While running fsstress tests on the NFSv4 mounted ext3 and ext4
filesystem, the following call trace was generated on the nfs
server machine.
Replace GFP_KERNEL with GFP_NOFS in ima_iint_insert() to avoid a
potential deadlock.
=================================
[ INFO: inconsistent lock state ]
2.6.31-31.el6.x86_64 #1
---------------------------------
inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
kswapd2/75 [HC0[0]:SC0[0]:HE1:SE1] takes:
(jbd2_handle){+.+.?.}, at: [<ffffffff811edd5e>] jbd2_journal_start+0xfe/0x13f
{RECLAIM_FS-ON-W} state was registered at:
[<ffffffff81091e40>] mark_held_locks+0x65/0x99
[<ffffffff81091f31>] lockdep_trace_alloc+0xbd/0xf5
[<ffffffff81126fdd>] kmem_cache_alloc+0x40/0x185
[<ffffffff812344d7>] ima_iint_insert+0x3d/0xf1
[<ffffffff812345b0>] ima_inode_alloc+0x25/0x44
[<ffffffff811484ac>] inode_init_always+0xec/0x271
[<ffffffff81148682>] alloc_inode+0x51/0xa1
[<ffffffff81148700>] new_inode+0x2e/0x94
[<ffffffff811b2f08>] ext4_new_inode+0xb8/0xdc9
[<ffffffff811be611>] ext4_create+0xcf/0x175
[<ffffffff8113e2cd>] vfs_create+0x82/0xb8
[<ffffffff8113f337>] do_filp_open+0x32c/0x9ee
[<ffffffff811309b9>] do_sys_open+0x6c/0x12c
[<ffffffff81130adc>] sys_open+0x2e/0x44
[<ffffffff81011e42>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
irq event stamp: 90371
hardirqs last enabled at (90371): [<ffffffff8112708d>]
kmem_cache_alloc+0xf0/0x185
hardirqs last disabled at (90370): [<ffffffff81127026>]
kmem_cache_alloc+0x89/0x185
softirqs last enabled at (89492): [<ffffffff81068ecf>]
__do_softirq+0x1bf/0x1eb
softirqs last disabled at (89477): [<ffffffff8101312c>] call_softirq+0x1c/0x30
other info that might help us debug this:
2 locks held by kswapd2/75:
#0: (shrinker_rwsem){++++..}, at: [<ffffffff810f98ba>] shrink_slab+0x44/0x177
#1: (&type->s_umount_key#25){++++..}, at: [<ffffffff811450ba>]
Reported-by: Muni P. Beerakam <mbeeraka@in.ibm.com>
Reported-by: Amit K. Arora <amitarora@in.ibm.com>
Cc: stable@kernel.org
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
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 <az@bond.edu.au>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Alexander Zangerl <az@bond.edu.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
lsm: Use a compressed IPv6 string format in audit events
Audit: send signal info if selinux is disabled
Audit: rearrange audit_context to save 16 bytes per struct
Audit: reorganize struct audit_watch to save 8 bytes
Ratan Nalumasu reported that in a process with many threads doing
unnecessary wakeups. Every waiting thread in the process wakes up to loop
through the children and see that the only ones it cares about are still
not ready.
Now that we have struct wait_opts we can change do_wait/__wake_up_parent
to use filtered wakeups.
We can make child_wait_callback() more clever later, right now it only
checks eligible_child().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ratan Nalumasu <rnalumasu@gmail.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Tested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
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>
Alter the ss->can_attach and ss->attach functions to be able to deal with
a whole threadgroup at a time, for use in cgroup_attach_proc. (This is a
pre-patch to cgroup-procs-writable.patch.)
Currently, new mode of the attach function can only tell the subsystem
about the old cgroup of the threadgroup leader. No subsystem currently
needs that information for each thread that's being moved, but if one were
to be added (for example, one that counts tasks within a group) this bit
would need to be reworked a bit to tell the subsystem the right
information.
[hidave.darkstar@gmail.com: fix build]
Signed-off-by: Ben Blum <bblum@google.com>
Signed-off-by: Paul Menage <menage@google.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Reviewed-by: Matt Helsley <matthltc@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently the audit subsystem prints uncompressed IPv6 addresses which not
only differs from common usage but also results in ridiculously large audit
strings which is not a good thing. This patch fixes this by simply converting
audit to always print compressed IPv6 addresses.
Old message example:
audit(1253576792.161:30): avc: denied { ingress } for
saddr=0000:0000:0000:0000:0000:0000:0000:0001 src=5000
daddr=0000:0000:0000:0000:0000:0000:0000:0001 dest=35502 netif=lo
scontext=system_u:object_r:unlabeled_t:s15:c0.c1023
tcontext=system_u:object_r:lo_netif_t:s0-s15:c0.c1023 tclass=netif
New message example:
audit(1253576792.161:30): avc: denied { ingress } for
saddr=::1 src=5000 daddr=::1 dest=35502 netif=lo
scontext=system_u:object_r:unlabeled_t:s15:c0.c1023
tcontext=system_u:object_r:lo_netif_t:s0-s15:c0.c1023 tclass=netif
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
SELinux: do not destroy the avc_cache_nodep
KEYS: Have the garbage collector set its timer for live expired keys
tpm-fixup-pcrs-sysfs-file-update
creds_are_invalid() needs to be exported for use by modules:
include/linux/cred.h: fix build
Fix trivial BUILD_BUG_ON-induced conflicts in drivers/char/tpm/tpm.c
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 <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Make all seq_operations structs const, to help mitigate against
revectoring user-triggerable function pointers.
This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'x86-txt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, intel_txt: clean up the impact on generic code, unbreak non-x86
x86, intel_txt: Handle ACPI_SLEEP without X86_TRAMPOLINE
x86, intel_txt: Fix typos in Kconfig help
x86, intel_txt: Factor out the code for S3 setup
x86, intel_txt: tboot.c needs <asm/fixmap.h>
intel_txt: Force IOMMU on for Intel TXT launch
x86, intel_txt: Intel TXT Sx shutdown support
x86, intel_txt: Intel TXT reboot/halt shutdown support
x86, intel_txt: Intel TXT boot support
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 <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
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 <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Before SELinux is disabled at boot it can create AVC entries. This patch
will flush those entries before disabling SELinux.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Move the avc_cache flushing into it's own function so it can be reused when
disabling SELinux.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
__validate_process_creds should check if selinux is actually enabled before
running tests on the selinux portion of the credentials struct.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch adds a setxattr handler to the file, directory, and symlink
inode_operations structures for sysfs. The patch uses hooks introduced in the
previous patch to handle the getting and setting of security information for
the sysfs inodes. As was suggested by Eric Biederman the struct iattr in the
sysfs_dirent structure has been replaced by a structure which contains the
iattr, secdata and secdata length to allow the changes to persist in the event
that the inode representing the sysfs_dirent is evicted. Because sysfs only
stores this information when a change is made all the optional data is moved
into one dynamically allocated field.
This patch addresses an issue where SELinux was denying virtd access to the PCI
configuration entries in sysfs. The lack of setxattr handlers for sysfs
required that a single label be assigned to all entries in sysfs. Granting virtd
access to every entry in sysfs is not an acceptable solution so fine grained
labeling of sysfs is required such that individual entries can be labeled
appropriately.
[sds: Fixed compile-time warnings, coding style, and setting of inode security init flags.]
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch introduces three new hooks. The inode_getsecctx hook is used to get
all relevant information from an LSM about an inode. The inode_setsecctx is
used to set both the in-core and on-disk state for the inode based on a context
derived from inode_getsecctx.The final hook inode_notifysecctx will notify the
LSM of a change for the in-core state of the inode in question. These hooks are
for use in the labeled NFS code and addresses concerns of how to set security
on an inode in a multi-xattr LSM. For historical reasons Stephen Smalley's
explanation of the reason for these hooks is pasted below.
Quote Stephen Smalley
inode_setsecctx: Change the security context of an inode. Updates the
in core security context managed by the security module and invokes the
fs code as needed (via __vfs_setxattr_noperm) to update any backing
xattrs that represent the context. Example usage: NFS server invokes
this hook to change the security context in its incore inode and on the
backing file system to a value provided by the client on a SETATTR
operation.
inode_notifysecctx: Notify the security module of what the security
context of an inode should be. Initializes the incore security context
managed by the security module for this inode. Example usage: NFS
client invokes this hook to initialize the security context in its
incore inode to the value provided by the server for the file when the
server returned the file's attributes to the client.
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
- As ima_counts_put() may be called after the inode has been freed,
verify that the inode is not NULL, before dereferencing it.
- Maintain the IMA file counters in may_open() properly, decrementing
any counter increments on subsequent errors.
Reported-by: Ciprian Docan <docan@eden.rutgers.edu>
Reported-by: J.R. Okajima <hooanon05@yahoo.co.jp>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com
Signed-off-by: James Morris <jmorris@namei.org>
Add a keyctl to install a process's session keyring onto its parent. This
replaces the parent's session keyring. Because the COW credential code does
not permit one process to change another process's credentials directly, the
change is deferred until userspace next starts executing again. Normally this
will be after a wait*() syscall.
To support this, three new security hooks have been provided:
cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
the blank security creds and key_session_to_parent() - which asks the LSM if
the process may replace its parent's session keyring.
The replacement may only happen if the process has the same ownership details
as its parent, and the process has LINK permission on the session keyring, and
the session keyring is owned by the process, and the LSM permits it.
Note that this requires alteration to each architecture's notify_resume path.
This has been done for all arches barring blackfin, m68k* and xtensa, all of
which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the
replacement to be performed at the point the parent process resumes userspace
execution.
This allows the userspace AFS pioctl emulation to fully emulate newpag() and
the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
alter the parent process's PAG membership. However, since kAFS doesn't use
PAGs per se, but rather dumps the keys into the session keyring, the session
keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
the newpag flag.
This can be tested with the following program:
#include <stdio.h>
#include <stdlib.h>
#include <keyutils.h>
#define KEYCTL_SESSION_TO_PARENT 18
#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)
int main(int argc, char **argv)
{
key_serial_t keyring, key;
long ret;
keyring = keyctl_join_session_keyring(argv[1]);
OSERROR(keyring, "keyctl_join_session_keyring");
key = add_key("user", "a", "b", 1, keyring);
OSERROR(key, "add_key");
ret = keyctl(KEYCTL_SESSION_TO_PARENT);
OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");
return 0;
}
Compiled and linked with -lkeyutils, you should see something like:
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
355907932 --alswrv 4043 -1 \_ keyring: _uid.4043
[dhowells@andromeda ~]$ /tmp/newpag
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
1055658746 --alswrv 4043 4043 \_ user: a
[dhowells@andromeda ~]$ /tmp/newpag hello
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: hello
340417692 --alswrv 4043 4043 \_ user: a
Where the test program creates a new session keyring, sticks a user key named
'a' into it and then installs it on its parent.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
