[PATCH ghak81 RFC V2 5/5] audit: collect audit task parameters

From: Richard Guy Briggs
Date: Sat May 12 2018 - 21:59:57 EST


The audit-related parameters in struct task_struct should ideally be
collected together and accessed through a standard audit API.

Collect the existing loginuid, sessionid and audit_context together in a
new struct audit_task_info called "audit" in struct task_struct.

See: https://github.com/linux-audit/audit-kernel/issues/81

Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
---
MAINTAINERS | 2 +-
include/linux/audit.h | 10 +++++-----
include/linux/audit_task.h | 31 +++++++++++++++++++++++++++++++
include/linux/sched.h | 6 ++----
init/init_task.c | 7 +++++--
kernel/auditsc.c | 6 +++---
6 files changed, 47 insertions(+), 15 deletions(-)
create mode 100644 include/linux/audit_task.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 0a1410d..8c7992d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2510,7 +2510,7 @@ L: linux-audit@xxxxxxxxxx (moderated for non-subscribers)
W: https://github.com/linux-audit
T: git git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit.git
S: Supported
-F: include/linux/audit.h
+F: include/linux/audit*.h
F: include/uapi/linux/audit.h
F: kernel/audit*

diff --git a/include/linux/audit.h b/include/linux/audit.h
index f7973e4..6d599b6 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -237,11 +237,11 @@ extern void __audit_inode_child(struct inode *parent,

static inline void audit_set_context(struct task_struct *task, struct audit_context *ctx)
{
- task->audit_context = ctx;
+ task->audit.ctx = ctx;
}
static inline struct audit_context *audit_context(void)
{
- return current->audit_context;
+ return current->audit.ctx;
}
static inline bool audit_dummy_context(void)
{
@@ -250,7 +250,7 @@ static inline bool audit_dummy_context(void)
}
static inline void audit_free(struct task_struct *task)
{
- if (unlikely(task->audit_context))
+ if (unlikely(task->audit.ctx))
__audit_free(task);
}
static inline void audit_syscall_entry(int major, unsigned long a0,
@@ -330,12 +330,12 @@ extern int auditsc_get_stamp(struct audit_context *ctx,

static inline kuid_t audit_get_loginuid(struct task_struct *tsk)
{
- return tsk->loginuid;
+ return tsk->audit.loginuid;
}

static inline unsigned int audit_get_sessionid(struct task_struct *tsk)
{
- return tsk->sessionid;
+ return tsk->audit.sessionid;
}

extern void __audit_ipc_obj(struct kern_ipc_perm *ipcp);
diff --git a/include/linux/audit_task.h b/include/linux/audit_task.h
new file mode 100644
index 0000000..d4b3a20
--- /dev/null
+++ b/include/linux/audit_task.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* audit_task.h -- definition of audit_task_info structure
+ *
+ * Copyright 2018 Red Hat Inc., Raleigh, North Carolina.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Written by Richard Guy Briggs <rgb@xxxxxxxxxx>
+ *
+ */
+
+#ifndef _LINUX_AUDIT_TASK_H_
+#define _LINUX_AUDIT_TASK_H_
+
+struct audit_context;
+struct audit_task_info {
+ kuid_t loginuid;
+ unsigned int sessionid;
+ struct audit_context *ctx;
+};
+
+#endif
diff --git a/include/linux/sched.h b/include/linux/sched.h
index b3d697f..b58eca0 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -27,9 +27,9 @@
#include <linux/signal_types.h>
#include <linux/mm_types_task.h>
#include <linux/task_io_accounting.h>
+#include <linux/audit_task.h>

/* task_struct member predeclarations (sorted alphabetically): */
-struct audit_context;
struct backing_dev_info;
struct bio_list;
struct blk_plug;
@@ -832,10 +832,8 @@ struct task_struct {

struct callback_head *task_works;

- struct audit_context *audit_context;
#ifdef CONFIG_AUDITSYSCALL
- kuid_t loginuid;
- unsigned int sessionid;
+ struct audit_task_info audit;
#endif
struct seccomp seccomp;

diff --git a/init/init_task.c b/init/init_task.c
index 74f60ba..d33260d 100644
--- a/init/init_task.c
+++ b/init/init_task.c
@@ -119,8 +119,11 @@ struct task_struct init_task
.thread_group = LIST_HEAD_INIT(init_task.thread_group),
.thread_node = LIST_HEAD_INIT(init_signals.thread_head),
#ifdef CONFIG_AUDITSYSCALL
- .loginuid = INVALID_UID,
- .sessionid = AUDIT_SID_UNSET,
+ .audit = {
+ .loginuid = INVALID_UID,
+ .sessionid = AUDIT_SID_UNSET,
+ .ctx = NULL,
+ },
#endif
#ifdef CONFIG_PERF_EVENTS
.perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex),
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index d441d68..4c1fd18 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -836,7 +836,7 @@ static inline struct audit_context *audit_take_context(struct task_struct *tsk,
int return_valid,
long return_code)
{
- struct audit_context *context = tsk->audit_context;
+ struct audit_context *context = tsk->audit.ctx;

if (!context)
return NULL;
@@ -2066,8 +2066,8 @@ int audit_set_loginuid(kuid_t loginuid)
sessionid = (unsigned int)atomic_inc_return(&session_id);
}

- task->sessionid = sessionid;
- task->loginuid = loginuid;
+ task->audit.sessionid = sessionid;
+ task->audit.loginuid = loginuid;
out:
audit_log_set_loginuid(oldloginuid, loginuid, oldsessionid, sessionid, rc);
return rc;
--
1.8.3.1