Commit Graph

153 Commits

Author SHA1 Message Date
Tetsuo Handa
4d81897139 TOMOYO: Fix incomplete read of /sys/kernel/security/tomoyo/profile
Commit bd03a3e4 "TOMOYO: Add policy namespace support." forgot to set EOF flag
and forgot to print namespace at PREFERENCE line.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-08 13:13:45 +10:00
Tetsuo Handa
0f2a55d5bb TOMOYO: Update kernel-doc.
Update comments for scripts/kernel-doc and fix some of errors reported by
scripts/checkpatch.pl .

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-07-14 17:50:03 +10:00
Tetsuo Handa
97fb35e413 TOMOYO: Enable conditional ACL.
Enable conditional ACL by passing object's pointers.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-07-11 11:05:34 +10:00
Tetsuo Handa
5b636857fe TOMOYO: Allow using argv[]/envp[] of execve() as conditions.
This patch adds support for permission checks using argv[]/envp[] of execve()
request. Hooks are in the last patch of this pathset.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-07-11 11:05:33 +10:00
Tetsuo Handa
2ca9bf453b TOMOYO: Allow using executable's realpath and symlink's target as conditions.
This patch adds support for permission checks using executable file's realpath
upon execve() and symlink's target upon symlink(). Hooks are in the last patch
of this pathset.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-07-11 11:05:33 +10:00
Tetsuo Handa
8761afd49e TOMOYO: Allow using owner/group etc. of file objects as conditions.
This patch adds support for permission checks using file object's DAC
attributes (e.g. owner/group) when checking file's pathnames. Hooks for passing
file object's pointers are in the last patch of this pathset.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-07-11 11:05:32 +10:00
Tetsuo Handa
2066a36125 TOMOYO: Allow using UID/GID etc. of current thread as conditions.
This patch adds support for permission checks using current thread's UID/GID
etc. in addition to pathnames.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-07-11 11:05:32 +10:00
Tetsuo Handa
5c4274f138 TOMOYO: Remove /sys/kernel/security/tomoyo/.domain_status interface.
/sys/kernel/security/tomoyo/.domain_status can be easily emulated using
/sys/kernel/security/tomoyo/domain_policy . We can remove this interface by
updating /usr/sbin/tomoyo-setprofile utility.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-07-08 09:25:36 +10:00
Tetsuo Handa
ea50481912 TOMOYO: Fix wrong domainname in tomoyo_init_log().
Commit eadd99cc "TOMOYO: Add auditing interface." by error replaced
"struct tomoyo_request_info"->domain with tomoyo_domain().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-07-01 09:25:47 +10:00
Tetsuo Handa
3ddf17f08c TOMOYO: Cleanup header file.
Sort by alphabetic order.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-30 18:49:25 +10:00
Tetsuo Handa
7986cf28bc TOMOYO: Fix build error with CONFIG_SECURITY_TOMOYO_OMIT_USERSPACE_LOADER=y .
I forgot to add #ifndef in commit 0e4ae0e0 "TOMOYO: Make several options
configurable.", resulting

  security/built-in.o: In function `tomoyo_bprm_set_creds':
  tomoyo.c:(.text+0x4698e): undefined reference to `tomoyo_load_policy'

error.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-30 18:48:37 +10:00
James Morris
5b944a71a1 Merge branch 'linus' into next 2011-06-30 18:43:56 +10:00
Tetsuo Handa
0e4ae0e0de TOMOYO: Make several options configurable.
To be able to start using enforcing mode from the early stage of boot sequence,
this patch adds support for activating access control without calling external
policy loader program. This will be useful for systems where operations which
can lead to the hijacking of the boot sequence are needed before loading the
policy. For example, you can activate immediately after loading the fixed part
of policy which will allow only operations needed for mounting a partition
which contains the variant part of policy and verifying (e.g. running GPG
check) and loading the variant part of policy. Since you can start using
enforcing mode from the beginning, you can reduce the possibility of hijacking
the boot sequence.

This patch makes several variables configurable on build time. This patch also
adds TOMOYO_loader= and TOMOYO_trigger= kernel command line option to boot the
same kernel in two different init systems (BSD-style init and systemd).

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:22 +10:00
Tetsuo Handa
efe836ab2b TOMOYO: Add built-in policy support.
To be able to start using enforcing mode from the early stage of boot sequence,
this patch adds support for built-in policy configuration (and next patch adds
support for activating access control without calling external policy loader
program).

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:22 +10:00
Tetsuo Handa
b22b8b9fd9 TOMOYO: Rename meminfo to stat and show more statistics.
Show statistics such as last policy update time and last policy violation time
in addition to memory usage.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:22 +10:00
Tetsuo Handa
2c47ab9353 TOMOYO: Cleanup part 4.
Gather string constants to one file in order to make the object size smaller.
Use unsigned type where appropriate.
read()/write() returns ssize_t.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:21 +10:00
Tetsuo Handa
2e503bbb43 TOMOYO: Fix lockdep warning.
Currently TOMOYO holds SRCU lock upon open() and releases it upon close()
because list elements stored in the "struct tomoyo_io_buffer" instances are
accessed until close() is called. However, such SRCU usage causes lockdep to
complain about leaving the kernel with SRCU lock held.

This patch solves the warning by holding/releasing SRCU upon each
read()/write(). This patch is doing something similar to calling kfree()
without calling synchronize_srcu(), by selectively deferring kfree() by keeping
track of the "struct tomoyo_io_buffer" instances.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:21 +10:00
Tetsuo Handa
5625f2e326 TOMOYO: Change pathname for non-rename()able filesystems.
TOMOYO wants to use /proc/self/ rather than /proc/$PID/ if $PID matches current
thread's process ID in order to prevent current thread from accessing other
process's information unless needed.

But since procfs can be mounted on various locations (e.g. /proc/ /proc2/ /p/
/tmp/foo/100/p/ ), TOMOYO cannot tell that whether the numeric part in the
string returned by __d_path() represents process ID or not.

Therefore, to be able to convert from $PID to self no matter where procfs is
mounted, this patch changes pathname representations for filesystems which do
not support rename() operation (e.g. proc, sysfs, securityfs).

Examples:
  /proc/self/mounts => proc:/self/mounts
  /sys/kernel/security/ => sys:/kernel/security/
  /dev/pts/0 => devpts:/0

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:21 +10:00
Tetsuo Handa
bd03a3e4c9 TOMOYO: Add policy namespace support.
Mauras Olivier reported that it is difficult to use TOMOYO in LXC environments,
for TOMOYO cannot distinguish between environments outside the container and
environments inside the container since LXC environments are created using
pivot_root(). To address this problem, this patch introduces policy namespace.

Each policy namespace has its own set of domain policy, exception policy and
profiles, which are all independent of other namespaces. This independency
allows users to develop policy without worrying interference among namespaces.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:21 +10:00
Tetsuo Handa
32997144fd TOMOYO: Add ACL group support.
ACL group allows administrator to globally grant not only "file read"
permission but also other permissions.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:20 +10:00
Tetsuo Handa
eadd99cc85 TOMOYO: Add auditing interface.
Add /sys/kernel/security/tomoyo/audit interface. This interface generates audit
logs in the form of domain policy so that /usr/sbin/tomoyo-auditd can reuse
audit logs for appending to /sys/kernel/security/tomoyo/domain_policy
interface.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:20 +10:00
Tetsuo Handa
d5ca1725ac TOMOYO: Simplify profile structure.
Remove global preference from profile structure in order to make code simpler.

Due to this structure change, printk() warnings upon policy violation are
temporarily disabled. They will be replaced by
/sys/kernel/security/tomoyo/audit by next patch.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:20 +10:00
Tetsuo Handa
0d2171d711 TOMOYO: Rename directives.
Convert "allow_..." style directives to "file ..." style directives.
By converting to the latter style, we can pack policy like
"file read/write/execute /path/to/file".

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:20 +10:00
Tetsuo Handa
a238cf5b89 TOMOYO: Use struct for passing ACL line.
Use structure for passing ACL line, in preparation for supporting policy
namespace and conditional parameters.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:20 +10:00
Tetsuo Handa
0df7e8b8f1 TOMOYO: Cleanup part 3.
Use common structure for ACL with "struct list_head" + "atomic_t".
Use array/struct where possible.
Remove is_group from "struct tomoyo_name_union"/"struct tomoyo_number_union".
Pass "struct file"->private_data rather than "struct file".
Update some of comments.
Bring tomoyo_same_acl_head() from common.h to domain.c .
Bring tomoyo_invalid()/tomoyo_valid() from common.h to util.c .

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:19 +10:00
Tetsuo Handa
b5bc60b4ce TOMOYO: Cleanup part 2.
Update (or temporarily remove) comments.
Remove or replace some of #define lines.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:19 +10:00
Tetsuo Handa
7c75964f43 TOMOYO: Cleanup part 1.
In order to synchronize with TOMOYO 1.8's syntax,

(1) Remove special handling for allow_read/write permission.
(2) Replace deny_rewrite/allow_rewrite permission with allow_append permission.
(3) Remove file_pattern keyword.
(4) Remove allow_read permission from exception policy.
(5) Allow creating domains in enforcing mode without calling supervisor.
(6) Add permission check for opening directory for reading.
(7) Add permission check for stat() operation.
(8) Make "cat < /sys/kernel/security/tomoyo/self_domain" behave as if
    "cat /sys/kernel/security/tomoyo/self_domain".

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-29 09:31:19 +10:00
Tetsuo Handa
4e78c724d4 TOMOYO: Fix oops in tomoyo_mount_acl().
In tomoyo_mount_acl() since 2.6.36, kern_path() was called without checking
dev_name != NULL. As a result, an unprivileged user can trigger oops by issuing
mount(NULL, "/", "ext3", 0, NULL) request.
Fix this by checking dev_name != NULL before calling kern_path(dev_name).

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable@kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-14 15:18:42 +10:00
Tetsuo Handa
e77dc3460f TOMOYO: Fix wrong domainname validation.
In tomoyo_correct_domain() since 2.6.36, TOMOYO was by error validating
"<kernel>" + "/foo/\" + "/bar" when "<kernel> /foo/\* /bar" was given.
As a result, legal domainnames like "<kernel> /foo/\* /bar" are rejected.

Reported-by: Hayama Yossihiro <yossi@yedo.src.co.jp>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-05-12 11:07:21 +10:00
Tetsuo Handa
db5ca356d8 TOMOYO: Fix refcount leak in tomoyo_mount_acl().
In tomoyo_mount_acl() since 2.6.36, reference to device file (e.g. /dev/sda1)
was leaking.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-04-20 10:16:21 +10:00
James Morris
d4ab4e6a23 Merge branch 'master'; commit 'v2.6.39-rc3' into next 2011-04-19 21:32:41 +10:00
Tetsuo Handa
c0fa797ae6 TOMOYO: Fix infinite loop bug when reading /sys/kernel/security/tomoyo/audit
In tomoyo_flush(), head->r.w[0] holds pointer to string data to be printed.
But head->r.w[0] was updated only when the string data was partially
printed (because head->r.w[0] will be updated by head->r.w[1] later if
completely printed). However, regarding /sys/kernel/security/tomoyo/query ,
an additional '\0' is printed after the string data was completely printed.
But if free space for read buffer became 0 before printing the additional '\0',
tomoyo_flush() was returning without updating head->r.w[0]. As a result,
tomoyo_flush() forever reprints already printed string data.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-04-19 09:37:12 +10:00
Tetsuo Handa
e4f5f26d83 TOMOYO: Don't add / for allow_unmount permission check.
"mount --bind /path/to/file1 /path/to/file2" is legal. Therefore,
"umount /path/to/file2" is also legal. Do not automatically append trailing '/'
if pathname to be unmounted does not end with '/'.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-04-19 09:37:09 +10:00
Tetsuo Handa
2a086e5d3a TOMOYO: Fix race on updating profile's comment line.
In tomoyo_write_profile() since 2.6.34, a lock was by error missing when
replacing profile's comment line. If multiple threads attempted

  echo '0-COMMENT=comment' > /sys/kernel/security/tomoyo/profile

in parallel, garbage collector will fail to kfree() the old value.
Protect the replacement using a lock. Also, keep the old value rather than
replace with empty string when out of memory error has occurred.

Signed-off-by: Xiaochen Wang <wangxiaochen0@gmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-04-19 09:37:06 +10:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Xiaochen Wang
cfc64fd91f tomoyo: fix memory leak in tomoyo_commit_ok()
When memory used for policy exceeds the quota, tomoyo_memory_ok() return false.
In this case, tomoyo_commit_ok() must call kfree() before returning NULL.
This bug exists since 2.6.35.

Signed-off-by: Xiaochen Wang <wangxiaochen0@gmail.com>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-03-31 10:25:06 +11:00
Tetsuo Handa
eae61f3c82 TOMOYO: Fix memory leak upon file open.
In tomoyo_check_open_permission() since 2.6.36, TOMOYO was by error
recalculating already calculated pathname when checking allow_rewrite
permission. As a result, memory will leak whenever a file is opened for writing
without O_APPEND flag. Also, performance will degrade because TOMOYO is
calculating pathname regardless of profile configuration.
This patch fixes the leak and performance degrade.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2011-03-03 10:13:26 +11:00
Nick Piggin
da5029563a fs: dcache scale d_unhashed
Protect d_unhashed(dentry) condition with d_lock. This means keeping
DCACHE_UNHASHED bit in synch with hash manipulations.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:21 +11:00
Christoph Hellwig
be148247cf fs: take dcache_lock inside __d_path
All callers take dcache_lock just around the call to __d_path, so
take the lock into it in preparation of getting rid of dcache_lock.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25 21:26:12 -04:00
Tetsuo Handa
9f1c1d426b TOMOYO: Print URL information before panic().
Configuration files for TOMOYO 2.3 are not compatible with TOMOYO 2.2.
But current panic() message is too unfriendly and is confusing users.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-10-21 10:12:45 +11:00
Dan Carpenter
68eda8f590 tomoyo: cleanup. don't store bogus pointer
If domain is NULL then &domain->list is a bogus address.  Let's leave
head->r.domain NULL instead of saving an unusable pointer.

This is just a cleanup.  The current code always checks head->r.eof
before dereferencing head->r.domain.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
2010-10-21 10:12:32 +11:00
Ben Hutchings
c8da96e87d TOMOYO: Don't abuse sys_getpid(), sys_getppid()
System call entry functions sys_*() are never to be called from
general kernel code.  The fact that they aren't declared in header
files should have been a clue.  These functions also don't exist on
Alpha since it has sys_getxpid() instead.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-09-27 10:53:18 +10:00
Tetsuo Handa
484ca79c65 TOMOYO: Use pathname specified by policy rather than execve()
Commit c9e69318 "TOMOYO: Allow wildcard for execute permission." changed execute
permission and domainname to accept wildcards. But tomoyo_find_next_domain()
was using pathname passed to execve() rather than pathname specified by the
execute permission. As a result, processes were not able to transit to domains
which contain wildcards in their domainnames.

This patch passes pathname specified by the execute permission back to
tomoyo_find_next_domain() so that processes can transit to domains which
contain wildcards in their domainnames.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:38:38 +10:00
Tetsuo Handa
e6f6a4cc95 TOMOYO: Update version to 2.3.0
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:35:10 +10:00
Tetsuo Handa
7e3d199a40 TOMOYO: Fix quota check.
Commit d74725b9 "TOMOYO: Use callback for updating entries." broke
tomoyo_domain_quota_is_ok() by counting deleted entries. It needs to
count non-deleted entries.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:35:09 +10:00
Tetsuo Handa
7e2deb7ce8 TOMOYO: Explicitly set file_operations->llseek pointer.
TOMOYO does not deal offset pointer. Thus seek operation makes
no sense. Changing default seek operation from default_llseek()
to no_llseek() might break some applications. Thus, explicitly
set noop_llseek().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:34:57 +10:00
Tetsuo Handa
0849e3ba53 TOMOYO: Add missing poll() hook.
Commit 1dae08c "TOMOYO: Add interactive enforcing mode." forgot to register
poll() hook. As a result, /usr/sbin/tomoyo-queryd was doing busy loop.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:34:55 +10:00
Tetsuo Handa
e2bf69077a TOMOYO: Rename symbols.
Use shorter name in order to make it easier to fit 80 columns limit.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:34:54 +10:00
Tetsuo Handa
8e5686874b TOMOYO: Small cleanup.
Split tomoyo_write_profile() into several functions.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:34:54 +10:00
Tetsuo Handa
f23571e866 TOMOYO: Copy directly to userspace buffer.
When userspace program reads policy from /sys/kernel/security/tomoyo/
interface, TOMOYO uses line buffered mode. A line has at least one word.

Commit 006dacc "TOMOYO: Support longer pathname." changed a word's max length
from 4000 bytes to max kmalloc()able bytes. By that commit, a line's max length
changed from 8192 bytes to more than max kmalloc()able bytes.

Max number of words in a line remains finite. This patch changes the way of
buffering so that all words in a line are firstly directly copied to userspace
buffer as much as possible and are secondly queued for next read request.
Words queued are guaranteed to be valid until /sys/kernel/security/tomoyo/
interface is close()d.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:34:45 +10:00