linux-toradex.git/security/keys, branch v2.6.34-rc4

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32+00:00

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo 
Guess-its-ok-by: Christoph Lameter 
Cc: Ingo Molnar 
Cc: Lee Schermerhorn

security: Apply lockdep-based checking to rcu_dereference() uses

2010-02-25T09:34:52+00:00

Apply lockdep-ified RCU primitives to key_gc_keyring() and
keyring_destroy().

Cc: David Howells 
Signed-off-by: Paul E. McKenney 
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1266887105-1528-12-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar

Keys: KEYCTL_SESSION_TO_PARENT needs TIF_NOTIFY_RESUME architecture support

2009-12-16T22:27:59+00:00

As of commit ee18d64c1f632043a02e6f5ba5e045bb26a5465f ("KEYS: Add a keyctl to
install a process's session keyring on its parent [try #6]"), CONFIG_KEYS=y
fails to build on architectures that haven't implemented TIF_NOTIFY_RESUME yet:

security/keys/keyctl.c: In function 'keyctl_session_to_parent':
security/keys/keyctl.c:1312: error: 'TIF_NOTIFY_RESUME' undeclared (first use in this function)
security/keys/keyctl.c:1312: error: (Each undeclared identifier is reported only once
security/keys/keyctl.c:1312: error: for each function it appears in.)

Make KEYCTL_SESSION_TO_PARENT depend on TIF_NOTIFY_RESUME until
m68k, and xtensa have implemented it.

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: James Morris 
Acked-by: Mike Frysinger

keys: PTR_ERR return of wrong pointer in keyctl_get_security()

2009-12-16T22:23:48+00:00

Return the PTR_ERR of the correct pointer.

Signed-off-by: Roel Kluin 
Signed-off-by: Andrew Morton 
Acked-by: David Howells 
Signed-off-by: James Morris

sysctl: Drop & in front of every proc_handler.

2009-11-18T16:37:40+00:00

For consistency drop & in front of every proc_handler.  Explicity
taking the address is unnecessary and it prevents optimizations
like stubbing the proc_handlers to NULL.

Cc: Alexey Dobriyan 
Cc: Ingo Molnar 
Cc: Joe Perches 
Signed-off-by: Eric W. Biederman

sysctl security/keys: Remove dead binary sysctl support

2009-11-12T10:04:56+00:00

Now that sys_sysctl is a generic wrapper around /proc/sys  .ctl_name
and .strategy members of sysctl tables are dead code.  Remove them.

Cc: David Howells 
Signed-off-by: Eric W. Biederman

KEYS: get_instantiation_keyring() should inc the keyring refcount in all cases

2009-10-15T22:19:58+00:00

The destination keyring specified to request_key() and co. is made available to
the process that instantiates the key (the slave process started by
/sbin/request-key typically).  This is passed in the request_key_auth struct as
the dest_keyring member.

keyctl_instantiate_key and keyctl_negate_key() call get_instantiation_keyring()
to get the keyring to attach the newly constructed key to at the end of
instantiation.  This may be given a specific keyring into which a link will be
made later, or it may be asked to find the keyring passed to request_key().  In
the former case, it returns a keyring with the refcount incremented by
lookup_user_key(); in the latter case, it returns the keyring from the
request_key_auth struct - and does _not_ increment the refcount.

The latter case will eventually result in an oops when the keyring prematurely
runs out of references and gets destroyed.  The effect may take some time to
show up as the key is destroyed lazily.

To fix this, the keyring returned by get_instantiation_keyring() must always
have its refcount incremented, no matter where it comes from.

This can be tested by setting /etc/request-key.conf to:

#OP	TYPE	DESCRIPTION	CALLOUT INFO	PROGRAM ARG1 ARG2 ARG3 ...
#======	=======	===============	===============	===============================
create  *	test:*		*		|/bin/false %u %g %d %{user:_display}
negate	*	*		*		/bin/keyctl negate %k 10 @u

and then doing:

	keyctl add user _display aaaaaaaa @u
        while keyctl request2 user test:x test:x @u &&
        keyctl list @u;
        do
                keyctl request2 user test:x test:x @u;
                sleep 31;
                keyctl list @u;
        done

which will oops eventually.  Changing the negate line to have @u rather than
%S at the end is important as that forces the latter case by passing a special
keyring ID rather than an actual keyring ID.

Reported-by: Alexander Zangerl 
Signed-off-by: David Howells 
Tested-by: Alexander Zangerl 
Signed-off-by: Linus Torvalds

KEYS: Have the garbage collector set its timer for live expired keys

2009-09-23T18:03:47+00:00

The key garbage collector sets a timer to start a new collection cycle at the
point the earliest key to expire should be considered garbage.  However, it
currently only does this if the key it is considering hasn't yet expired.

If the key being considering has expired, but hasn't yet reached the collection
time then it is ignored, and won't be collected until some other key provokes a
round of collection.

Make the garbage collector set the timer for the earliest key that hasn't yet
passed its collection time, rather than the earliest key that hasn't yet
expired.

Signed-off-by: David Howells 
Signed-off-by: James Morris

KEYS: Fix garbage collector

2009-09-14T23:11:02+00:00

Fix a number of problems with the new key garbage collector:

 (1) A rogue semicolon in keyring_gc() was causing the initial count of dead
     keys to be miscalculated.

 (2) A missing return in keyring_gc() meant that under certain circumstances,
     the keyring semaphore would be unlocked twice.

 (3) The key serial tree iterator (key_garbage_collector()) part of the garbage
     collector has been modified to:

     (a) Complete each scan of the keyrings before setting the new timer.

     (b) Only set the new timer for keys that have yet to expire.  This means
         that the new timer is now calculated correctly, and the gc doesn't
         get into a loop continually scanning for keys that have expired, and
         preventing other things from happening, like RCU cleaning up the old
         keyring contents.

     (c) Perform an extra scan if any keys were garbage collected in this one
     	 as a key might become garbage during a scan, and (b) could mean we
     	 don't set the timer again.

 (4) Made key_schedule_gc() take the time at which to do a collection run,
     rather than the time at which the key expires.  This means the collection
     of dead keys (key type unregistered) can happen immediately.

Signed-off-by: David Howells 
Signed-off-by: James Morris

KEYS: Unlock tasklist when exiting early from keyctl_session_to_parent

2009-09-14T23:10:59+00:00

When we exit early from keyctl_session_to_parent because of permissions or
because the session keyring is the same as the parent, we need to unlock the
tasklist.

The missing unlock causes the system to hang completely when using
keyctl(KEYCTL_SESSION_TO_PARENT) with a keyring shared with the parent.

Signed-off-by: Marc Dionne 
Signed-off-by: David Howells 
Signed-off-by: James Morris