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20 commits

Author SHA1 Message Date
Vivek Goyal
43af5de742 lsm,audit,selinux: Introduce a new audit data type LSM_AUDIT_DATA_FILE
Right now LSM_AUDIT_DATA_PATH type contains "struct path" in union "u"
of common_audit_data. This information is used to print path of file
at the same time it is also used to get to dentry and inode. And this
inode information is used to get to superblock and device and print
device information.

This does not work well for layered filesystems like overlay where dentry
contained in path is overlay dentry and not the real dentry of underlying
file system. That means inode retrieved from dentry is also overlay
inode and not the real inode.

SELinux helpers like file_path_has_perm() are doing checks on inode
retrieved from file_inode(). This returns the real inode and not the
overlay inode. That means we are doing check on real inode but for audit
purposes we are printing details of overlay inode and that can be
confusing while debugging.

Hence, introduce a new type LSM_AUDIT_DATA_FILE which carries file
information and inode retrieved is real inode using file_inode(). That
way right avc denied information is given to user.

For example, following is one example avc before the patch.

  type=AVC msg=audit(1473360868.399:214): avc:  denied  { read open } for
    pid=1765 comm="cat"
    path="/root/.../overlay/container1/merged/readfile"
    dev="overlay" ino=21443
    scontext=unconfined_u:unconfined_r:test_overlay_client_t:s0:c10,c20
    tcontext=unconfined_u:object_r:test_overlay_files_ro_t:s0
    tclass=file permissive=0

It looks as follows after the patch.

  type=AVC msg=audit(1473360017.388:282): avc:  denied  { read open } for
    pid=2530 comm="cat"
    path="/root/.../overlay/container1/merged/readfile"
    dev="dm-0" ino=2377915
    scontext=unconfined_u:unconfined_r:test_overlay_client_t:s0:c10,c20
    tcontext=unconfined_u:object_r:test_overlay_files_ro_t:s0
    tclass=file permissive=0

Notice that now dev information points to "dm-0" device instead of
"overlay" device. This makes it clear that check failed on underlying
inode and not on the overlay inode.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
[PM: slight tweaks to the description to make checkpatch.pl happy]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-09-19 13:42:38 -04:00
Jeff Vander Stoep
671a2781ff security: add ioctl specific auditing to lsm_audit
Add information about ioctl calls to the LSM audit data. Log the
file path and command number.

Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Nick Kralevich <nnk@google.com>
[PM: subject line tweak]
Signed-off-by: Paul Moore <pmoore@redhat.com>
2015-07-13 13:31:58 -04:00
Eric Paris
50c205f5e5 LSM: do not initialize common_audit_data to 0
It isn't needed.  If you don't set the type of the data associated with
that type it is a pretty obvious programming bug.  So why waste the cycles?

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:04 -04:00
Eric Paris
b466066f9b LSM: remove the task field from common_audit_data
There are no legitimate users.  Always use current and get back some stack
space for the common_audit_data.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:03 -04:00
Eric Paris
bd5e50f9c1 LSM: remove the COMMON_AUDIT_DATA_INIT type expansion
Just open code it so grep on the source code works better.

Signed-off-by: Eric Paris <eparis@redhat.com>
2012-04-09 12:23:01 -04:00
Linus Torvalds
b61c37f579 lsm_audit: don't specify the audit pre/post callbacks in 'struct common_audit_data'
It just bloats the audit data structure for no good reason, since the
only time those fields are filled are just before calling the
common_lsm_audit() function, which is also the only user of those
fields.

So just make them be the arguments to common_lsm_audit(), rather than
bloating that structure that is passed around everywhere, and is
initialized in hot paths.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-03 09:49:59 -07:00
Eric Paris
48c62af68a LSM: shrink the common_audit_data data union
After shrinking the common_audit_data stack usage for private LSM data I'm
not going to shrink the data union.  To do this I'm going to move anything
larger than 2 void * ptrs to it's own structure and require it to be declared
separately on the calling stack.  Thus hot paths which don't need more than
a couple pointer don't have to declare space to hold large unneeded
structures.  I could get this down to one void * by dealing with the key
struct and the struct path.  We'll see if that is helpful after taking care of
networking.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-03 09:49:10 -07:00
Eric Paris
3b3b0e4fc1 LSM: shrink sizeof LSM specific portion of common_audit_data
Linus found that the gigantic size of the common audit data caused a big
perf hit on something as simple as running stat() in a loop.  This patch
requires LSMs to declare the LSM specific portion separately rather than
doing it in a union.  Thus each LSM can be responsible for shrinking their
portion and don't have to pay a penalty just because other LSMs have a
bigger space requirement.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-03 09:48:40 -07:00
David Howells
9ffc93f203 Remove all #inclusions of asm/system.h
Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`

Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-28 18:30:03 +01:00
Eric Paris
a269434d2f LSM: separate LSM_AUDIT_DATA_DENTRY from LSM_AUDIT_DATA_PATH
This patch separates and audit message that only contains a dentry from
one that contains a full path.  This allows us to make it harder to
misuse the interfaces or for the interfaces to be implemented wrong.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2011-04-25 18:14:07 -04:00
Eric Paris
f48b739984 LSM: split LSM_AUDIT_DATA_FS into _PATH and _INODE
The lsm common audit code has wacky contortions making sure which pieces
of information are set based on if it was given a path, dentry, or
inode.  Split this into path and inode to get rid of some of the code
complexity.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
2011-04-25 18:13:15 -04:00
John Johansen
67012e8209 AppArmor: basic auditing infrastructure.
Update lsm_audit for AppArmor specific data, and add the core routines for
AppArmor uses for auditing.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:35:11 +10:00
Eric Paris
b782e0a68d SELinux: special dontaudit for access checks
Currently there are a number of applications (nautilus being the main one) which
calls access() on files in order to determine how they should be displayed.  It
is normal and expected that nautilus will want to see if files are executable
or if they are really read/write-able.  access() should return the real
permission.  SELinux policy checks are done in access() and can result in lots
of AVC denials as policy denies RWX on files which DAC allows.  Currently
SELinux must dontaudit actual attempts to read/write/execute a file in
order to silence these messages (and not flood the logs.)  But dontaudit rules
like that can hide real attacks.  This patch addes a new common file
permission audit_access.  This permission is special in that it is meaningless
and should never show up in an allow rule.  Instead the only place this
permission has meaning is in a dontaudit rule like so:

dontaudit nautilus_t sbin_t:file audit_access

With such a rule if nautilus just checks access() we will still get denied and
thus userspace will still get the correct answer but we will not log the denial.
If nautilus attempted to actually perform one of the forbidden actions
(rather than just querying access(2) about it) we would still log a denial.
This type of dontaudit rule should be used sparingly, as it could be a
method for an attacker to probe the system permissions without detection.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by:  Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2010-08-02 15:35:07 +10:00
Eric Paris
cb84aa9b42 LSM Audit: rename LSM_AUDIT_NO_AUDIT to LSM_AUDIT_DATA_NONE
Most of the LSM common audit work uses LSM_AUDIT_DATA_* for the naming.
This was not so for LSM_AUDIT_NO_AUDIT which means the generic initializer
cannot be used.  This patch just renames the flag so the generic
initializer can be used.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-04-28 08:51:12 +10:00
Eric Paris
dd8dbf2e68 security: report the module name to security_module_request
For SELinux to do better filtering in userspace we send the name of the
module along with the AVC denial when a program is denied module_request.

Example output:

type=SYSCALL msg=audit(11/03/2009 10:59:43.510:9) : arch=x86_64 syscall=write success=yes exit=2 a0=3 a1=7fc28c0d56c0 a2=2 a3=7fffca0d7440 items=0 ppid=1727 pid=1729 auid=unset uid=root gid=root euid=root suid=root fsuid=root egid=root sgid=root fsgid=root tty=(none) ses=unset comm=rpc.nfsd exe=/usr/sbin/rpc.nfsd subj=system_u:system_r:nfsd_t:s0 key=(null)
type=AVC msg=audit(11/03/2009 10:59:43.510:9) : avc:  denied  { module_request } for  pid=1729 comm=rpc.nfsd kmod="net-pf-10" scontext=system_u:system_r:nfsd_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=system

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-11-10 09:33:46 +11:00
Thomas Liu
2bf4969032 SELinux: Convert avc_audit to use lsm_audit.h
Convert avc_audit in security/selinux/avc.c to use lsm_audit.h,
for better maintainability.

 - changed selinux to use common_audit_data instead of
    avc_audit_data
 - eliminated code in avc.c and used code from lsm_audit.h instead.

Had to add a LSM_AUDIT_NO_AUDIT to lsm_audit.h so that avc_audit
can call common_lsm_audit and do the pre and post callbacks without
doing the actual dump.  This makes it so that the patched version
behaves the same way as the unpatched version.

Also added a denied field to the selinux_audit_data private space,
once again to make it so that the patched version behaves like the
unpatched.

I've tested and confirmed that AVCs look the same before and after
this patch.

Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2009-08-17 08:37:18 +10:00
Thomas Liu
65c3f0a2d0 security: Wrap SMACK and SELINUX audit data structs in ifdefs
Wrapped the smack_audit_data and selinux_audit_data
structs in include/linux/lsm_audit.h in ifdefs so that the
union will always be the correct size.

Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-07-10 08:59:46 +10:00
Thomas Liu
d4131ded4d security: Make lsm_priv union in lsm_audit.h anonymous
Made the lsm_priv union in include/linux/lsm_audit.h
anonymous.

Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-07-10 08:58:39 +10:00
Thomas Liu
ed5215a214 Move variable function in lsm_audit.h into SMACK private space
Moved variable function in include/linux/lsm_audit.h into the
smack_audit_data struct since it is never used outside of it.

Also removed setting of function in the COMMON_AUDIT_DATA_INIT
macro because that variable is now private to SMACK.

Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
I-dont-see-any-problems-with-it: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-07-10 08:54:14 +10:00
Etienne Basset
6e837fb152 smack: implement logging V3
This patch creates auditing functions usable by LSM to audit security
events. It provides standard dumping of FS, NET, task etc ... events
(code borrowed from SELinux)
and provides 2 callbacks to define LSM specific auditing, which should be
flexible enough to convert SELinux too.

Signed-off-by: Etienne Basset <etienne.basset@numericable.fr>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
cked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-04-14 09:00:19 +10:00