audit: use inline function to get audit context

Recognizing that the audit context is an internal audit value, use an
access function to retrieve the audit context pointer for the task
rather than reaching directly into the task struct to get it.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: merge fuzz in auditsc.c and selinuxfs.c, checkpatch.pl fixes]
Signed-off-by: Paul Moore <paul@paul-moore.com>

include/linux/audit.h

@@ -237,9 +237,14 @@ extern void audit_seccomp_actions_logged(const char *names,
 					 const char *old_names, int res);
 extern void __audit_ptrace(struct task_struct *t);
 
+static inline struct audit_context *audit_context(void)
+{
+	return current->audit_context;
+}
+
 static inline bool audit_dummy_context(void)
 {
-	void *p = current->audit_context;
+	void *p = audit_context();
 	return !p || *(int *)p;
 }
 static inline void audit_free(struct task_struct *task)
@@ -251,12 +256,12 @@ static inline void audit_syscall_entry(int major, unsigned long a0,
 				       unsigned long a1, unsigned long a2,
 				       unsigned long a3)
 {
-	if (unlikely(current->audit_context))
+	if (unlikely(audit_context()))
 		__audit_syscall_entry(major, a0, a1, a2, a3);
 }
 static inline void audit_syscall_exit(void *pt_regs)
 {
-	if (unlikely(current->audit_context)) {
+	if (unlikely(audit_context())) {
 		int success = is_syscall_success(pt_regs);
 		long return_code = regs_return_value(pt_regs);
 
@@ -464,6 +469,10 @@ static inline bool audit_dummy_context(void)
 {
 	return true;
 }
+static inline struct audit_context *audit_context(void)
+{
+	return NULL;
+}
 static inline struct filename *audit_reusename(const __user char *name)
 {
 	return NULL;

include/net/xfrm.h

@@ -736,7 +736,7 @@ static inline struct audit_buffer *xfrm_audit_start(const char *op)
 
 	if (audit_enabled == 0)
 		return NULL;
-	audit_buf = audit_log_start(current->audit_context, GFP_ATOMIC,
+	audit_buf = audit_log_start(audit_context(), GFP_ATOMIC,
 				    AUDIT_MAC_IPSEC_EVENT);
 	if (audit_buf == NULL)
 		return NULL;

kernel/audit.c

@@ -1099,8 +1099,7 @@ static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature
 
 	if (audit_enabled == AUDIT_OFF)
 		return;
-	ab = audit_log_start(current->audit_context,
-			     GFP_KERNEL, AUDIT_FEATURE_CHANGE);
+	ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_FEATURE_CHANGE);
 	if (!ab)
 		return;
 	audit_log_task_info(ab, current);
@@ -2317,8 +2316,7 @@ void audit_log_link_denied(const char *operation)
 		return;
 
 	/* Generate AUDIT_ANOM_LINK with subject, operation, outcome. */
-	ab = audit_log_start(current->audit_context, GFP_KERNEL,
-			     AUDIT_ANOM_LINK);
+	ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_ANOM_LINK);
 	if (!ab)
 		return;
 	audit_log_format(ab, "op=%s", operation);

kernel/audit_watch.c

@@ -274,7 +274,7 @@ static void audit_update_watch(struct audit_parent *parent,
 		/* If the update involves invalidating rules, do the inode-based
 		 * filtering now, so we don't omit records. */
 		if (invalidating && !audit_dummy_context())
-			audit_filter_inodes(current, current->audit_context);
+			audit_filter_inodes(current, audit_context());
 
 		/* updating ino will likely change which audit_hash_list we
 		 * are on so we need a new watch for the new list */

kernel/auditsc.c

@@ -1509,8 +1509,7 @@ void __audit_free(struct task_struct *tsk)
 void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
 			   unsigned long a3, unsigned long a4)
 {
-	struct task_struct *tsk = current;
-	struct audit_context *context = tsk->audit_context;
+	struct audit_context *context = audit_context();
 	enum audit_state     state;
 
 	if (!audit_enabled || !context)
@@ -1525,7 +1524,7 @@ void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
 	context->dummy = !audit_n_rules;
 	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
 		context->prio = 0;
-		if (auditd_test_task(tsk))
+		if (auditd_test_task(current))
 			return;
 	}
 
@@ -1563,12 +1562,12 @@ void __audit_syscall_exit(int success, long return_code)
 	else
 		success = AUDITSC_FAILURE;
 
-	context = audit_take_context(tsk, success, return_code);
+	context = audit_take_context(current, success, return_code);
 	if (!context)
 		return;
 
 	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
-		audit_log_exit(context, tsk);
+		audit_log_exit(context, current);
 
 	context->in_syscall = 0;
 	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
@@ -1602,7 +1601,7 @@ static inline void handle_one(const struct inode *inode)
 	int count;
 	if (likely(!inode->i_fsnotify_marks))
 		return;
-	context = current->audit_context;
+	context = audit_context();
 	p = context->trees;
 	count = context->tree_count;
 	rcu_read_lock();
@@ -1633,7 +1632,7 @@ static void handle_path(const struct dentry *dentry)
 	unsigned long seq;
 	int count;
 
-	context = current->audit_context;
+	context = audit_context();
 	p = context->trees;
 	count = context->tree_count;
 retry:
@@ -1715,7 +1714,7 @@ static struct audit_names *audit_alloc_name(struct audit_context *context,
 struct filename *
 __audit_reusename(const __user char *uptr)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	struct audit_names *n;
 
 	list_for_each_entry(n, &context->names_list, list) {
@@ -1738,7 +1737,7 @@ __audit_reusename(const __user char *uptr)
  */
 void __audit_getname(struct filename *name)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	struct audit_names *n;
 
 	if (!context->in_syscall)
@@ -1766,7 +1765,7 @@ void __audit_getname(struct filename *name)
 void __audit_inode(struct filename *name, const struct dentry *dentry,
 		   unsigned int flags)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	struct inode *inode = d_backing_inode(dentry);
 	struct audit_names *n;
 	bool parent = flags & AUDIT_INODE_PARENT;
@@ -1865,7 +1864,7 @@ void __audit_inode_child(struct inode *parent,
 			 const struct dentry *dentry,
 			 const unsigned char type)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	struct inode *inode = d_backing_inode(dentry);
 	const char *dname = dentry->d_name.name;
 	struct audit_names *n, *found_parent = NULL, *found_child = NULL;
@@ -2084,7 +2083,7 @@ int audit_set_loginuid(kuid_t loginuid)
  */
 void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 
 	if (attr)
 		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
@@ -2108,7 +2107,7 @@ void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
 void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
 			const struct timespec64 *abs_timeout)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	struct timespec64 *p = &context->mq_sendrecv.abs_timeout;
 
 	if (abs_timeout)
@@ -2132,7 +2131,7 @@ void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
 
 void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 
 	if (notification)
 		context->mq_notify.sigev_signo = notification->sigev_signo;
@@ -2151,7 +2150,7 @@ void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
  */
 void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	context->mq_getsetattr.mqdes = mqdes;
 	context->mq_getsetattr.mqstat = *mqstat;
 	context->type = AUDIT_MQ_GETSETATTR;
@@ -2164,7 +2163,7 @@ void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
  */
 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	context->ipc.uid = ipcp->uid;
 	context->ipc.gid = ipcp->gid;
 	context->ipc.mode = ipcp->mode;
@@ -2184,7 +2183,7 @@ void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
  */
 void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 
 	context->ipc.qbytes = qbytes;
 	context->ipc.perm_uid = uid;
@@ -2195,7 +2194,7 @@ void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mo
 
 void __audit_bprm(struct linux_binprm *bprm)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 
 	context->type = AUDIT_EXECVE;
 	context->execve.argc = bprm->argc;
@@ -2210,7 +2209,7 @@ void __audit_bprm(struct linux_binprm *bprm)
  */
 int __audit_socketcall(int nargs, unsigned long *args)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 
 	if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
 		return -EINVAL;
@@ -2228,7 +2227,7 @@ int __audit_socketcall(int nargs, unsigned long *args)
  */
 void __audit_fd_pair(int fd1, int fd2)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	context->fds[0] = fd1;
 	context->fds[1] = fd2;
 }
@@ -2242,7 +2241,7 @@ void __audit_fd_pair(int fd1, int fd2)
  */
 int __audit_sockaddr(int len, void *a)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 
 	if (!context->sockaddr) {
 		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
@@ -2258,7 +2257,7 @@ int __audit_sockaddr(int len, void *a)
 
 void __audit_ptrace(struct task_struct *t)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 
 	context->target_pid = task_tgid_nr(t);
 	context->target_auid = audit_get_loginuid(t);
@@ -2279,19 +2278,18 @@ void __audit_ptrace(struct task_struct *t)
 int audit_signal_info(int sig, struct task_struct *t)
 {
 	struct audit_aux_data_pids *axp;
-	struct task_struct *tsk = current;
-	struct audit_context *ctx = tsk->audit_context;
+	struct audit_context *ctx = audit_context();
 	kuid_t uid = current_uid(), t_uid = task_uid(t);
 
 	if (auditd_test_task(t) &&
 	    (sig == SIGTERM || sig == SIGHUP ||
 	     sig == SIGUSR1 || sig == SIGUSR2)) {
-		audit_sig_pid = task_tgid_nr(tsk);
-		if (uid_valid(tsk->loginuid))
-			audit_sig_uid = tsk->loginuid;
+		audit_sig_pid = task_tgid_nr(current);
+		if (uid_valid(current->loginuid))
+			audit_sig_uid = current->loginuid;
 		else
 			audit_sig_uid = uid;
-		security_task_getsecid(tsk, &audit_sig_sid);
+		security_task_getsecid(current, &audit_sig_sid);
 	}
 
 	if (!audit_signals || audit_dummy_context())
@@ -2347,7 +2345,7 @@ int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
 			   const struct cred *new, const struct cred *old)
 {
 	struct audit_aux_data_bprm_fcaps *ax;
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	struct cpu_vfs_cap_data vcaps;
 
 	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
@@ -2387,7 +2385,7 @@ int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
  */
 void __audit_log_capset(const struct cred *new, const struct cred *old)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	context->capset.pid = task_tgid_nr(current);
 	context->capset.cap.effective   = new->cap_effective;
 	context->capset.cap.inheritable = new->cap_effective;
@@ -2398,15 +2396,15 @@ void __audit_log_capset(const struct cred *new, const struct cred *old)
 
 void __audit_mmap_fd(int fd, int flags)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 	context->mmap.fd = fd;
 	context->mmap.flags = flags;
 	context->type = AUDIT_MMAP;
 }
 
 void __audit_log_kern_module(char *name)
 {
-	struct audit_context *context = current->audit_context;
+	struct audit_context *context = audit_context();
 
 	context->module.name = kmalloc(strlen(name) + 1, GFP_KERNEL);
 	strcpy(context->module.name, name);
@@ -2415,7 +2413,7 @@ void __audit_log_kern_module(char *name)
 
 void __audit_fanotify(unsigned int response)
 {
-	audit_log(current->audit_context, GFP_KERNEL,
+	audit_log(audit_context(), GFP_KERNEL,
 		AUDIT_FANOTIFY,	"resp=%u", response);
 }
 
@@ -2514,7 +2512,7 @@ void audit_seccomp_actions_logged(const char *names, const char *old_names,
 
 struct list_head *audit_killed_trees(void)
 {
-	struct audit_context *ctx = current->audit_context;
+	struct audit_context *ctx = audit_context();
 	if (likely(!ctx || !ctx->in_syscall))
 		return NULL;
 	return &ctx->killed_trees;

net/bridge/netfilter/ebtables.c

@@ -1062,7 +1062,7 @@ static int do_replace_finish(struct net *net, struct ebt_replace *repl,
 
 #ifdef CONFIG_AUDIT
 	if (audit_enabled) {
-		audit_log(current->audit_context, GFP_KERNEL,
+		audit_log(audit_context(), GFP_KERNEL,
 			  AUDIT_NETFILTER_CFG,
 			  "table=%s family=%u entries=%u",
 			  repl->name, AF_BRIDGE, repl->nentries);

net/core/dev.c

@@ -6749,15 +6749,15 @@ static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
 			dev->flags & IFF_PROMISC ? "entered" : "left");
 		if (audit_enabled) {
 			current_uid_gid(&uid, &gid);
-			audit_log(current->audit_context, GFP_ATOMIC,
-				AUDIT_ANOM_PROMISCUOUS,
-				"dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
-				dev->name, (dev->flags & IFF_PROMISC),
-				(old_flags & IFF_PROMISC),
-				from_kuid(&init_user_ns, audit_get_loginuid(current)),
-				from_kuid(&init_user_ns, uid),
-				from_kgid(&init_user_ns, gid),
-				audit_get_sessionid(current));
+			audit_log(audit_context(), GFP_ATOMIC,
+				  AUDIT_ANOM_PROMISCUOUS,
+				  "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
+				  dev->name, (dev->flags & IFF_PROMISC),
+				  (old_flags & IFF_PROMISC),
+				  from_kuid(&init_user_ns, audit_get_loginuid(current)),
+				  from_kuid(&init_user_ns, uid),
+				  from_kgid(&init_user_ns, gid),
+				  audit_get_sessionid(current));
 		}
 
 		dev_change_rx_flags(dev, IFF_PROMISC);

net/netfilter/x_tables.c

@@ -1414,7 +1414,7 @@ xt_replace_table(struct xt_table *table,
 
 #ifdef CONFIG_AUDIT
 	if (audit_enabled) {
-		audit_log(current->audit_context, GFP_KERNEL,
+		audit_log(audit_context(), GFP_KERNEL,
 			  AUDIT_NETFILTER_CFG,
 			  "table=%s family=%u entries=%u",
 			  table->name, table->af, private->number);

net/netlabel/netlabel_user.c

@@ -104,7 +104,7 @@ struct audit_buffer *netlbl_audit_start_common(int type,
 	if (audit_enabled == 0)
 		return NULL;
 
-	audit_buf = audit_log_start(current->audit_context, GFP_ATOMIC, type);
+	audit_buf = audit_log_start(audit_context(), GFP_ATOMIC, type);
 	if (audit_buf == NULL)
 		return NULL;