[PATCH 06/11] Task watchers: Register audit task watcher

Matt Helsley
2006-06-14T00:01:59Z

Adapt audit to use task watchers.

Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-audit@redhat.com
--

kernel/audit.c | 25 ++++++++++++++++++++++++-
kernel/exit.c | 3 ---
kernel/fork.c | 7 +------
3 files changed, 25 insertions(+), 10 deletions(-)

Index: linux-2.6.17-rc5-mm2/kernel/exit.c
===================================================================
--- linux-2.6.17-rc5-mm2.orig/kernel/exit.c
+++ linux-2.6.17-rc5-mm2/kernel/exit.c
@@ -35,11 +35,10 @@
#include <linux/posix-timers.h>
#include <linux/mutex.h>
#include <linux/futex.h>
#include <linux/compat.h>
#include <linux/pipe_fs_i.h>
-#include <linux/audit.h> /* for audit_free() */
#include <linux/resource.h>
#include <linux/notifier.h>

#include <asm/uaccess.h>
#include <asm/unistd.h>
@@ -914,12 +913,10 @@ fastcall NORET_TYPE void do_exit(long co
exit_robust_list(tsk);
#ifdef CONFIG_COMPAT
if (unlikely(tsk->compat_robust_list))
compat_exit_robust_list(tsk);
#endif
- if (unlikely(tsk->audit_context))
- audit_free(tsk);
tsk->exit_code = code;
taskstats_exit_send(tsk, tidstats, tgidstats);
taskstats_exit_free(tidstats, tgidstats);
delayacct_tsk_exit(tsk);
notify_result = notify_watchers(WATCH_TASK_FREE, tsk);
Index: linux-2.6.17-rc5-mm2/kernel/audit.c
===================================================================
--- linux-2.6.17-rc5-mm2.orig/kernel/audit.c
+++ linux-2.6.17-rc5-mm2/kernel/audit.c
@@ -46,10 +46,11 @@
#include <asm/atomic.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/kthread.h>
+#include <linux/notifier.h>

#include <linux/audit.h>

#include <net/sock.h>
#include <net/netlink.h>
@@ -64,10 +65,30 @@
static int audit_initialized;

/* No syscall auditing will take place unless audit_enabled != 0. */
int audit_enabled;

+static int audit_task(struct notifier_block *nb, unsigned long val, void *t)
+{
+ struct task_struct *tsk = t;
+
+ switch(get_watch_event(val)) {
+ case WATCH_TASK_INIT:
+ /* Hack: -EFOO sets NOTIFY_STOP_MASK */
+ return audit_alloc(tsk);
+ case WATCH_TASK_FREE:
+ if (unlikely(tsk->audit_context))
+ audit_free(tsk);
+ default:
+ return NOTIFY_DONE;
+ }
+}
+
+static struct notifier_block __read_mostly audit_watch_tasks_nb = {
+ .notifier_call = audit_task,
+};
+
/* Default state when kernel boots without any parameters. */
static int audit_default;

/* If auditing cannot proceed, audit_failure selects what happens. */
static int audit_failure = AUDIT_FAIL_PRINTK;
@@ -707,12 +728,14 @@ static int __init audit_enable(char *str
{
audit_default = !!simple_strtol(str, NULL, 0);
printk(KERN_INFO "audit: %s%s\n",
audit_default ? "enabled" : "disabled",
audit_initialized ? "" : " (after initialization)");
- if (audit_initialized)
+ if (audit_initialized) {
audit_enabled = audit_default;
+ register_task_watcher(&audit_watch_tasks_nb);
+ }
return 1;
}

__setup("audit=", audit_enable);

Index: linux-2.6.17-rc5-mm2/kernel/fork.c
===================================================================
--- linux-2.6.17-rc5-mm2.orig/kernel/fork.c
+++ linux-2.6.17-rc5-mm2/kernel/fork.c
@@ -38,11 +38,10 @@
#include <linux/jiffies.h>
#include <linux/futex.h>
#include <linux/rcupdate.h>
#include <linux/ptrace.h>
#include <linux/mount.h>
-#include <linux/audit.h>
#include <linux/profile.h>
#include <linux/rmap.h>
#include <linux/acct.h>
#include <linux/delayacct.h>
#include <linux/notifier.h>
@@ -1088,15 +1087,13 @@ static task_t *copy_process(unsigned lon
p->softirq_context = 0;
#endif

if ((retval = security_task_alloc(p)))
goto bad_fork_cleanup_policy;
- if ((retval = audit_alloc(p)))
- goto bad_fork_cleanup_security;
/* copy all the process information */
if ((retval = copy_semundo(clone_flags, p)))
- goto bad_fork_cleanup_audit;
+ goto bad_fork_cleanup_security;
if ((retval = copy_files(clone_flags, p)))
goto bad_fork_cleanup_semundo;
if ((retval = copy_fs(clone_flags, p)))
goto bad_fork_cleanup_files;
if ((retval = copy_sighand(clone_flags, p)))
@@ -1270,12 +1267,10 @@ bad_fork_cleanup_fs:
exit_fs(p); /* blocking */
bad_fork_cleanup_files:
exit_files(p); /* blocking */
bad_fork_cleanup_semundo:
exit_sem(p);
-bad_fork_cleanup_audit:
- audit_free(p);
bad_fork_cleanup_security:
security_task_free(p);
notify_result = notify_watchers(WATCH_TASK_FREE, p);
WARN_ON(notify_result & NOTIFY_STOP_MASK);
bad_fork_cleanup_policy:

--