Граф коммитов

262745 Коммитов

Автор SHA1 Сообщение Дата
Tetsuo Handa e2b8b25a67 TOMOYO: Remove redundant tasklist_lock.
rcu_read_lock() is sufficient for calling find_task_by_pid_ns()/find_task_by_vpid().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-10-12 12:15:18 +11:00
Tetsuo Handa e00fb3f7af TOMOYO: Fix domain transition failure warning.
Commit bd03a3e4 "TOMOYO: Add policy namespace support." introduced policy
namespace. But as of /sbin/modprobe is executed from initramfs/initrd, profiles
for target domain's namespace is not defined because /sbin/tomoyo-init is not
yet called.

Reported-by: Jamie Nguyen <jamie@tomoyolinux.co.uk>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-28 11:53:15 +10:00
James Morris c6cb56fc94 Merge branch 'next-hex2bin' of git://github.com/mzohar/linux-evm into next 2011-09-27 09:20:46 +10:00
Tetsuo Handa a427fd14d3 TOMOYO: Remove tomoyo_policy_memory_lock spinlock.
tomoyo_policy_lock mutex already protects it.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-26 10:46:22 +10:00
Tetsuo Handa f9732ea145 TOMOYO: Simplify garbage collector.
When TOMOYO started using garbage collector at commit 847b173e "TOMOYO: Add
garbage collector.", we waited for close() before kfree(). Thus, elements to be
kfree()d were queued up using tomoyo_gc_list list.

But it turned out that tomoyo_element_linked_by_gc() tends to choke garbage
collector when certain pattern of entries are queued.

Since garbage collector is no longer waiting for close() since commit 2e503bbb
"TOMOYO: Fix lockdep warning.", we can remove tomoyo_gc_list list and
tomoyo_element_linked_by_gc() by doing sequential processing.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-26 10:46:20 +10:00
Tetsuo Handa 778c4a4d60 TOMOYO: Fix make namespacecheck warnings.
Commit efe836ab "TOMOYO: Add built-in policy support." introduced
tomoyo_load_builtin_policy() but was by error called from nowhere.

Commit b22b8b9f "TOMOYO: Rename meminfo to stat and show more statistics."
introduced tomoyo_update_stat() but was by error not called from
tomoyo_assign_domain().

Also, mark tomoyo_io_printf() and tomoyo_path_permission() static functions,
as reported by "make namespacecheck".

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-26 10:46:19 +10:00
Mimi Zohar 8c35ad2027 target: check hex2bin result
Now that hex2bin does error checking, on error add debugging error msg.

Changelog v1 (update):
- fixed definition of 'ret'
- hex2bin now returns an int

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2011-09-21 08:27:43 -04:00
Mimi Zohar 2b3ff6319e encrypted-keys: check hex2bin result
For each hex2bin call in encrypted keys, check that the ascii hex string
is valid.  On failure, return -EINVAL.

Changelog v1:
- hex2bin now returns an int

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2011-09-20 23:26:44 -04:00
Mimi Zohar 2684bf7f29 trusted-keys: check hex2bin result
For each hex2bin call in trusted keys, check that the ascii hex string is
valid.  On failure, return -EINVAL.

Changelog v1:
- hex2bin now returns an int

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2011-09-20 23:26:05 -04:00
Mimi Zohar b78049831f lib: add error checking to hex2bin
hex2bin converts a hexadecimal string to its binary representation.
The original version of hex2bin did not do any error checking.  This
patch adds error checking and returns the result.

Changelog v1:
- removed unpack_hex_byte()
- changed return code from boolean to int

Changelog:
- use the new unpack_hex_byte()
- add __must_check compiler option (Andy Shevchenko's suggestion)
- change function API to return error checking result
  (based on Tetsuo Handa's initial patch)

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2011-09-20 23:24:44 -04:00
Tetsuo Handa 6bce98edc3 TOMOYO: Allow specifying domain transition preference.
I got an opinion that it is difficult to use exception policy's domain
transition control directives because they need to match the pathname specified
to "file execute" directives. For example, if "file execute /bin/\*\-ls\-cat"
is given, corresponding domain transition control directive needs to be like
"no_keep_domain /bin/\*\-ls\-cat from any".

If we can specify like below, it will become more convenient.

  file execute /bin/ls keep exec.realpath="/bin/ls" exec.argv[0]="ls"
  file execute /bin/cat keep exec.realpath="/bin/cat" exec.argv[0]="cat"
  file execute /bin/\*\-ls\-cat child
  file execute /usr/sbin/httpd <apache> exec.realpath="/usr/sbin/httpd" exec.argv[0]="/usr/sbin/httpd"

In above examples, "keep" works as if keep_domain is specified, "child" works
as if "no_reset_domain" and "no_initialize_domain" and "no_keep_domain" are
specified, "<apache>" causes domain transition to <apache> domain upon
successful execve() operation.

Moreover, we can also allow transition to different domains based on conditions
like below example.

  <kernel> /usr/sbin/sshd
  file execute /bin/bash <kernel> /usr/sbin/sshd //batch-session exec.argc=2 exec.argv[1]="-c"
  file execute /bin/bash <kernel> /usr/sbin/sshd //root-session task.uid=0
  file execute /bin/bash <kernel> /usr/sbin/sshd //nonroot-session task.uid!=0

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-19 10:09:59 +10:00
Stephen Rothwell cc100551b4 encrypted-keys: IS_ERR need include/err.h
Fixes this build error:

security/keys/encrypted-keys/masterkey_trusted.c: In function 'request_trusted_key':
security/keys/encrypted-keys/masterkey_trusted.c:35:2: error: implicit declaration of function 'IS_ERR'

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-15 17:37:24 -04:00
James Morris 8de6ac7f58 Merge branch 'next-evm' of git://github.com/mzohar/linux-evm into next 2011-09-15 09:53:38 +10:00
Tetsuo Handa 843d183cdd TOMOYO: Bump version.
Tell userland tools that this is TOMOYO 2.5.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-15 08:14:21 +10:00
Dmitry Kasatkin fb788d8b98 evm: clean verification status
When allocating from slab, initialization is done the first time in
init_once() and subsequently on free.  Because evm_status was not
re-initialized on free, evm_verify_hmac() skipped verifications.

This patch re-initializes evm_status.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:52 -04:00
Mimi Zohar 566be59ab8 evm: permit mode bits to be updated
Before permitting 'security.evm' to be updated, 'security.evm' must
exist and be valid.  In the case that there are no existing EVM protected
xattrs, it is safe for posix acls to update the mode bits.

To differentiate between no 'security.evm' xattr and no xattrs used to
calculate 'security.evm', this patch defines INTEGRITY_NOXATTR.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:52 -04:00
Mimi Zohar bf6d0f5dcd evm: posix acls modify i_mode
The posix xattr acls are 'system' prefixed, which normally would not
affect security.evm.  An interesting side affect of writing posix xattr
acls is their modifying of the i_mode, which is included in security.evm.

This patch updates security.evm when posix xattr acls are written.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:51 -04:00
Mimi Zohar a924ce0b35 evm: limit verifying current security.evm integrity
evm_protect_xattr unnecessarily validates the current security.evm
integrity, before updating non-evm protected extended attributes
and other file metadata. This patch limits validating the current
security.evm integrity to evm protected metadata.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:51 -04:00
Mimi Zohar fb88c2b6cb evm: fix security/security_old_init_security return code
security_inode_init_security previously returned -EOPNOTSUPP, for S_PRIVATE
inodes, and relied on the callers to change it to 0.  As the callers do not
change the return code anymore, return 0, intead of -EOPNOTSUPP.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:50 -04:00
Mimi Zohar 1d714057ef evm: remove TCG_TPM dependency
All tristates selected by EVM(boolean) are forced to be builtin, except
in the TCG_TPM(tristate) dependency case. Arnaud Lacombe summarizes the
Kconfig bug as, "So it would seem direct dependency state influence the
state of reverse dependencies.."  For a detailed explanation, refer to
Arnaud Lacombe's posting http://lkml.org/lkml/2011/8/23/498.

With the "encrypted-keys: remove trusted-keys dependency" patch, EVM
can now be built without a dependency on TCG_TPM.  The trusted-keys
dependency requires trusted-keys to either be builtin or not selected.
This dependency will prevent the boolean/tristate mismatch from
occuring.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>,
             Randy Dunlap <rdunlap@xenotimenet>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:24:49 -04:00
Mimi Zohar 982e617a31 encrypted-keys: remove trusted-keys dependency
Encrypted keys are decrypted/encrypted using either a trusted-key or,
for those systems without a TPM, a user-defined key.  This patch
removes the trusted-keys and TCG_TPM dependencies.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:23:49 -04:00
Mimi Zohar 61cf45d019 encrypted-keys: create encrypted-keys directory
Move all files associated with encrypted keys to keys/encrypted-keys.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2011-09-14 15:22:26 -04:00
Tetsuo Handa a8f7640963 TOMOYO: Avoid race when retrying "file execute" permission check.
There was a race window that the pathname which is subjected to "file execute"
permission check when retrying via supervisor's decision because the pathname
was recalculated upon retry. Though, there is an inevitable race window even
without supervisor, for we have to calculate the symbolic link's pathname from
"struct linux_binprm"->filename rather than from "struct linux_binprm"->file
because we cannot back calculate the symbolic link's pathname from the
dereferenced pathname.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-14 08:27:07 +10:00
Tetsuo Handa 731d37aa70 TOMOYO: Allow domain transition without execve().
To be able to split permissions for Apache's CGI programs which are executed
without execve(), add special domain transition which is performed by writing
a TOMOYO's domainname to /sys/kernel/security/tomoyo/self_domain interface.

This is an API for TOMOYO-aware userland applications. However, since I expect
TOMOYO and other LSM modules to run in parallel, this patch does not use
/proc/self/attr/ interface in order to avoid conflicts with other LSM modules
when it became possible to run multiple LSM modules in parallel.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-14 08:27:06 +10:00
Tetsuo Handa 1f067a682a TOMOYO: Allow controlling generation of access granted logs for per an entry basis.
Add per-entry flag which controls generation of grant logs because Xen and KVM
issues ioctl requests so frequently. For example,

  file ioctl /dev/null 0x5401 grant_log=no

will suppress /sys/kernel/security/tomoyo/audit even if preference says
grant_log=yes .

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-14 08:27:06 +10:00
Tetsuo Handa 059d84dbb3 TOMOYO: Add socket operation restriction support.
This patch adds support for permission checks for PF_INET/PF_INET6/PF_UNIX
socket's bind()/listen()/connect()/send() operations.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-14 08:27:05 +10:00
Tetsuo Handa d58e0da854 TOMOYO: Add environment variable name restriction support.
This patch adds support for checking environment variable's names.
Although TOMOYO already provides ability to check argv[]/envp[] passed to
execve() requests,

  file execute /bin/sh exec.envp["LD_LIBRARY_PATH"]="bar"

will reject execution of /bin/sh if environment variable LD_LIBRARY_PATH is not
defined. To grant execution of /bin/sh if LD_LIBRARY_PATH is not defined,
administrators have to specify like

  file execute /bin/sh exec.envp["LD_LIBRARY_PATH"]="/system/lib"
  file execute /bin/sh exec.envp["LD_LIBRARY_PATH"]=NULL

. Since there are many environment variables whereas conditional checks are
applied as "&&", it is difficult to cover all combinations. Therefore, this
patch supports conditional checks that are applied as "||", by specifying like

  file execute /bin/sh
  misc env LD_LIBRARY_PATH exec.envp["LD_LIBRARY_PATH"]="/system/lib"

which means "grant execution of /bin/sh if environment variable is not defined
or is defined and its value is /system/lib".

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-14 08:27:05 +10:00
James Morris 5dbe3040c7 security: sparse fix: Move security_fixup_op to security.h
Fix sparse warning by moving declaraion to global header.

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:33 -07:00
James Morris 7b98a5857c selinux: sparse fix: fix several warnings in the security server code
Fix several sparse warnings in the SELinux security server code.

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:32 -07:00
James Morris 0ff53f5ddb selinux: sparse fix: include selinux.h in exports.c
Fix warning:
security/selinux/exports.c:18:6: warning: symbol 'selinux_is_enabled' was not declared. Should it be static?

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:32 -07:00
James Morris 6a3fbe8117 selinux: sparse fix: fix warnings in netlink code
Fix sparse warnings in SELinux Netlink code.

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:31 -07:00
James Morris ad3fa08c4f selinux: sparse fix: eliminate warnings for selinuxfs
Fixes several sparse warnings for selinuxfs.c

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:30 -07:00
James Morris d5813a5718 ima: sparse fix: include linux/ima.h in ima_main.c
Fixes sparse warnings:
security/integrity/ima/ima_main.c:105:6: warning: symbol 'ima_file_free' was not declared. Should it be static?
security/integrity/ima/ima_main.c:167:5: warning: symbol 'ima_file_mmap' was not declared. Should it be static?
security/integrity/ima/ima_main.c:192:5: warning: symbol 'ima_bprm_check' was not declared. Should it be static?
security/integrity/ima/ima_main.c:211:5: warning: symbol 'ima_file_check' was not declared. Should it be static?

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:30 -07:00
James Morris b97e145202 ima: sparse fix: make ima_open_policy static
Fixes sparse warning:
security/integrity/ima/ima_fs.c:290:5: warning: symbol 'ima_open_policy' was not declared. Should it be static?

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:29 -07:00
James Morris cc7db09952 apparmor: sparse fix: include procattr.h in procattr.c
Fix sparse warnings:
security/apparmor/procattr.c:35:5: warning: symbol 'aa_getprocattr' was not declared. Should it be static?
security/apparmor/procattr.c:113:5: warning: symbol 'aa_setprocattr_changehat' was not declared. Should it be static?
security/apparmor/procattr.c:158:5: warning: symbol 'aa_setprocattr_changeprofile' was not declared. Should it be static?
security/apparmor/procattr.c:166:5: warning: symbol 'aa_setprocattr_permipc' was not declared. Should it be static?

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: John Johansen <john.johansen@canonical.com>
2011-09-09 16:56:29 -07:00
James Morris 7ee95850ba apparmor: sparse fix: rename shadowed variables in policy_unpack.c
Fix the following warnings:

security/apparmor/policy_unpack.c:384:35: warning: symbol 'size' shadows an earlier one
security/apparmor/policy_unpack.c:370:24: originally declared here
security/apparmor/policy_unpack.c:443:29: warning: symbol 'tmp' shadows an earlier one
security/apparmor/policy_unpack.c:434:21: originally declared here

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: John Johansen <john.johansen@canonical.com>
2011-09-09 16:56:28 -07:00
James Morris 32c3df631b apparmor: sparse fix: add apparmor.h to lib.c
Fix the following sparse warnings:
security/apparmor/lib.c:37:6: warning: symbol 'aa_split_fqname' was not declared. Should it be static?
security/apparmor/lib.c:63:6: warning: symbol 'aa_info_message' was not declared. Should it be static?
security/apparmor/lib.c:83:6: warning: symbol 'kvmalloc' was not declared. Should it be static?
security/apparmor/lib.c:123:6: warning: symbol 'kvfree' was not declared. Should it be static?

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:28 -07:00
James Morris 33f8bf5880 apparmor: sparse fix: include ipc.h
Include ipc.h to eliminate sparse warnings.

security/apparmor/ipc.c:61:5: warning: symbol 'aa_may_ptrace' was not declared. Should it be static?
security/apparmor/ipc.c:83:5: warning: symbol 'aa_ptrace' was not declared. Should it be static

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: John Johansen <john.johansen@canonical.com>
2011-09-09 16:56:27 -07:00
James Morris 58982b7483 selinux: sparse fix: declare selinux_disable() in security.h
Sparse fix: declare selinux_disable() in security.h

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:26 -07:00
James Morris cc59a582d6 selinux: sparse fix: move selinux_complete_init
Sparse fix: move selinux_complete_init

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:26 -07:00
James Morris 56a4ca9961 selinux: sparse fix: make selinux_secmark_refcount static
Sparse fix: make selinux_secmark_refcount  static.

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:25 -07:00
James Morris 3417d8d5d4 apparmor: sparse fix: make aa_create_aafs static
Sparse fix: make aa_create_aafs static.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: John Johansen <john.johansen@canonical.com>
2011-09-09 16:56:25 -07:00
James Morris 4892722e06 integrity: sparse fix: move iint_initialized to integrity.h
Sparse fix: move iint_initialized to integrity.h

Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:56:24 -07:00
rongqing.li@windriver.com fc9ff9b7e3 security: Fix a typo
Fix a typo.

Signed-off-by: Roy.Li <rongqing.li@windriver.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:40:31 -07:00
Tetsuo Handa 852584157c TOMOYO: Fix incorrect enforce mode.
In tomoyo_get_mode() since 2.6.36, CONFIG::file::execute was by error used in
place of CONFIG::file if CONFIG::file::execute was set to other than default.
As a result, enforcing mode was not applied in a way documentation says.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-09-09 16:08:48 -07:00
Stefan Berger 403d1d0319 tpm: suppress durations sysfs output if not read
Suppress the output in the 'durations' sysfs entry if they were not read
during driver initialization. This is similar to other sysfs entries
that return nothing if for some reason sending the commands to the TPM
fails.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-24 09:30:08 +10:00
Axel Lin 8ad346c62a CRED: fix build error due to 'tgcred' undeclared
This patch adds CONFIG_KEYS guard for tgcred to fix below build error
if CONFIG_KEYS is not configured.

  CC      kernel/cred.o
kernel/cred.c: In function 'prepare_kernel_cred':
kernel/cred.c:657: error: 'tgcred' undeclared (first use in this function)
kernel/cred.c:657: error: (Each undeclared identifier is reported only once
kernel/cred.c:657: error: for each function it appears in.)
make[1]: *** [kernel/cred.o] Error 1
make: *** [kernel] Error 2

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 18:22:28 +10:00
David Howells 0c061b5707 KEYS: Correctly destroy key payloads when their keytype is removed
unregister_key_type() has code to mark a key as dead and make it unavailable in
one loop and then destroy all those unavailable key payloads in the next loop.
However, the loop to mark keys dead renders the key undetectable to the second
loop by changing the key type pointer also.

Fix this by the following means:

 (1) The key code has two garbage collectors: one deletes unreferenced keys and
     the other alters keyrings to delete links to old dead, revoked and expired
     keys.  They can end up holding each other up as both want to scan the key
     serial tree under spinlock.  Combine these into a single routine.

 (2) Move the dead key marking, dead link removal and dead key removal into the
     garbage collector as a three phase process running over the three cycles
     of the normal garbage collection procedure.  This is tracked by the
     KEY_GC_REAPING_DEAD_1, _2 and _3 state flags.

     unregister_key_type() then just unlinks the key type from the list, wakes
     up the garbage collector and waits for the third phase to complete.

 (3) Downgrade the key types sem in unregister_key_type() once it has deleted
     the key type from the list so that it doesn't block the keyctl() syscall.

 (4) Dead keys that cannot be simply removed in the third phase have their
     payloads destroyed with the key's semaphore write-locked to prevent
     interference by the keyctl() syscall.  There should be no in-kernel users
     of dead keys of that type by the point of unregistration, though keyctl()
     may be holding a reference.

 (5) Only perform timer recalculation in the GC if the timer actually expired.
     If it didn't, we'll get another cycle when it goes off - and if the key
     that actually triggered it has been removed, it's not a problem.

 (6) Only garbage collect link if the timer expired or if we're doing dead key
     clean up phase 2.

 (7) As only key_garbage_collector() is permitted to use rb_erase() on the key
     serial tree, it doesn't need to revalidate its cursor after dropping the
     spinlock as the node the cursor points to must still exist in the tree.

 (8) Drop the spinlock in the GC if there is contention on it or if we need to
     reschedule.  After dealing with that, get the spinlock again and resume
     scanning.

This has been tested in the following ways:

 (1) Run the keyutils testsuite against it.

 (2) Using the AF_RXRPC and RxKAD modules to test keytype removal:

     Load the rxrpc_s key type:

	# insmod /tmp/af-rxrpc.ko
	# insmod /tmp/rxkad.ko

     Create a key (http://people.redhat.com/~dhowells/rxrpc/listen.c):

	# /tmp/listen &
	[1] 8173

     Find the key:

	# grep rxrpc_s /proc/keys
	091086e1 I--Q--     1 perm 39390000     0     0 rxrpc_s   52:2

     Link it to a session keyring, preferably one with a higher serial number:

	# keyctl link 0x20e36251 @s

     Kill the process (the key should remain as it's linked to another place):

	# fg
	/tmp/listen
	^C

     Remove the key type:

	rmmod rxkad
	rmmod af-rxrpc

     This can be made a more effective test by altering the following part of
     the patch:

	if (unlikely(gc_state & KEY_GC_REAPING_DEAD_2)) {
		/* Make sure everyone revalidates their keys if we marked a
		 * bunch as being dead and make sure all keyring ex-payloads
		 * are destroyed.
		 */
		kdebug("dead sync");
		synchronize_rcu();

     To call synchronize_rcu() in GC phase 1 instead.  That causes that the
     keyring's old payload content to hang around longer until it's RCU
     destroyed - which usually happens after GC phase 3 is complete.  This
     allows the destroy_dead_key branch to be tested.

Reported-by: Benjamin Coddington <bcodding@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 09:57:37 +10:00
David Howells d199798bdf KEYS: The dead key link reaper should be non-reentrant
The dead key link reaper should be non-reentrant as it relies on global state
to keep track of where it's got to when it returns to the work queue manager to
give it some air.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 09:57:36 +10:00
David Howells b072e9bc2f KEYS: Make the key reaper non-reentrant
Make the key reaper non-reentrant by sticking it on the appropriate system work
queue when we queue it.  This will allow it to have global state and drop
locks.  It should probably be non-reentrant already as it may spend a long time
holding the key serial spinlock, and so multiple entrants can spend long
periods of time just sitting there spinning, waiting to get the lock.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 09:57:36 +10:00