Commit Graph

278 Commits

Author SHA1 Message Date
Linus Torvalds
ab074ade9c Merge git://git.infradead.org/users/eparis/audit
Pull audit updates from Eric Paris:
 "So this change across a whole bunch of arches really solves one basic
  problem.  We want to audit when seccomp is killing a process.  seccomp
  hooks in before the audit syscall entry code.  audit_syscall_entry
  took as an argument the arch of the given syscall.  Since the arch is
  part of what makes a syscall number meaningful it's an important part
  of the record, but it isn't available when seccomp shoots the
  syscall...

  For most arch's we have a better way to get the arch (syscall_get_arch)
  So the solution was two fold: Implement syscall_get_arch() everywhere
  there is audit which didn't have it.  Use syscall_get_arch() in the
  seccomp audit code.  Having syscall_get_arch() everywhere meant it was
  a useless flag on the stack and we could get rid of it for the typical
  syscall entry.

  The other changes inside the audit system aren't grand, fixed some
  records that had invalid spaces.  Better locking around the task comm
  field.  Removing some dead functions and structs.  Make some things
  static.  Really minor stuff"

* git://git.infradead.org/users/eparis/audit: (31 commits)
  audit: rename audit_log_remove_rule to disambiguate for trees
  audit: cull redundancy in audit_rule_change
  audit: WARN if audit_rule_change called illegally
  audit: put rule existence check in canonical order
  next: openrisc: Fix build
  audit: get comm using lock to avoid race in string printing
  audit: remove open_arg() function that is never used
  audit: correct AUDIT_GET_FEATURE return message type
  audit: set nlmsg_len for multicast messages.
  audit: use union for audit_field values since they are mutually exclusive
  audit: invalid op= values for rules
  audit: use atomic_t to simplify audit_serial()
  kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0]
  audit: reduce scope of audit_log_fcaps
  audit: reduce scope of audit_net_id
  audit: arm64: Remove the audit arch argument to audit_syscall_entry
  arm64: audit: Add audit hook in syscall_trace_enter/exit()
  audit: x86: drop arch from __audit_syscall_entry() interface
  sparc: implement is_32bit_task
  sparc: properly conditionalize use of TIF_32BIT
  ...
2014-10-19 16:25:56 -07:00
Richard Guy Briggs
9eab339b19 audit: get comm using lock to avoid race in string printing
When task->comm is passed directly to audit_log_untrustedstring() without
getting a copy or using the task_lock, there is a race that could happen that
would output a NULL (\0) in the output string that would effectively truncate
the rest of the report text after the comm= field in the audit, losing fields.

Use get_task_comm() to get a copy while acquiring the task_lock to prevent
this and to prevent the result from being a mixture of old and new values of
comm.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-09-23 16:37:56 -04:00
Richard Guy Briggs
9ef9151477 audit: correct AUDIT_GET_FEATURE return message type
When an AUDIT_GET_FEATURE message is sent from userspace to the kernel, it
should reply with a message tagged as an AUDIT_GET_FEATURE type with a struct
audit_feature.  The current reply is a message tagged as an AUDIT_GET
type with a struct audit_feature.

This appears to have been a cut-and-paste-eo in commit b0fed40.

Reported-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-09-23 16:37:55 -04:00
Richard Guy Briggs
54e05eddbe audit: set nlmsg_len for multicast messages.
Report:
	Looking at your example code in
	http://people.redhat.com/rbriggs/audit-multicast-listen/audit-multicast-listen.c,
	it seems that nlmsg_len field in the received messages is supposed to
	contain the length of the header + payload, but it is always set to the
	size of the header only, i.e. 16. The example program works, because
	the printf format specifies the minimum width, not "precision", so it
	simply prints out the payload until the first zero byte. This isn't too
	much of a problem, but precludes the use of recvmmsg, iiuc?

	(gdb) p *(struct nlmsghdr*)nlh
	$14 = {nlmsg_len = 16, nlmsg_type = 1100, nlmsg_flags = 0, nlmsg_seq = 0, nlmsg_pid = 9910}

The only time nlmsg_len would have been updated was at audit_buffer_alloc()
inside audit_log_start() and never updated after.  It should arguably be done
in audit_log_vformat(), but would be more efficient in audit_log_end().

Reported-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-09-23 16:37:54 -04:00
Richard Guy Briggs
01478d7d60 audit: use atomic_t to simplify audit_serial()
Since there is already a primitive to do this operation in the atomic_t, use it
to simplify audit_serial().

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-09-23 16:37:52 -04:00
Fabian Frederick
6eed9b2613 kernel/audit.c: use ARRAY_SIZE instead of sizeof/sizeof[0]
Use kernel.h definition.

Cc: Eric Paris <eparis@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-09-23 16:37:51 -04:00
Richard Guy Briggs
691e6d59d2 audit: reduce scope of audit_log_fcaps
audit_log_fcaps() isn't used outside kernel/audit.c.  Reduce its scope.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-09-23 16:37:51 -04:00
Richard Guy Briggs
c0a8d9b069 audit: reduce scope of audit_net_id
audit_net_id isn't used outside kernel/audit.c.  Reduce its scope.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-09-23 16:37:50 -04:00
Eric Paris
7d8b6c6375 CAPABILITIES: remove undefined caps from all processes
This is effectively a revert of 7b9a7ec565
plus fixing it a different way...

We found, when trying to run an application from an application which
had dropped privs that the kernel does security checks on undefined
capability bits.  This was ESPECIALLY difficult to debug as those
undefined bits are hidden from /proc/$PID/status.

Consider a root application which drops all capabilities from ALL 4
capability sets.  We assume, since the application is going to set
eff/perm/inh from an array that it will clear not only the defined caps
less than CAP_LAST_CAP, but also the higher 28ish bits which are
undefined future capabilities.

The BSET gets cleared differently.  Instead it is cleared one bit at a
time.  The problem here is that in security/commoncap.c::cap_task_prctl()
we actually check the validity of a capability being read.  So any task
which attempts to 'read all things set in bset' followed by 'unset all
things set in bset' will not even attempt to unset the undefined bits
higher than CAP_LAST_CAP.

So the 'parent' will look something like:
CapInh:	0000000000000000
CapPrm:	0000000000000000
CapEff:	0000000000000000
CapBnd:	ffffffc000000000

All of this 'should' be fine.  Given that these are undefined bits that
aren't supposed to have anything to do with permissions.  But they do...

So lets now consider a task which cleared the eff/perm/inh completely
and cleared all of the valid caps in the bset (but not the invalid caps
it couldn't read out of the kernel).  We know that this is exactly what
the libcap-ng library does and what the go capabilities library does.
They both leave you in that above situation if you try to clear all of
you capapabilities from all 4 sets.  If that root task calls execve()
the child task will pick up all caps not blocked by the bset.  The bset
however does not block bits higher than CAP_LAST_CAP.  So now the child
task has bits in eff which are not in the parent.  These are
'meaningless' undefined bits, but still bits which the parent doesn't
have.

The problem is now in cred_cap_issubset() (or any operation which does a
subset test) as the child, while a subset for valid cap bits, is not a
subset for invalid cap bits!  So now we set durring commit creds that
the child is not dumpable.  Given it is 'more priv' than its parent.  It
also means the parent cannot ptrace the child and other stupidity.

The solution here:
1) stop hiding capability bits in status
	This makes debugging easier!

2) stop giving any task undefined capability bits.  it's simple, it you
don't put those invalid bits in CAP_FULL_SET you won't get them in init
and you won't get them in any other task either.
	This fixes the cap_issubset() tests and resulting fallout (which
	made the init task in a docker container untraceable among other
	things)

3) mask out undefined bits when sys_capset() is called as it might use
~0, ~0 to denote 'all capabilities' for backward/forward compatibility.
	This lets 'capsh --caps="all=eip" -- -c /bin/bash' run.

4) mask out undefined bit when we read a file capability off of disk as
again likely all bits are set in the xattr for forward/backward
compatibility.
	This lets 'setcap all+pe /bin/bash; /bin/bash' run

Signed-off-by: Eric Paris <eparis@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Andrew G. Morgan <morgan@kernel.org>
Cc: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Steve Grubb <sgrubb@redhat.com>
Cc: Dan Walsh <dwalsh@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2014-07-24 21:53:47 +10:00
Linus Torvalds
f9da455b93 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Seccomp BPF filters can now be JIT'd, from Alexei Starovoitov.

 2) Multiqueue support in xen-netback and xen-netfront, from Andrew J
    Benniston.

 3) Allow tweaking of aggregation settings in cdc_ncm driver, from Bjørn
    Mork.

 4) BPF now has a "random" opcode, from Chema Gonzalez.

 5) Add more BPF documentation and improve test framework, from Daniel
    Borkmann.

 6) Support TCP fastopen over ipv6, from Daniel Lee.

 7) Add software TSO helper functions and use them to support software
    TSO in mvneta and mv643xx_eth drivers.  From Ezequiel Garcia.

 8) Support software TSO in fec driver too, from Nimrod Andy.

 9) Add Broadcom SYSTEMPORT driver, from Florian Fainelli.

10) Handle broadcasts more gracefully over macvlan when there are large
    numbers of interfaces configured, from Herbert Xu.

11) Allow more control over fwmark used for non-socket based responses,
    from Lorenzo Colitti.

12) Do TCP congestion window limiting based upon measurements, from Neal
    Cardwell.

13) Support busy polling in SCTP, from Neal Horman.

14) Allow RSS key to be configured via ethtool, from Venkata Duvvuru.

15) Bridge promisc mode handling improvements from Vlad Yasevich.

16) Don't use inetpeer entries to implement ID generation any more, it
    performs poorly, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits)
  rtnetlink: fix userspace API breakage for iproute2 < v3.9.0
  tcp: fixing TLP's FIN recovery
  net: fec: Add software TSO support
  net: fec: Add Scatter/gather support
  net: fec: Increase buffer descriptor entry number
  net: fec: Factorize feature setting
  net: fec: Enable IP header hardware checksum
  net: fec: Factorize the .xmit transmit function
  bridge: fix compile error when compiling without IPv6 support
  bridge: fix smatch warning / potential null pointer dereference
  via-rhine: fix full-duplex with autoneg disable
  bnx2x: Enlarge the dorq threshold for VFs
  bnx2x: Check for UNDI in uncommon branch
  bnx2x: Fix 1G-baseT link
  bnx2x: Fix link for KR with swapped polarity lane
  sctp: Fix sk_ack_backlog wrap-around problem
  net/core: Add VF link state control policy
  net/fsl: xgmac_mdio is dependent on OF_MDIO
  net/fsl: Make xgmac_mdio read error message useful
  net_sched: drr: warn when qdisc is not work conserving
  ...
2014-06-12 14:27:40 -07:00
Paul McQuade
7153e40273 ipc, kernel: use Linux headers
Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
Use #include <linux/types.h> instead of <asm/types.h>

Signed-off-by: Paul McQuade <paulmcquad@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 16:08:14 -07:00
David S. Miller
5f013c9bc7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/altera/altera_sgdma.c
	net/netlink/af_netlink.c
	net/sched/cls_api.c
	net/sched/sch_api.c

The netlink conflict dealt with moving to netlink_capable() and
netlink_ns_capable() in the 'net' tree vs. supporting 'tc' operations
in non-init namespaces.  These were simple transformations from
netlink_capable to netlink_ns_capable.

The Altera driver conflict was simply code removal overlapping some
void pointer cast cleanups in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-12 13:19:14 -04:00
Eric W. Biederman
90f62cf30a net: Use netlink_ns_capable to verify the permisions of netlink messages
It is possible by passing a netlink socket to a more privileged
executable and then to fool that executable into writing to the socket
data that happens to be valid netlink message to do something that
privileged executable did not intend to do.

To keep this from happening replace bare capable and ns_capable calls
with netlink_capable, netlink_net_calls and netlink_ns_capable calls.
Which act the same as the previous calls except they verify that the
opener of the socket had the desired permissions as well.

Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-24 13:44:54 -04:00
Richard Guy Briggs
7f74ecd788 audit: send multicast messages only if there are listeners
Test first to see if there are any userspace multicast listeners bound to the
socket before starting the multicast send work.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22 21:42:27 -04:00
Richard Guy Briggs
451f921639 audit: add netlink multicast group for log read
Add a netlink multicast socket with one group to kaudit for "best-effort"
delivery to read-only userspace clients such as systemd, in addition to the
existing bidirectional unicast auditd userspace client.

Currently, auditd is intended to use the CAP_AUDIT_CONTROL and CAP_AUDIT_WRITE
capabilities, but actually uses CAP_NET_ADMIN.  The CAP_AUDIT_READ capability
is added for use by read-only AUDIT_NLGRP_READLOG netlink multicast group
clients to the kaudit subsystem.

This will safely give access to services such as systemd to consume audit logs
while ensuring write access remains restricted for integrity.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22 21:42:27 -04:00
Richard Guy Briggs
3a101b8de0 audit: add netlink audit protocol bind to check capabilities on multicast join
Register a netlink per-protocol bind fuction for audit to check userspace
process capabilities before allowing a multicast group connection.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22 21:42:27 -04:00
Linus Torvalds
0b747172dc Merge git://git.infradead.org/users/eparis/audit
Pull audit updates from Eric Paris.

* git://git.infradead.org/users/eparis/audit: (28 commits)
  AUDIT: make audit_is_compat depend on CONFIG_AUDIT_COMPAT_GENERIC
  audit: renumber AUDIT_FEATURE_CHANGE into the 1300 range
  audit: do not cast audit_rule_data pointers pointlesly
  AUDIT: Allow login in non-init namespaces
  audit: define audit_is_compat in kernel internal header
  kernel: Use RCU_INIT_POINTER(x, NULL) in audit.c
  sched: declare pid_alive as inline
  audit: use uapi/linux/audit.h for AUDIT_ARCH declarations
  syscall_get_arch: remove useless function arguments
  audit: remove stray newline from audit_log_execve_info() audit_panic() call
  audit: remove stray newlines from audit_log_lost messages
  audit: include subject in login records
  audit: remove superfluous new- prefix in AUDIT_LOGIN messages
  audit: allow user processes to log from another PID namespace
  audit: anchor all pid references in the initial pid namespace
  audit: convert PPIDs to the inital PID namespace.
  pid: get pid_t ppid of task in init_pid_ns
  audit: rename the misleading audit_get_context() to audit_take_context()
  audit: Add generic compat syscall support
  audit: Add CONFIG_HAVE_ARCH_AUDITSYSCALL
  ...
2014-04-12 12:38:53 -07:00
Eric Paris
543bc6a1a9 AUDIT: Allow login in non-init namespaces
It its possible to configure your PAM stack to refuse login if audit
messages (about the login) were unable to be sent.  This is common in
many distros and thus normal configuration of many containers.  The PAM
modules determine if audit is enabled/disabled in the kernel based on
the return value from sending an audit message on the netlink socket.
If userspace gets back ECONNREFUSED it believes audit is disabled in the
kernel.  If it gets any other error else it refuses to let the login
proceed.

Just about ever since the introduction of namespaces the kernel audit
subsystem has returned EPERM if the task sending a message was not in
the init user or pid namespace.  So many forms of containers have never
worked if audit was enabled in the kernel.

BUT if the container was not in net_init then the kernel network code
would send ECONNREFUSED (instead of the audit code sending EPERM).  Thus
by pure accident/dumb luck/bug if an admin configured the PAM stack to
reject all logins that didn't talk to audit, but then ran the login
untility in the non-init_net namespace, it would work!! Clearly this was
a bug, but it is a bug some people expected.

With the introduction of network namespace support in 3.14-rc1 the two
bugs stopped cancelling each other out.  Now, containers in the
non-init_net namespace refused to let users log in (just like PAM was
configfured!) Obviously some people were not happy that what used to let
users log in, now didn't!

This fix is kinda hacky.  We return ECONNREFUSED for all non-init
relevant namespaces.  That means that not only will the old broken
non-init_net setups continue to work, now the broken non-init_pid or
non-init_user setups will 'work'.  They don't really work, since audit
isn't logging things.  But it's what most users want.

In 3.15 we should have patches to support not only the non-init_net
(3.14) namespace but also the non-init_pid and non-init_user namespace.
So all will be right in the world.  This just opens the doors wide open
on 3.14 and hopefully makes users happy, if not the audit system...

Reported-by: Andre Tomt <andre@tomt.net>
Reported-by: Adam Richter <adam_richter2004@yahoo.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Conflicts:
	kernel/audit.c
2014-03-31 15:36:41 -04:00
Eric Paris
aa4af831bb AUDIT: Allow login in non-init namespaces
It its possible to configure your PAM stack to refuse login if audit
messages (about the login) were unable to be sent.  This is common in
many distros and thus normal configuration of many containers.  The PAM
modules determine if audit is enabled/disabled in the kernel based on
the return value from sending an audit message on the netlink socket.
If userspace gets back ECONNREFUSED it believes audit is disabled in the
kernel.  If it gets any other error else it refuses to let the login
proceed.

Just about ever since the introduction of namespaces the kernel audit
subsystem has returned EPERM if the task sending a message was not in
the init user or pid namespace.  So many forms of containers have never
worked if audit was enabled in the kernel.

BUT if the container was not in net_init then the kernel network code
would send ECONNREFUSED (instead of the audit code sending EPERM).  Thus
by pure accident/dumb luck/bug if an admin configured the PAM stack to
reject all logins that didn't talk to audit, but then ran the login
untility in the non-init_net namespace, it would work!! Clearly this was
a bug, but it is a bug some people expected.

With the introduction of network namespace support in 3.14-rc1 the two
bugs stopped cancelling each other out.  Now, containers in the
non-init_net namespace refused to let users log in (just like PAM was
configfured!) Obviously some people were not happy that what used to let
users log in, now didn't!

This fix is kinda hacky.  We return ECONNREFUSED for all non-init
relevant namespaces.  That means that not only will the old broken
non-init_net setups continue to work, now the broken non-init_pid or
non-init_user setups will 'work'.  They don't really work, since audit
isn't logging things.  But it's what most users want.

In 3.15 we should have patches to support not only the non-init_net
(3.14) namespace but also the non-init_pid and non-init_user namespace.
So all will be right in the world.  This just opens the doors wide open
on 3.14 and hopefully makes users happy, if not the audit system...

Reported-by: Andre Tomt <andre@tomt.net>
Reported-by: Adam Richter <adam_richter2004@yahoo.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-30 17:02:53 -07:00
Monam Agarwal
e231d54c12 kernel: Use RCU_INIT_POINTER(x, NULL) in audit.c
This patch replaces rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL)

The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structure.
And in the case of the NULL pointer, there is no structure to initialize.
So, rcu_assign_pointer(p, NULL) can be safely converted to RCU_INIT_POINTER(p, NULL)

Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-03-24 12:00:22 -04:00
Josh Boyer
f12835276c audit: remove stray newlines from audit_log_lost messages
Calling audit_log_lost with a \n in the format string leads to extra
newlines in dmesg.  That function will eventually call audit_panic which
uses pr_err with an explicit \n included.  Just make these calls match the
others that lack \n.

Reported-by: Jonathan Kamens <jik@kamens.brookline.ma.us>
Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:58 -04:00
Richard Guy Briggs
5a3cb3b6c3 audit: allow user processes to log from another PID namespace
Still only permit the audit logging daemon and control to operate from the
initial PID namespace, but allow processes to log from another PID namespace.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
(informed by ebiederman's c776b5d2)

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:56 -04:00
Richard Guy Briggs
f1dc4867ff audit: anchor all pid references in the initial pid namespace
Store and log all PIDs with reference to the initial PID namespace and
use the access functions task_pid_nr() and task_tgid_nr() for task->pid
and task->tgid.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
(informed by ebiederman's c776b5d2)
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:55 -04:00
Richard Guy Briggs
c92cdeb45e audit: convert PPIDs to the inital PID namespace.
sys_getppid() returns the parent pid of the current process in its own pid
namespace.  Since audit filters are based in the init pid namespace, a process
could avoid a filter or trigger an unintended one by being in an alternate pid
namespace or log meaningless information.

Switch to task_ppid_nr() for PPIDs to anchor all audit filters in the
init_pid_ns.

(informed by ebiederman's 6c621b7e)
Cc: stable@vger.kernel.org
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:55 -04:00
Eric W. Biederman
099dd23511 audit: Send replies in the proper network namespace.
In perverse cases of file descriptor passing the current network
namespace of a process and the network namespace of a socket used by
that socket may differ.  Therefore use the network namespace of the
appropiate socket to ensure replies always go to the appropiate
socket.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-03-20 10:11:02 -04:00
Eric W. Biederman
638a0fd2a0 audit: Use struct net not pid_t to remember the network namespce to reply in
While reading through 3.14-rc1 I found a pretty siginficant mishandling
of network namespaces in the recent audit changes.

In struct audit_netlink_list and audit_reply add a reference to the
network namespace of the caller and remove the userspace pid of the
caller.  This cleanly remembers the callers network namespace, and
removes a huge class of races and nasty failure modes that can occur
when attempting to relook up the callers network namespace from a pid_t
(including the caller's network namespace changing, pid wraparound, and
the pid simply not being present).

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-03-20 10:10:53 -04:00
Eric W. Biederman
d211f177b2 audit: Update kdoc for audit_send_reply and audit_list_rules_send
The kbuild test robot reported:
> tree:   git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git for-next
> head:   6f285b19d0
> commit: 6f285b19d0 [2/2] audit: Send replies in the proper network namespace.
> reproduce: make htmldocs
>
> >> Warning(kernel/audit.c:575): No description found for parameter 'request_skb'
> >> Warning(kernel/audit.c:575): Excess function parameter 'portid' description in 'audit_send_reply'
> >> Warning(kernel/auditfilter.c:1074): No description found for parameter 'request_skb'
> >> Warning(kernel/auditfilter.c:1074): Excess function parameter 'portid' description in 'audit_list_rules_s

Which was caused by my failure to update the kdoc annotations when I
updated the functions.  Fix that small oversight now.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2014-03-08 15:31:54 -08:00
Eric W. Biederman
6f285b19d0 audit: Send replies in the proper network namespace.
In perverse cases of file descriptor passing the current network
namespace of a process and the network namespace of a socket used by
that socket may differ.  Therefore use the network namespace of the
appropiate socket to ensure replies always go to the appropiate
socket.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2014-02-28 19:44:55 -08:00
Eric W. Biederman
48095d991d audit: Use struct net not pid_t to remember the network namespce to reply in
In struct audit_netlink_list and audit_reply add a reference to the
network namespace of the caller and remove the userspace pid of the
caller.  This cleanly remembers the callers network namespace, and
removes a huge class of races and nasty failure modes that can occur
when attempting to relook up the callers network namespace from a
pid_t (including the caller's network namespace changing, pid
wraparound, and the pid simply not being present).

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2014-02-28 04:04:33 -08:00
Richard Guy Briggs
8626877b52 audit: fix location of __net_initdata for audit_net_ops
Fixup caught by checkpatch.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-17 17:14:32 -05:00
Eric Paris
4f066328ab audit: remove pr_info for every network namespace
A message about creating the audit socket might be fine at startup, but
a pr_info for every single network namespace created on a system isn't
useful.

Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-17 17:04:38 -05:00
Joe Perches
3e1d0bb622 audit: Convert int limit uses to u32
The equivalent uapi struct uses __u32 so make the kernel
uses u32 too.

This can prevent some oddities where the limit is
logged/emitted as a negative value.

Convert kstrtol to kstrtouint to disallow negative values.

Signed-off-by: Joe Perches <joe@perches.com>
[eparis: do not remove static from audit_default declaration]
2014-01-14 14:54:00 -05:00
Joe Perches
d957f7b726 audit: Use more current logging style
Add pr_fmt to prefix "audit: " to output
Convert printk(KERN_<LEVEL> to pr_<level>
Coalesce formats
Use pr_cont
Move a brace after switch

Signed-off-by: Joe Perches <joe@perches.com>
2014-01-14 14:53:54 -05:00
Joe Perches
b8dbc3241f audit: Use hex_byte_pack_upper
Using the generic kernel function causes the
object size to increase with gcc 4.8.1.

$ size kernel/audit.o*
   text	   data	    bss	    dec	    hex	filename
  18577	   6079	   8436	  33092	   8144	kernel/audit.o.new
  18579	   6015	   8420	  33014	   80f6	kernel/audit.o.old

Unsigned...
2014-01-14 14:53:50 -05:00
Eric Paris
1ce319f11c audit: reorder AUDIT_TTY_SET arguments
An admin is likely to want to see old and new values next to each other.
Putting all of the old values followed by all of the new values is just
hard to read as a human.

Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:33:41 -05:00
Eric Paris
0e23baccaa audit: rework AUDIT_TTY_SET to only grab spin_lock once
We can simplify the AUDIT_TTY_SET code to only grab the spin_lock one
time.  We need to determine if the new values are valid and if so, set
the new values at the same time we grab the old onces.  While we are
here get rid of 'res' and just use err.

Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:33:41 -05:00
Eric Paris
3f0c5fad89 audit: remove needless switch in AUDIT_SET
If userspace specified that it was setting values via the mask we do not
need a second check to see if they also set the version field high
enough to understand those values.  (clearly if they set the mask they
knew those values).

Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:33:39 -05:00
Eric Paris
70249a9cfd audit: use define's for audit version
Give names to the audit versions.  Just something for a userspace
programmer to know what the version provides.

Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:33:36 -05:00
Eric Paris
c81825dd6b audit: wait_for_auditd rework for readability
We had some craziness with signed to unsigned long casting which appears
wholely unnecessary.  Just use signed long.  Even though 2 values of the
math equation are unsigned longs the result is expected to be a signed
long.  So why keep casting the result to signed long?  Just make it
signed long and use it.

We also remove the needless "timeout" variable.  We already have the
stack "sleep_time" variable.  Just use that...

Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:33:27 -05:00
Richard Guy Briggs
ad2ac26327 audit: log task info on feature change
Add task information to the log when changing a feature state.

Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:32:56 -05:00
Gao feng
de92fc97e1 audit: fix incorrect set of audit_sock
NETLINK_CB(skb).sk is the socket of user space process,
netlink_unicast in kauditd_send_skb wants the kernel
side socket. Since the sk_state of audit netlink socket
is not NETLINK_CONNECTED, so the netlink_getsockbyportid
doesn't return -ECONNREFUSED.

And the socket of userspace process can be released anytime,
so the audit_sock may point to invalid socket.

this patch sets the audit_sock to the kernel side audit
netlink socket.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:32:49 -05:00
Gao feng
11ee39ebf7 audit: print error message when fail to create audit socket
print the error message and then return -ENOMEM.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:32:44 -05:00
Richard Guy Briggs
724e4fcc8d audit: log on errors from filter user rules
An error on an AUDIT_NEVER rule disabled logging on that rule.
On error on AUDIT_NEVER rules, log.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:32:31 -05:00
Toshiyuki Okajima
6dd80aba90 audit: audit_log_start running on auditd should not stop
The backlog cannot be consumed when audit_log_start is running on auditd
even if audit_log_start calls wait_for_auditd to consume it.
The situation is the deadlock because only auditd can consume the backlog.
If the other process needs to send the backlog, it can be also stopped
by the deadlock.

So, audit_log_start running on auditd should not stop.

You can see the deadlock with the following reproducer:
 # auditctl -a exit,always -S all
 # reboot

Signed-off-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Reviewed-by: gaofeng@cn.fujitsu.com
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:32:22 -05:00
Richard Guy Briggs
1b7b533f65 audit: drop audit_cmd_lock in AUDIT_USER family of cases
We do not need to hold the audit_cmd_mutex for this family of cases.  The
possible exception to this is the call to audit_filter_user(), so drop the lock
immediately after.  To help in fixing the race we are trying to avoid, make
sure that nothing called by audit_filter_user() calls audit_log_start().  In
particular, watch out for *_audit_rule_match().

This fix will take care of systemd and anything USING audit.  It still means
that we could race with something configuring audit and auditd shutting down.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Reported-by: toshi.okajima@jp.fujitsu.com
Tested-by: toshi.okajima@jp.fujitsu.com
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:32:11 -05:00
Eric Paris
4440e85481 audit: convert all sessionid declaration to unsigned int
Right now the sessionid value in the kernel is a combination of u32,
int, and unsigned int.  Just use unsigned int throughout.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:31:46 -05:00
Paul Davies C
ff235f51a1 audit: Added exe field to audit core dump signal log
Currently when the coredump signals are logged by the audit system, the
actual path to the executable is not logged. Without details of exe, the
system admin may not have an exact idea on what program failed.

This patch changes the audit_log_task() so that the path to the exe is also
logged.

This was copied from audit_log_task_info() and the latter enhanced to avoid
disappearing text fields.

Signed-off-by: Paul Davies C <pauldaviesc@gmail.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:31:38 -05:00
Richard Guy Briggs
34eab0a7cd audit: prevent an older auditd shutdown from orphaning a newer auditd startup
There have been reports of auditd restarts resulting in kaudit not being able
to find a newly registered auditd.  It results in reports such as:
	kernel: [ 2077.233573] audit: *NO* daemon at audit_pid=1614
	kernel: [ 2077.234712] audit: audit_lost=97 audit_rate_limit=0 audit_backlog_limit=320
	kernel: [ 2077.234718] audit: auditd disappeared
		(previously mis-spelled "dissapeared")

One possible cause is a race between the shutdown of an older auditd and a
newer one.  If the newer one sets the daemon pid to itself in kauditd before
the older one has cleared the daemon pid, the newer daemon pid will be erased.
This could be caused by an automated system, or by manual intervention, but in
either case, there is no use in having the older daemon clear the daemon pid
reference since its old pid is no longer being referenced.  This patch will
prevent that specific case, returning an error of EACCES.

The case for preventing a newer auditd from registering itself if there is an
existing auditd is a more difficult case that is beyond the scope of this
patch.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:31:27 -05:00
Richard Guy Briggs
ce0d9f0469 audit: refactor audit_receive_msg() to clarify AUDIT_*_RULE* cases
audit_receive_msg() needlessly contained a fallthrough case that called
audit_receive_filter(), containing no common code between the cases.  Separate
them to make the logic clearer.  Refactor AUDIT_LIST_RULES, AUDIT_ADD_RULE,
AUDIT_DEL_RULE cases to create audit_rule_change(), audit_list_rules_send()
functions.  This should not functionally change the logic.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:31:22 -05:00
Richard Guy Briggs
a06e56b2a1 audit: log AUDIT_TTY_SET config changes
Log transition of config changes when AUDIT_TTY_SET is called, including both
enabled and log_passwd values now in the struct.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-01-13 22:31:15 -05:00