024000-00046000 rwxp 00000000 00:00 0
> >  [heap]
>
> SELINUX probably barfs on the executable heap, the PLT is in the HEAP
> just like powerpc32 and that's why VM_DATA_DEFAULT_FLAGS has to set
> both executable and writable.
>
> You also can't remove the CONFIG_PPC32 ifdefs in selinux, since
> because of the VM_DATA_DEFAULT_FLAGS setting used still in that arch,
> the heap will always have executable permission, just like sparc does.
> You have to support those binaries forever, whether you like it or not.
>
> Let's just replace the CONFIG_PPC32 ifdef in SELINUX with CONFIG_PPC32
> || CONFIG_SPARC as in Tom's original patch and let's be done with
> this.
>
> In fact I would go through all the arch/ header files and check the
> VM_DATA_DEFAULT_FLAGS settings and add the necessary new ifdefs to the
> SELINUX code so that other platforms don't have the pain of having to
> go through this process too.

To avoid maintaining per-arch ifdefs, it seems that we could just
directly use (VM_DATA_DEFAULT_FLAGS & VM_EXEC) as the basis for deciding
whether to enable or disable these checks.   VM_DATA_DEFAULT_FLAGS isn't
constant on some architectures but instead depends on
current->personality, but we want this applied uniformly.  So we'll just
use the initial task state to determine whether or not to enable these
checks.

Signed-off-by:  Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-29 08:58:45 +10:00
Linus Torvalds
1600f9def0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  keys: don't need to use RCU in keyring_read() as semaphore is held
2010-04-27 16:26:46 -07:00
David Howells
03449cd9ea keys: the request_key() syscall should link an existing key to the dest keyring
The request_key() system call and request_key_and_link() should make a
link from an existing key to the destination keyring (if supplied), not
just from a new key to the destination keyring.

This can be tested by:

	ring=`keyctl newring fred @s`
	keyctl request2 user debug:a a
	keyctl request user debug:a $ring
	keyctl list $ring

If it says:

	keyring is empty

then it didn't work.  If it shows something like:

	1 key in keyring:
	1070462727: --alswrv     0     0 user: debug:a

then it did.

request_key() system call is meant to recursively search all your keyrings for
the key you desire, and, optionally, if it doesn't exist, call out to userspace
to create one for you.

If request_key() finds or creates a key, it should, optionally, create a link
to that key from the destination keyring specified.

Therefore, if, after a successful call to request_key() with a desination
keyring specified, you see the destination keyring empty, the code didn't work
correctly.

If you see the found key in the keyring, then it did - which is what the patch
is required for.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-27 16:26:03 -07:00
Eric Paris
cb84aa9b42 LSM Audit: rename LSM_AUDIT_NO_AUDIT to LSM_AUDIT_DATA_NONE
Most of the LSM common audit work uses LSM_AUDIT_DATA_* for the naming.
This was not so for LSM_AUDIT_NO_AUDIT which means the generic initializer
cannot be used.  This patch just renames the flag so the generic
initializer can be used.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-28 08:51:12 +10:00
David Howells
b59ec78cdc keys: don't need to use RCU in keyring_read() as semaphore is held
keyring_read() doesn't need to use rcu_dereference() to access the keyring
payload as the caller holds the key semaphore to prevent modifications
from happening whilst the data is read out.

This should solve the following warning:

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
security/keys/keyring.c:204 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
1 lock held by keyctl/2144:
 #0:  (&key->sem){+++++.}, at: [<ffffffff81177f7c>] keyctl_read_key+0x9c/0xcf

stack backtrace:
Pid: 2144, comm: keyctl Not tainted 2.6.34-rc2-cachefs #113
Call Trace:
 [<ffffffff8105121f>] lockdep_rcu_dereference+0xaa/0xb2
 [<ffffffff811762d5>] keyring_read+0x4d/0xe7
 [<ffffffff81177f8c>] keyctl_read_key+0xac/0xcf
 [<ffffffff811788d4>] sys_keyctl+0x75/0xb9
 [<ffffffff81001eeb>] system_call_fastpath+0x16/0x1b

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-28 08:37:15 +10:00
David Howells
98ec4373ba SMACK: Don't #include Ext2 headers
Don't #include Ext2 headers into Smack unnecessarily.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-27 08:46:00 +10:00
David Howells
93b4a44f3a keys: fix an RCU warning
Fix the following RCU warning:

  ===================================================
  [ INFO: suspicious rcu_dereference_check() usage. ]
  ---------------------------------------------------
  security/keys/request_key.c:116 invoked rcu_dereference_check() without protection!

This was caused by doing:

	[root@andromeda ~]# keyctl newring fred @s
	539196288
	[root@andromeda ~]# keyctl request2 user a a 539196288
	request_key: Required key not available

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-24 11:31:25 -07:00
Justin P. Mattock
c5b60b5e67 security: whitespace coding style fixes
Whitespace coding style fixes.

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-23 10:10:23 +10:00
Kees Cook
822cceec72 mmap_min_addr check CAP_SYS_RAWIO only for write
Redirecting directly to lsm, here's the patch discussed on lkml:
http://lkml.org/lkml/2010/4/22/219

The mmap_min_addr value is useful information for an admin to see without
being root ("is my system vulnerable to kernel NULL pointer attacks?") and
its setting is trivially easy for an attacker to determine by calling
mmap() in PAGE_SIZE increments starting at 0, so trying to keep it private
has no value.

Only require CAP_SYS_RAWIO if changing the value, not reading it.

Comment from Serge :

  Me, I like to write my passwords with light blue pen on dark blue
  paper, pasted on my window - if you're going to get my password, you're
  gonna get a headache.

Signed-off-by: Kees Cook <kees.cook@canonical.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-23 08:56:31 +10:00
Eric Paris
eb8dae9607 IMA: include the word IMA in printk messages
As an example IMA emits a warning when it can't find a TPM chip:

"No TPM chip found, activating TPM-bypass!"

This patch prefaces that message with IMA so we know what subsystem is
bypassing the TPM.  Do this for all pr_info and pr_err messages.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-23 08:47:53 +10:00
Dan Carpenter
b338cc8207 security: testing the wrong variable in create_by_name()
There is a typo here.  We should be testing "*dentry" instead of
"dentry".  If "*dentry" is an ERR_PTR, it gets dereferenced in either
mkdir() or create() which would cause an OOPs.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-22 21:17:41 +10:00
Eric Paris
34c111f626 IMA: drop the word integrity in the audit message
integrity_audit_msg() uses "integrity:" in the audit message.  This
violates the (loosely defined) audit system requirements that everything be
a key=value pair and it doesn't provide additional information.  This can
be obviously gleaned from the message type.  Just drop it.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 09:58:18 +10:00
Eric Paris
2f1506cd82 IMA: use audit_log_untrusted_string rather than %s
Convert all of the places IMA calls audit_log_format with %s into
audit_log_untrusted_string().  This is going to cause them all to get
quoted, but it should make audit log injection harder.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 09:58:17 +10:00
Eric Paris
7233e3ee22 IMA: handle comments in policy
IMA policy load parser will reject any policies with a comment.  This patch
will allow the parser to just ignore lines which start with a #.  This is not
very robust.  # can ONLY be used at the very beginning of a line.  Inline
comments are not allowed.

Signed-off-by: Eric Paris
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 09:58:16 +10:00
Eric Paris
28ef4002ec IMA: handle whitespace better
IMA parser will fail if whitespace is used in any way other than a single
space.  Using a tab or even using 2 spaces in a row will result in a policy
being rejected.  This patch makes the kernel ignore whitespace a bit better.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 09:58:16 +10:00
Eric Paris
e9d393bf86 IMA: reject policies with unknown entries
Currently the ima policy load code will print what it doesn't understand
but really I think it should reject any policy it doesn't understand.  This
patch makes it so!

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 09:58:15 +10:00
Eric Paris
b9035b1fd7 IMA: set entry->action to UNKNOWN rather than hard coding
ima_parse_rule currently sets entry->action = -1 and then later tests
if (entry->action == UNKNOWN).  It is true that UNKNOWN == -1 but actually
setting it to UNKNOWN makes a lot more sense in case things change in the
future.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 09:58:14 +10:00
Eric Paris
7b62e16212 IMA: do not allow the same rule to specify the same thing twice
IMA will accept rules which specify things twice and will only pay
attention to the last one.  We should reject such rules.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 09:58:14 +10:00
Eric Paris
6ccd045630 ima: handle multiple rules per write
Currently IMA will only accept one rule per write().  This patch allows IMA to
accept writes which contain multiple rules but only processes one rule per
write.  \n is used as the delimiter between rules.  IMA will return a short
write indicating that it only accepted up to the first \n.

This allows simple userspace utilities like cat to be used to load an IMA
policy instead of needing a special userspace utility that understood 'one
write per rule'

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 09:58:13 +10:00
Eric Paris
a200005038 SELinux: return error codes on policy load failure
policy load failure always return EINVAL even if the failure was for some
other reason (usually ENOMEM).  This patch passes error codes back up the
stack where they will make their way to userspace.  This might help in
debugging future problems with policy load.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-21 08:58:49 +10:00
wzt.wzt@gmail.com
6f262d8e1a Security: Fix the comment of cap_file_mmap()
In the comment of cap_file_mmap(), replace mmap_min_addr to be dac_mmap_min_addr.

Signed-off-by: Zhitong Wang <zhitong.wangzt@alibaba-inc.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-20 08:47:11 +10:00
Stephen Smalley
6c9ff1013b SELinux: Reduce max avtab size to avoid page allocation failures
Reduce MAX_AVTAB_HASH_BITS so that the avtab allocation is an order 2
allocation rather than an order 4 allocation on x86_64.  This
addresses reports of page allocation failures:
http://marc.info/?l=selinux&m=126757230625867&w=2
https://bugzilla.redhat.com/show_bug.cgi?id=570433

Reported-by:  Russell Coker <russell@coker.com.au>
Signed-off-by:  Stephen D. Smalley <sds@tycho.nsa.gov>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-15 09:26:01 +10:00
Eric Paris
05b90496f2 security: remove dead hook acct
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:19 +10:00
Eric Paris
3011a344cd security: remove dead hook key_session_to_parent
Unused hook.  Remove.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-12 12:19:18 +10:00