SELinux has long been calling wake_up_interruptible() on
current->parent->signal->wait_chldexit without holding any locks. It
appears that this operation should hold the tasklist_lock to dereference
current->parent and we should hold the siglock when waking up the
signal->wait_chldexit.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Some operations, like searching a directory path or connecting a unix domain
socket, make explicit calls into inode_permission. Our choices are to
either try to come up with a signature for all of the explicit calls to
inode_permission and do not check open on those, or to move the open checks to
dentry_open where we know this is always an open operation. This patch moves
the checks to dentry_open.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Previous work enabled the use of address based NetLabel selectors, which
while highly useful, brought the potential for additional per-packet overhead
when used. This patch attempts to mitigate some of that overhead by caching
the NetLabel security attribute struct within the SELinux socket security
structure. This should help eliminate the need to recreate the NetLabel
secattr structure for each packet resulting in less overhead.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Previous work enabled the use of address based NetLabel selectors, which while
highly useful, brought the potential for additional per-packet overhead when
used. This patch attempts to solve that by applying NetLabel socket labels
when sockets are connect()'d. This should alleviate the per-packet NetLabel
labeling for all connected sockets (yes, it even works for connected DGRAM
sockets).
Signed-off-by: Paul Moore <paul.moore@hp.com>
Reviewed-by: James Morris <jmorris@namei.org>
This patch builds upon the new NetLabel address selector functionality by
providing the NetLabel KAPI and CIPSO engine support needed to enable the
new packet-based labeling. The only new addition to the NetLabel KAPI at
this point is shown below:
* int netlbl_skbuff_setattr(skb, family, secattr)
... and is designed to be called from a Netfilter hook after the packet's
IP header has been populated such as in the FORWARD or LOCAL_OUT hooks.
This patch also provides the necessary SELinux hooks to support this new
functionality. Smack support is not currently included due to uncertainty
regarding the permissions needed to expand the Smack network access controls.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Reviewed-by: James Morris <jmorris@namei.org>
At some point I think I messed up and dropped the calls to netlbl_skbuff_err()
which are necessary for CIPSO to send error notifications to remote systems.
This patch re-introduces the error handling calls into the SELinux code.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
It turns out that checking to see if skb->sk is NULL is not a very good
indicator of a forwarded packet as some locally generated packets also have
skb->sk set to NULL. Fix this by not only checking the skb->sk field but also
the IP[6]CB(skb)->flags field for the IP[6]SKB_FORWARDED flag. While we are
at it, we are calling selinux_parse_skb() much earlier than we really should
resulting in potentially wasted cycles parsing packets for information we
might no use; so shuffle the code around a bit to fix this.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
We did the right thing in a few cases but there were several areas where we
determined a packet's address family based on the socket's address family which
is not the right thing to do since we can get IPv4 packets on IPv6 sockets.
This patch fixes these problems by either taking the address family directly
from the packet.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
As we are not concerned with fine-grained control over reading of
symlinks in proc, always use the default proc SID for all proc symlinks.
This should help avoid permission issues upon changes to the proc tree
as in the /proc/net -> /proc/self/net example.
This does not alter labeling of symlinks within /proc/pid directories.
ls -Zd /proc/net output before and after the patch should show the difference.
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The purpose of this patch is to assign per-thread security context
under a constraint. It enables multi-threaded server application
to kick a request handler with its fair security context, and
helps some of userspace object managers to handle user's request.
When we assign a per-thread security context, it must not have wider
permissions than the original one. Because a multi-threaded process
shares a single local memory, an arbitary per-thread security context
also means another thread can easily refer violated information.
The constraint on a per-thread security context requires a new domain
has to be equal or weaker than its original one, when it tries to assign
a per-thread security context.
Bounds relationship between two types is a way to ensure a domain can
never have wider permission than its bounds. We can define it in two
explicit or implicit ways.
The first way is using new TYPEBOUNDS statement. It enables to define
a boundary of types explicitly. The other one expand the concept of
existing named based hierarchy. If we defines a type with "." separated
name like "httpd_t.php", toolchain implicitly set its bounds on "httpd_t".
This feature requires a new policy version.
The 24th version (POLICYDB_VERSION_BOUNDARY) enables to ship them into
kernel space, and the following patch enables to handle it.
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Fix the setting of PF_SUPERPRIV by __capable() as it could corrupt the flags
the target process if that is not the current process and it is trying to
change its own flags in a different way at the same time.
__capable() is using neither atomic ops nor locking to protect t->flags. This
patch removes __capable() and introduces has_capability() that doesn't set
PF_SUPERPRIV on the process being queried.
This patch further splits security_ptrace() in two:
(1) security_ptrace_may_access(). This passes judgement on whether one
process may access another only (PTRACE_MODE_ATTACH for ptrace() and
PTRACE_MODE_READ for /proc), and takes a pointer to the child process.
current is the parent.
(2) security_ptrace_traceme(). This passes judgement on PTRACE_TRACEME only,
and takes only a pointer to the parent process. current is the child.
In Smack and commoncap, this uses has_capability() to determine whether
the parent will be permitted to use PTRACE_ATTACH if normal checks fail.
This does not set PF_SUPERPRIV.
Two of the instances of __capable() actually only act on current, and so have
been changed to calls to capable().
Of the places that were using __capable():
(1) The OOM killer calls __capable() thrice when weighing the killability of a
process. All of these now use has_capability().
(2) cap_ptrace() and smack_ptrace() were using __capable() to check to see
whether the parent was allowed to trace any process. As mentioned above,
these have been split. For PTRACE_ATTACH and /proc, capable() is now
used, and for PTRACE_TRACEME, has_capability() is used.
(3) cap_safe_nice() only ever saw current, so now uses capable().
(4) smack_setprocattr() rejected accesses to tasks other than current just
after calling __capable(), so the order of these two tests have been
switched and capable() is used instead.
(5) In smack_file_send_sigiotask(), we need to allow privileged processes to
receive SIGIO on files they're manipulating.
(6) In smack_task_wait(), we let a process wait for a privileged process,
whether or not the process doing the waiting is privileged.
I've tested this with the LTP SELinux and syscalls testscripts.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
Fix a potentially uninitialised variable in SELinux hooks that's given a
pointer to the network address by selinux_parse_skb() passing a pointer back
through its argument list. By restructuring selinux_parse_skb(), the compiler
can see that the error case need not set it as the caller will return
immediately.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch makes the needlessly global selinux_write_opts() static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
Given a hosed SELinux config in which a system never loads policy or
disables SELinux we currently just return -EINVAL for anyone trying to
read /proc/mounts. This is a configuration problem but we can certainly
be more graceful. This patch just ignores -EINVAL when displaying LSM
options and causes /proc/mounts display everything else it can. If
policy isn't loaded the obviously there are no options, so we aren't
really loosing any information here.
This is safe as the only other return of EINVAL comes from
security_sid_to_context_core() in the case of an invalid sid. Even if a
FS was mounted with a now invalidated context that sid should have been
remapped to unlabeled and so we won't hit the EINVAL and will work like
we should. (yes, I tested to make sure it worked like I thought)
Signed-off-by: Eric Paris <eparis@redhat.com>
Tested-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (39 commits)
[PATCH] fix RLIM_NOFILE handling
[PATCH] get rid of corner case in dup3() entirely
[PATCH] remove remaining namei_{32,64}.h crap
[PATCH] get rid of indirect users of namei.h
[PATCH] get rid of __user_path_lookup_open
[PATCH] f_count may wrap around
[PATCH] dup3 fix
[PATCH] don't pass nameidata to __ncp_lookup_validate()
[PATCH] don't pass nameidata to gfs2_lookupi()
[PATCH] new (local) helper: user_path_parent()
[PATCH] sanitize __user_walk_fd() et.al.
[PATCH] preparation to __user_walk_fd cleanup
[PATCH] kill nameidata passing to permission(), rename to inode_permission()
[PATCH] take noexec checks to very few callers that care
Re: [PATCH 3/6] vfs: open_exec cleanup
[patch 4/4] vfs: immutable inode checking cleanup
[patch 3/4] fat: dont call notify_change
[patch 2/4] vfs: utimes cleanup
[patch 1/4] vfs: utimes: move owner check into inode_change_ok()
[PATCH] vfs: use kstrdup() and check failing allocation
...
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
netns: fix ip_rt_frag_needed rt_is_expired
netfilter: nf_conntrack_extend: avoid unnecessary "ct->ext" dereferences
netfilter: fix double-free and use-after free
netfilter: arptables in netns for real
netfilter: ip{,6}tables_security: fix future section mismatch
selinux: use nf_register_hooks()
netfilter: ebtables: use nf_register_hooks()
Revert "pkt_sched: sch_sfq: dump a real number of flows"
qeth: use dev->ml_priv instead of dev->priv
syncookies: Make sure ECN is disabled
net: drop unused BUG_TRAP()
net: convert BUG_TRAP to generic WARN_ON
drivers/net: convert BUG_TRAP to generic WARN_ON
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds the tracehook_tracer_task() hook to consolidate all forms of
"Who is using ptrace on me?" logic. This is used for "TracerPid:" in
/proc and for permission checks. We also clean up the selinux code the
called an identical accessor.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 811f379927.
From Eric Paris:
"Please drop this patch for now. It deadlocks on ntfs-3g. I need to
rework it to handle fuse filesystems better. (casey was right)"
The register security hook is no longer required, as the capability
module is always registered. LSMs wishing to stack capability as
a secondary module should do so explicitly.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
The sb_get_mnt_opts() hook is unused, and is superseded by the
sb_show_options() hook.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: James Morris <jmorris@namei.org>
This patch causes SELinux mount options to show up in /proc/mounts. As
with other code in the area seq_put errors are ignored. Other LSM's
will not have their mount options displayed until they fill in their own
security_sb_show_options() function.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: James Morris <jmorris@namei.org>
Currently if a FS is mounted for which SELinux policy does not define an
fs_use_* that FS will either be genfs labeled or not labeled at all.
This decision is based on the existence of a genfscon rule in policy and
is irrespective of the capabilities of the filesystem itself. This
patch allows the kernel to check if the filesystem supports security
xattrs and if so will use those if there is no fs_use_* rule in policy.
An fstype with a no fs_use_* rule but with a genfs rule will use xattrs
if available and will follow the genfs rule.
This can be particularly interesting for things like ecryptfs which
actually overlays a real underlying FS. If we define excryptfs in
policy to use xattrs we will likely get this wrong at times, so with
this path we just don't need to define it!
Overlay ecryptfs on top of NFS with no xattr support:
SELinux: initialized (dev ecryptfs, type ecryptfs), uses genfs_contexts
Overlay ecryptfs on top of ext4 with xattr support:
SELinux: initialized (dev ecryptfs, type ecryptfs), uses xattr
It is also useful as the kernel adds new FS we don't need to add them in
policy if they support xattrs and that is how we want to handle them.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Use do_each_thread as a proper do/while block. Sparse complained.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Remove unused and shadowed addrlen variable. Picked up by sparse.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Paul Moore <paul.moore@hp.com>
Simplify and improve the robustness of the SELinux ioctl checking by
using the "access mode" bits of the ioctl command to determine the
permission check rather than dealing with individual command values.
This removes any knowledge of specific ioctl commands from SELinux
and follows the same guidance we gave to Smack earlier.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Enable processes with CAP_MAC_ADMIN + mac_admin permission in policy
to get undefined contexts on inodes. This extends the support for
deferred mapping of security contexts in order to permit restorecon
and similar programs to see the raw file contexts unknown to the
system policy in order to check them.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Enable security modules to distinguish reading of process state via
proc from full ptrace access by renaming ptrace_may_attach to
ptrace_may_access and adding a mode argument indicating whether only
read access or full attach access is requested. This allows security
modules to permit access to reading process state without granting
full ptrace access. The base DAC/capability checking remains unchanged.
Read access to /proc/pid/mem continues to apply a full ptrace attach
check since check_mem_permission() already requires the current task
to already be ptracing the target. The other ptrace checks within
proc for elements like environ, maps, and fds are changed to pass the
read mode instead of attach.
In the SELinux case, we model such reading of process state as a
reading of a proc file labeled with the target process' label. This
enables SELinux policy to permit such reading of process state without
permitting control or manipulation of the target process, as there are
a number of cases where programs probe for such information via proc
but do not need to be able to control the target (e.g. procps,
lsof, PolicyKit, ConsoleKit). At present we have to choose between
allowing full ptrace in policy (more permissive than required/desired)
or breaking functionality (or in some cases just silencing the denials
via dontaudit rules but this can hide genuine attacks).
This version of the patch incorporates comments from Casey Schaufler
(change/replace existing ptrace_may_attach interface, pass access
mode), and Chris Wright (provide greater consistency in the checking).
Note that like their predecessors __ptrace_may_attach and
ptrace_may_attach, the __ptrace_may_access and ptrace_may_access
interfaces use different return value conventions from each other (0
or -errno vs. 1 or 0). I retained this difference to avoid any
changes to the caller logic but made the difference clearer by
changing the latter interface to return a bool rather than an int and
by adding a comment about it to ptrace.h for any future callers.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: James Morris <jmorris@namei.org>
Formatting and syntax changes
whitespace, tabs to spaces, trailing space
put open { on same line as struct def
remove unneeded {} after if statements
change printk("Lu") to printk("llu")
convert asm/uaccess.h to linux/uaacess.h includes
remove unnecessary asm/bug.h includes
convert all users of simple_strtol to strict_strtol
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Introduce SELinux support for deferred mapping of security contexts in
the SID table upon policy reload, and use this support for inode
security contexts when the context is not yet valid under the current
policy. Only processes with CAP_MAC_ADMIN + mac_admin permission in
policy can set undefined security contexts on inodes. Inodes with
such undefined contexts are treated as having the unlabeled context
until the context becomes valid upon a policy reload that defines the
context. Context invalidation upon policy reload also uses this
support to save the context information in the SID table and later
recover it upon a subsequent policy reload that defines the context
again.
This support is to enable package managers and similar programs to set
down file contexts unknown to the system policy at the time the file
is created in order to better support placing loadable policy modules
in packages and to support build systems that need to create images of
different distro releases with different policies w/o requiring all of
the contexts to be defined or legal in the build host policy.
With this patch applied, the following sequence is possible, although
in practice it is recommended that this permission only be allowed to
specific program domains such as the package manager.
# rmdir baz
# rm bar
# touch bar
# chcon -t foo_exec_t bar # foo_exec_t is not yet defined
chcon: failed to change context of `bar' to `system_u:object_r:foo_exec_t': Invalid argument
# mkdir -Z system_u:object_r:foo_exec_t baz
mkdir: failed to set default file creation context to `system_u:object_r:foo_exec_t': Invalid argument
# cat setundefined.te
policy_module(setundefined, 1.0)
require {
type unconfined_t;
type unlabeled_t;
}
files_type(unlabeled_t)
allow unconfined_t self:capability2 mac_admin;
# make -f /usr/share/selinux/devel/Makefile setundefined.pp
# semodule -i setundefined.pp
# chcon -t foo_exec_t bar # foo_exec_t is not yet defined
# mkdir -Z system_u:object_r:foo_exec_t baz
# ls -Zd bar baz
-rw-r--r-- root root system_u:object_r:unlabeled_t bar
drwxr-xr-x root root system_u:object_r:unlabeled_t baz
# cat foo.te
policy_module(foo, 1.0)
type foo_exec_t;
files_type(foo_exec_t)
# make -f /usr/share/selinux/devel/Makefile foo.pp
# semodule -i foo.pp # defines foo_exec_t
# ls -Zd bar baz
-rw-r--r-- root root user_u:object_r:foo_exec_t bar
drwxr-xr-x root root system_u:object_r:foo_exec_t baz
# semodule -r foo
# ls -Zd bar baz
-rw-r--r-- root root system_u:object_r:unlabeled_t bar
drwxr-xr-x root root system_u:object_r:unlabeled_t baz
# semodule -i foo.pp
# ls -Zd bar baz
-rw-r--r-- root root user_u:object_r:foo_exec_t bar
drwxr-xr-x root root system_u:object_r:foo_exec_t baz
# semodule -r setundefined foo
# chcon -t foo_exec_t bar # no longer defined and not allowed
chcon: failed to change context of `bar' to `system_u:object_r:foo_exec_t': Invalid argument
# rmdir baz
# mkdir -Z system_u:object_r:foo_exec_t baz
mkdir: failed to set default file creation context to `system_u:object_r:foo_exec_t': Invalid argument
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Every implementation of ->task_kill() does nothing when the signal comes from
the kernel. This is correct, but means that check_kill_permission() should
call security_task_kill() only for SI_FROMUSER() case, and we can remove the
same check from ->task_kill() implementations.
(sadly, check_kill_permission() is the last user of signal->session/__session
but we can't s/task_session_nr/task_session/ here).
NOTE: Eric W. Biederman pointed out cap_task_kill() should die, and I think
he is very right.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: David Quigley <dpquigl@tycho.nsa.gov>
Cc: Eric Paris <eparis@redhat.com>
Cc: Harald Welte <laforge@gnumonks.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make secctx_to_secid() take constant secdata.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Don't generate the per-UID user and user session keyrings unless they're
explicitly accessed. This solves a problem during a login process whereby
set*uid() is called before the SELinux PAM module, resulting in the per-UID
keyrings having the wrong security labels.
This also cures the problem of multiple per-UID keyrings sometimes appearing
due to PAM modules (including pam_keyinit) setuiding and causing user_structs
to come into and go out of existence whilst the session keyring pins the user
keyring. This is achieved by first searching for extant per-UID keyrings
before inventing new ones.
The serial bound argument is also dropped from find_keyring_by_name() as it's
not currently made use of (setting it to 0 disables the feature).
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <kwc@citi.umich.edu>
Cc: <arunsr@cse.iitk.ac.in>
Cc: <dwalsh@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a keyctl() function to get the security label of a key.
The following is added to Documentation/keys.txt:
(*) Get the LSM security context attached to a key.
long keyctl(KEYCTL_GET_SECURITY, key_serial_t key, char *buffer,
size_t buflen)
This function returns a string that represents the LSM security context
attached to a key in the buffer provided.
Unless there's an error, it always returns the amount of data it could
produce, even if that's too big for the buffer, but it won't copy more
than requested to userspace. If the buffer pointer is NULL then no copy
will take place.
A NUL character is included at the end of the string if the buffer is
sufficiently big. This is included in the returned count. If no LSM is
in force then an empty string will be returned.
A process must have view permission on the key for this function to be
successful.
[akpm@linux-foundation.org: declare keyctl_get_security()]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add missing consts to xattr function arguments.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Filesystem capability support makes it possible to do away with (set)uid-0
based privilege and use capabilities instead. That is, with filesystem
support for capabilities but without this present patch, it is (conceptually)
possible to manage a system with capabilities alone and never need to obtain
privilege via (set)uid-0.
Of course, conceptually isn't quite the same as currently possible since few
user applications, certainly not enough to run a viable system, are currently
prepared to leverage capabilities to exercise privilege. Further, many
applications exist that may never get upgraded in this way, and the kernel
will continue to want to support their setuid-0 base privilege needs.
Where pure-capability applications evolve and replace setuid-0 binaries, it is
desirable that there be a mechanisms by which they can contain their
privilege. In addition to leveraging the per-process bounding and inheritable
sets, this should include suppressing the privilege of the uid-0 superuser
from the process' tree of children.
The feature added by this patch can be leveraged to suppress the privilege
associated with (set)uid-0. This suppression requires CAP_SETPCAP to
initiate, and only immediately affects the 'current' process (it is inherited
through fork()/exec()). This reimplementation differs significantly from the
historical support for securebits which was system-wide, unwieldy and which
has ultimately withered to a dead relic in the source of the modern kernel.
With this patch applied a process, that is capable(CAP_SETPCAP), can now drop
all legacy privilege (through uid=0) for itself and all subsequently
fork()'d/exec()'d children with:
prctl(PR_SET_SECUREBITS, 0x2f);
This patch represents a no-op unless CONFIG_SECURITY_FILE_CAPABILITIES is
enabled at configure time.
[akpm@linux-foundation.org: fix uninitialised var warning]
[serue@us.ibm.com: capabilities: use cap_task_prctl when !CONFIG_SECURITY]
Signed-off-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Reviewed-by: James Morris <jmorris@namei.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Paul Moore <paul.moore@hp.com>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
[PATCH] get rid of __exit_files(), __exit_fs() and __put_fs_struct()
[PATCH] proc_readfd_common() race fix
[PATCH] double-free of inode on alloc_file() failure exit in create_write_pipe()
[PATCH] teach seq_file to discard entries
[PATCH] umount_tree() will unhash everything itself
[PATCH] get rid of more nameidata passing in namespace.c
[PATCH] switch a bunch of LSM hooks from nameidata to path
[PATCH] lock exclusively in collect_mounts() and drop_collected_mounts()
[PATCH] move a bunch of declarations to fs/internal.h
The Fedora installer actually makes multiple NFS mounts before it loads
selinux policy. The code in selinux_clone_mnt_opts() assumed that the
init process would always be loading policy before NFS was up and
running. It might be possible to hit this in a diskless environment as
well, I'm not sure. There is no need to BUG_ON() in this situation
since we can safely continue given the circumstances.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
All whitespace and formatting. Nothing interesting to see here. About
the only thing to remember is that we aren't supposed to initialize
static variables to 0/NULL. It is done for us and doing it ourselves
puts them in a different section.
With this patch running checkpatch.pl against hooks.c only gives us
complaints about busting the 80 character limit and declaring extern's
in .c files. Apparently they don't like it, but I don't feel like going
to the trouble of moving those to .h files...
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Make sure all printk start with KERN_*
Make sure all printk end with \n
Make sure all printk have the word 'selinux' in them
Change "function name" to "%s", __func__ (found 2 wrong)
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add the security= boot parameter. This is done to avoid LSM
registration clashes in case of more than one bult-in module.
User can choose a security module to enable at boot. If no
security= boot parameter is specified, only the first LSM
asking for registration will be loaded. An invalid security
module name will be treated as if no module has been chosen.
LSM modules must check now if they are allowed to register
by calling security_module_enable(ops) first. Modify SELinux
and SMACK to do so.
Do not let SMACK register smackfs if it was not chosen on
boot. Smackfs assumes that smack hooks are registered and
the initial task security setup (swapper->security) is done.
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Setup the new Audit LSM hooks for SELinux.
Remove the now redundant exported SELinux Audit interface.
Audit: Export 'audit_krule' and 'audit_field' to the public
since their internals are needed by the implementation of the
new LSM hook 'audit_rule_known'.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Setup the new inode_getsecid and ipc_getsecid() LSM hooks
for SELinux.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Much like we added a network node cache, this patch adds a network port
cache. The design is taken almost completely from the network node cache
which in turn was taken from the network interface cache. The basic idea is
to cache entries in a hash table based on protocol/port information. The
hash function only takes the port number into account since the number of
different protocols in use at any one time is expected to be relatively
small.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Convert the strings used for mount options into #defines rather than
retyping the string throughout the SELinux code.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
