__d_path() API is asking for trouble and in case of apparmor d_namespace_path()
getting just that. The root cause is that when __d_path() misses the root
it had been told to look for, it stores the location of the most remote ancestor
in *root. Without grabbing references. Sure, at the moment of call it had
been pinned down by what we have in *path. And if we raced with umount -l, we
could have very well stopped at vfsmount/dentry that got freed as soon as
prepend_path() dropped vfsmount_lock.
It is safe to compare these pointers with pre-existing (and known to be still
alive) vfsmount and dentry, as long as all we are asking is "is it the same
address?". Dereferencing is not safe and apparmor ended up stepping into
that. d_namespace_path() really wants to examine the place where we stopped,
even if it's not connected to our namespace. As the result, it looked
at ->d_sb->s_magic of a dentry that might've been already freed by that point.
All other callers had been careful enough to avoid that, but it's really
a bad interface - it invites that kind of trouble.
The fix is fairly straightforward, even though it's bigger than I'd like:
* prepend_path() root argument becomes const.
* __d_path() is never called with NULL/NULL root. It was a kludge
to start with. Instead, we have an explicit function - d_absolute_root().
Same as __d_path(), except that it doesn't get root passed and stops where
it stops. apparmor and tomoyo are using it.
* __d_path() returns NULL on path outside of root. The main
caller is show_mountinfo() and that's precisely what we pass root for - to
skip those outside chroot jail. Those who don't want that can (and do)
use d_path().
* __d_path() root argument becomes const. Everyone agrees, I hope.
* apparmor does *NOT* try to use __d_path() or any of its variants
when it sees that path->mnt is an internal vfsmount. In that case it's
definitely not mounted anywhere and dentry_path() is exactly what we want
there. Handling of sysctl()-triggered weirdness is moved to that place.
* if apparmor is asked to do pathname relative to chroot jail
and __d_path() tells it we it's not in that jail, the sucker just calls
d_absolute_path() instead. That's the other remaining caller of __d_path(),
BTW.
* seq_path_root() does _NOT_ return -ENAMETOOLONG (it's stupid anyway -
the normal seq_file logics will take care of growing the buffer and redoing
the call of ->show() just fine). However, if it gets path not reachable
from root, it returns SEQ_SKIP. The only caller adjusted (i.e. stopped
ignoring the return value as it used to do).
Reviewed-by: John Johansen <john.johansen@canonical.com>
ACKed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Commit 17fcfbd9 "TOMOYO: Add interactive enforcing mode." introduced ability
to query access decision using userspace programs. It was using global PID for
reaching policy configuration of the process. However, use of PID returns stale
policy configuration when the process's subjective credentials and objective
credentials differ. Fix this problem by allowing reaching policy configuration
via query id.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
* 'next' of git://selinuxproject.org/~jmorris/linux-security: (95 commits)
TOMOYO: Fix incomplete read after seek.
Smack: allow to access /smack/access as normal user
TOMOYO: Fix unused kernel config option.
Smack: fix: invalid length set for the result of /smack/access
Smack: compilation fix
Smack: fix for /smack/access output, use string instead of byte
Smack: domain transition protections (v3)
Smack: Provide information for UDS getsockopt(SO_PEERCRED)
Smack: Clean up comments
Smack: Repair processing of fcntl
Smack: Rule list lookup performance
Smack: check permissions from user space (v2)
TOMOYO: Fix quota and garbage collector.
TOMOYO: Remove redundant tasklist_lock.
TOMOYO: Fix domain transition failure warning.
TOMOYO: Remove tomoyo_policy_memory_lock spinlock.
TOMOYO: Simplify garbage collector.
TOMOYO: Fix make namespacecheck warnings.
target: check hex2bin result
encrypted-keys: check hex2bin result
...
Commit f23571e8 "TOMOYO: Copy directly to userspace buffer." introduced
tomoyo_flush() that flushes data to be read as soon as possible.
tomoyo_select_domain() (which is called by write()) enqueues data which meant
to be read by next read(), but previous read()'s read buffer's size was not
cleared. As a result, since 2.6.36, sequence like
char *cp = "select global-pid=1\n";
read(fd, buf1, sizeof(buf1));
write(fd, cp, strlen(cp));
read(fd, buf2, sizeof(buf2));
causes enqueued data to be flushed to buf1 rather than buf2.
Fix this bug by clearing read buffer's size upon write() request.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
CONFIG_SECURITY_TOMOYO_MAX_{ACCEPT_ENTRY,AUDIT_LOG} introduced by commit
0e4ae0e0 "TOMOYO: Make several options configurable." were by error not used.
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
Commit 059d84db "TOMOYO: Add socket operation restriction support" and
commit 731d37aa "TOMOYO: Allow domain transition without execve()." forgot to
update tomoyo_domain_quota_is_ok() and tomoyo_del_acl() which results in
incorrect quota counting and memory leak.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
daemonize() is only needed when a user-space task does kernel_thread().
tomoyo_gc_thread() is kthread_create()'ed and thus it doesn't need
the soon-to-be-deprecated daemonize().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: James Morris <jmorris@namei.org>
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>
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>
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>
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>
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>
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>
/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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
