1
linux/kernel
Pavel Emelyanov 75c0371a2d audit: netlink socket can be auto-bound to pid other than current->pid (v2)
From:	Pavel Emelyanov <xemul@openvz.org>

This patch is based on the one from Thomas.

The kauditd_thread() calls the netlink_unicast() and passes 
the audit_pid to it. The audit_pid, in turn, is received from 
the user space and the tool (I've checked the audit v1.6.9) 
uses getpid() to pass one in the kernel. Besides, this tool 
doesn't bind the netlink socket to this id, but simply creates 
it allowing the kernel to auto-bind one.

That's the preamble.

The problem is that netlink_autobind() _does_not_ guarantees
that the socket will be auto-bound to the current pid. Instead
it uses the current pid as a hint to start looking for a free
id. So, in case of conflict, the audit messages can be sent
to a wrong socket. This can happen (it's unlikely, but can be)
in case some task opens more than one netlink sockets and then
the audit one starts - in this case the audit's pid can be busy
and its socket will be bound to another id.

The proposal is to introduce an audit_nlk_pid in audit subsys,
that will point to the netlink socket to send packets to. It
will most often be equal to audit_pid. The socket id can be 
got from the skb's netlink CB right in the audit_receive_msg.
The audit_nlk_pid reset to 0 is not required, since all the
decisions are taken based on audit_pid value only.

Later, if the audit tools will bind the socket themselves, the
kernel will have to provide a way to setup the audit_nlk_pid
as well.

A good side effect of this patch is that audit_pid can later 
be converted to struct pid, as it is not longer safe to use 
pid_t-s in the presence of pid namespaces. But audit code still 
uses the tgid from task_struct in the audit_signal_info and in
the audit_filter_syscall.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-20 15:39:41 -07:00
..
irq genirq: do not leave interupts enabled on free_irq 2008-02-19 10:43:58 +01:00
power Merge branches 'release' and 'doc' into release 2008-03-13 01:59:53 -04:00
time time: remove obsolete CLOCK_TICK_ADJUST 2008-03-09 08:42:57 +01:00
.gitignore Update kernel/.gitignore with new auto-generated files 2008-02-09 23:27:01 -08:00
acct.c acct: real_parent ppid 2008-01-07 14:55:37 -08:00
audit_tree.c Introduce path_put() 2008-02-14 21:13:33 -08:00
audit.c audit: netlink socket can be auto-bound to pid other than current->pid (v2) 2008-03-20 15:39:41 -07:00
audit.h [PATCH] audit: watching subtrees 2007-10-21 02:37:45 -04:00
auditfilter.c Introduce path_put() 2008-02-14 21:13:33 -08:00
auditsc.c [PATCH] Audit: Fix the format type for size_t variables 2008-03-01 07:16:06 -05:00
backtracetest.c x86: add a simple backtrace test module 2008-01-30 13:33:08 +01:00
capability.c Add 64-bit capability support to the kernel 2008-02-05 09:44:20 -08:00
cgroup_debug.c Task Control Groups: simple task cgroup debug info subsystem 2007-10-19 11:53:36 -07:00
cgroup.c cgroup: fix default notify_on_release setting 2008-03-04 16:35:09 -08:00
compat.c hrtimer: don't modify restart_block->fn in restart functions 2008-02-10 10:48:03 +01:00
configs.c
cpu.c cpu: fix section mismatch warnings for enable_nonboot_cpus 2008-02-08 09:22:41 -08:00
cpuset.c cpusets: fix obsolete comment 2008-03-05 17:53:33 -08:00
delayacct.c Add scaled time to taskstats based process accounting 2007-10-18 14:37:28 -07:00
dma.c whitespace fixes: DMA channel allocator 2007-10-18 14:37:24 -07:00
exec_domain.c whitespace fixes: execution domains 2007-10-18 14:37:26 -07:00
exit.c Fix waitid si_code regression 2008-03-08 11:54:00 -08:00
extable.c module: Don't report discarded init pages as kernel text. 2008-01-29 17:13:18 +11:00
fork.c Use struct path in fs_struct 2008-02-14 21:13:33 -08:00
futex_compat.c futex: runtime enable pi and robust functionality 2008-02-23 17:12:15 -08:00
futex.c futex: runtime enable pi and robust functionality 2008-02-23 17:12:15 -08:00
hrtimer.c hrtimer: catch expired CLOCK_REALTIME timers early 2008-02-14 22:08:30 +01:00
itimer.c ITIMER_REAL: convert to use struct pid 2008-02-08 09:22:29 -08:00
kallsyms.c remove support for un-needed _extratext section 2008-02-06 10:41:01 -08:00
Kconfig.hz sched: high-res preemption tick 2008-01-25 21:08:29 +01:00
Kconfig.preempt rcu: move PREEMPT_RCU config option back under PREEMPT 2008-03-10 18:01:20 -07:00
kexec.c vmcoreinfo: add "VMCOREINFO_" to all the call for vmcoreinfo_append_str() 2008-02-07 08:42:25 -08:00
kfifo.c
kmod.c Dont touch fs_struct in usermodehelper 2008-02-14 21:13:32 -08:00
kprobes.c kprobes: fix a null pointer bug in register_kretprobe() 2008-03-04 16:35:19 -08:00
ksysfs.c Kobject: convert remaining kobject_unregister() to kobject_put() 2008-01-24 20:40:40 -08:00
kthread.c sched: fix, always create kernel threads with normal priority 2008-01-25 21:08:33 +01:00
latencytop.c sched: latencytop support 2008-01-25 21:08:34 +01:00
lockdep_internals.h
lockdep_proc.c
lockdep.c Subject: lockdep: include all lock classes in all_lock_classes 2008-02-25 23:03:02 +01:00
Makefile avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
marker.c markers: don't risk NULL deref in marker 2008-03-04 16:35:14 -08:00
module.c modules: warn about suspicious return values from module's ->init() hook 2008-03-10 18:01:20 -07:00
mutex-debug.c kernel: remove fastcall in kernel/* 2008-02-08 09:22:31 -08:00
mutex-debug.h
mutex.c kernel: remove fastcall in kernel/* 2008-02-08 09:22:31 -08:00
mutex.h
notifier.c kernel/notifier.c should #include <linux/reboot.h> 2008-02-06 10:41:02 -08:00
ns_cgroup.c cgroups: implement namespace tracking subsystem 2007-10-19 11:53:37 -07:00
nsproxy.c namespaces: move the IPC namespace under IPC_NS option 2008-02-08 09:22:23 -08:00
panic.c ACPI: Taint kernel on ACPI table override (format corrected) 2008-02-06 22:07:51 -05:00
params.c Add new string functions strict_strto* and convert kernel params to use them 2008-02-08 09:22:41 -08:00
pid_namespace.c namespaces: cleanup the code managed with PID_NS option 2008-02-08 09:22:23 -08:00
pid.c kernel: remove fastcall in kernel/* 2008-02-08 09:22:31 -08:00
pm_qos_params.c pm qos infrastructure and interface 2008-02-05 09:44:22 -08:00
posix-cpu-timers.c Use find_task_by_vpid in posix timers 2008-02-08 09:22:41 -08:00
posix-timers.c hrtimer: check relative timeouts for overflow 2008-02-14 22:08:30 +01:00
printk.c printk: fix possible printk overrun 2008-02-26 07:42:37 -08:00
profile.c Nuke a duplicate include from profile.c 2008-02-08 09:22:34 -08:00
ptrace.c ptrace_check_attach: remove unneeded ->signal != NULL check 2008-02-08 09:22:26 -08:00
rcuclassic.c Preempt-RCU: implementation 2008-01-25 21:08:24 +01:00
rcupdate.c rcupdate: fix comment 2008-02-13 16:21:18 -08:00
rcupreempt_trace.c Preempt-RCU: implementation 2008-01-25 21:08:24 +01:00
rcupreempt.c rcupreempt: remove never-migrates assumption from rcu_process_callbacks() 2008-02-29 20:21:13 +01:00
rcutorture.c cpu-hotplug: replace lock_cpu_hotplug() with get_online_cpus() 2008-01-25 21:08:02 +01:00
relay.c relay: nopage 2008-02-06 10:41:07 -08:00
res_counter.c Memory Resource Controller use strstrip while parsing arguments 2008-03-04 16:35:09 -08:00
resource.c [POWERPC] Add arch-specific walk_memory_remove() for 64-bit powerpc 2008-02-08 19:52:48 +11:00
rtmutex_common.h Don't operate with pid_t in rtmutex tester 2008-02-08 09:22:41 -08:00
rtmutex-debug.c Don't operate with pid_t in rtmutex tester 2008-02-08 09:22:41 -08:00
rtmutex-debug.h
rtmutex-tester.c Driver core: change sysdev classes to use dynamic kobject names 2008-01-24 20:40:40 -08:00
rtmutex.c hrtimer: more hrtimer_init_sleeper() fallout. 2008-02-13 15:45:36 +01:00
rtmutex.h
rwsem.c sched: mark rwsem functions as __sched for wchan/profiling 2007-12-18 15:21:13 +01:00
sched_debug.c sched: keep total / count stats in addition to the max for 2008-01-25 21:08:35 +01:00
sched_fair.c sched: simplify sched_slice() 2008-03-15 03:02:50 +01:00
sched_idletask.c sched: high-res preemption tick 2008-01-25 21:08:29 +01:00
sched_rt.c sched: balance RT task resched only on runqueue 2008-03-07 16:43:00 +01:00
sched_stats.h sched: clean up kernel/sched_stat.h 2007-11-28 15:52:56 +01:00
sched.c sched: fix overload performance: buddy wakeups 2008-03-15 03:02:50 +01:00
seccomp.c
signal.c freezer vs stopped or traced 2008-03-04 07:59:54 -08:00
softirq.c rcu: add support for dynamic ticks and preempt rcu 2008-02-29 18:46:50 +01:00
softlockup.c softlockup: fix task state setting 2008-02-29 18:46:53 +01:00
spinlock.c spinlock: lockbreak cleanup 2008-01-30 13:31:20 +01:00
srcu.c make srcu_readers_active() static 2008-02-06 10:41:02 -08:00
stacktrace.c
stop_machine.c stopmachine: semaphore to mutex 2008-02-06 10:41:08 -08:00
sys_ni.c timerfd: new timerfd API 2008-02-05 09:44:07 -08:00
sys.c Pidns: make full use of xxx_vnr() calls 2008-02-08 09:22:29 -08:00
sysctl_check.c constify tables in kernel/sysctl_check.c 2008-02-08 09:22:31 -08:00
sysctl.c sched: revert load_balance_monitor() changes 2008-03-04 17:54:06 +01:00
taskstats.c kernel/taskstats.c: fix bogus nlmsg_free() 2007-11-14 18:45:44 -08:00
test_kprobes.c kprobes: kretprobe user entry-handler 2008-02-06 10:41:11 -08:00
time.c avoid overflows in kernel/time.c 2008-02-08 09:22:39 -08:00
timeconst.pl timeconst.pl: correct reversal of USEC_TO_HZ and HZ_TO_USEC 2008-02-12 14:29:26 -08:00
timer.c kernel: remove fastcall in kernel/* 2008-02-08 09:22:31 -08:00
tsacct.c Add scaled time to taskstats based process accounting 2007-10-18 14:37:28 -07:00
uid16.c
user_namespace.c namespaces: cleanup the code managed with the USER_NS option 2008-02-08 09:22:23 -08:00
user.c sched: rt-group: make rt groups scheduling configurable 2008-02-13 15:45:40 +01:00
utsname_sysctl.c Isolate the UTS namespace's domainname and hostname back 2007-11-29 09:24:53 -08:00
utsname.c
wait.c kernel: remove fastcall in kernel/* 2008-02-08 09:22:31 -08:00
workqueue.c workqueue: make delayed_work_timer_fn() static 2008-02-08 09:22:37 -08:00