audit: fix netlink portid naming and types

Normally, netlink ports use the PID of the userspace process as the port ID.
If the PID is already in use by a port, the kernel will allocate another port
ID to avoid conflict.  Re-name all references to netlink ports from pid to
portid to reflect this reality and avoid confusion with actual PIDs.  Ports
use the __u32 type, so re-type all portids accordingly.

(This patch is very similar to ebiederman's 5deadd69)

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Eric Paris <eparis@redhat.com>

4 files changed, 31 insertions, 29 deletions

diff --git a/include/linux/audit.h b/include/linux/audit.h
index c9a66c6f1307..9185bfa1c78b 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -461,7 +461,7 @@ extern int		    audit_update_lsm_rules(void);
                                 /* Private API (for audit.c only) */
 extern int audit_filter_user(int type);
 extern int audit_filter_type(int type);
-extern int  audit_receive_filter(int type, int pid, int seq,
+extern int  audit_receive_filter(int type, __u32 portid, int seq,
                                 void *data, size_t datasz);
 extern int audit_enabled;
 #else /* CONFIG_AUDIT */
diff --git a/kernel/audit.c b/kernel/audit.c
index 906ae5a0233a..3d3747be7c52 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -93,7 +93,7 @@ static int	audit_failure = AUDIT_FAIL_PRINTK;
  * the portid to use to send netlink messages to that process.
  */
 int             audit_pid;
-static int      audit_nlk_portid;
+static __u32    audit_nlk_portid;
 
 /* If audit_rate_limit is non-zero, limit the rate of sending audit records
  * to that number per second.  This prevents DoS attacks, but results in
@@ -175,15 +175,15 @@ struct audit_buffer {
 };
 
 struct audit_reply {
-        int pid;
+        __u32 portid;
         struct sk_buff *skb;
 };
 
-static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
+static void audit_set_portid(struct audit_buffer *ab, __u32 portid)
 {
         if (ab) {
                 struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
-                nlh->nlmsg_pid = pid;
+                nlh->nlmsg_pid = portid;
         }
 }
 
@@ -482,7 +482,7 @@ static int kauditd_thread(void *dummy)
 int audit_send_list(void *_dest)
 {
         struct audit_netlink_list *dest = _dest;
-        int pid = dest->pid;
+        __u32 portid = dest->portid;
         struct sk_buff *skb;
 
         /* wait for parent to finish and send an ACK */
@@ -490,14 +490,14 @@ int audit_send_list(void *_dest)
         mutex_unlock(&audit_cmd_mutex);
 
         while ((skb = __skb_dequeue(&dest->q)) != NULL)
-                netlink_unicast(audit_sock, skb, pid, 0);
+                netlink_unicast(audit_sock, skb, portid, 0);
 
         kfree(dest);
 
         return 0;
 }
 
-struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
+struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, int done,
                                  int multi, const void *payload, int size)
 {
         struct sk_buff  *skb;
@@ -510,7 +510,7 @@ struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
         if (!skb)
                 return NULL;
 
-        nlh     = nlmsg_put(skb, pid, seq, t, size, flags);
+        nlh     = nlmsg_put(skb, portid, seq, t, size, flags);
         if (!nlh)
                 goto out_kfree_skb;
         data = nlmsg_data(nlh);
@@ -531,13 +531,13 @@ static int audit_send_reply_thread(void *arg)
 
         /* Ignore failure. It'll only happen if the sender goes away,
            because our timeout is set to infinite. */
-        netlink_unicast(audit_sock, reply->skb, reply->pid, 0);
+        netlink_unicast(audit_sock, reply->skb, reply->portid, 0);
         kfree(reply);
         return 0;
 }
 /**
  * audit_send_reply - send an audit reply message via netlink
- * @pid: process id to send reply to
+ * @portid: netlink port to which to send reply
  * @seq: sequence number
  * @type: audit message type
  * @done: done (last) flag
@@ -545,11 +545,11 @@ static int audit_send_reply_thread(void *arg)
  * @payload: payload data
  * @size: payload size
  *
- * Allocates an skb, builds the netlink message, and sends it to the pid.
+ * Allocates an skb, builds the netlink message, and sends it to the port id.
  * No failure notifications.
  */
-static void audit_send_reply(int pid, int seq, int type, int done, int multi,
-                             const void *payload, int size)
+static void audit_send_reply(__u32 portid, int seq, int type, int done,
+                             int multi, const void *payload, int size)
 {
         struct sk_buff *skb;
         struct task_struct *tsk;
@@ -559,11 +559,11 @@ static void audit_send_reply(int pid, int seq, int type, int done, int multi,
         if (!reply)
                 return;
 
-        skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
+        skb = audit_make_reply(portid, seq, type, done, multi, payload, size);
         if (!skb)
                 goto out;
 
-        reply->pid = pid;
+        reply->portid = portid;
         reply->skb = skb;
 
         tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
@@ -839,7 +839,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                                         size--;
                                 audit_log_n_untrustedstring(ab, data, size);
                         }
-                        audit_set_pid(ab, NETLINK_CB(skb).portid);
+                        audit_set_portid(ab, NETLINK_CB(skb).portid);
                         audit_log_end(ab);
                 }
                 break;
diff --git a/kernel/audit.h b/kernel/audit.h
index b779642b29af..c7282444caea 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -240,13 +240,13 @@ extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right);
 extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right);
 extern int parent_len(const char *path);
 extern int audit_compare_dname_path(const char *dname, const char *path, int plen);
-extern struct sk_buff *     audit_make_reply(int pid, int seq, int type,
-                                             int done, int multi,
-                                             const void *payload, int size);
+extern struct sk_buff *audit_make_reply(__u32 portid, int seq, int type,
+                                        int done, int multi,
+                                        const void *payload, int size);
 extern void                 audit_panic(const char *message);
 
 struct audit_netlink_list {
-        int pid;
+        __u32 portid;
         struct sk_buff_head q;
 };
 
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 51f3fd4c1ed3..08f7f7bef26c 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -972,7 +972,7 @@ out:
 }
 
 /* List rules using struct audit_rule_data. */
-static void audit_list_rules(int pid, int seq, struct sk_buff_head *q)
+static void audit_list_rules(__u32 portid, int seq, struct sk_buff_head *q)
 {
         struct sk_buff *skb;
         struct audit_krule *r;
@@ -987,14 +987,15 @@ static void audit_list_rules(int pid, int seq, struct sk_buff_head *q)
                         data = audit_krule_to_data(r);
                         if (unlikely(!data))
                                 break;
-                        skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1,
-                                         data, sizeof(*data) + data->buflen);
+                        skb = audit_make_reply(portid, seq, AUDIT_LIST_RULES,
+                                               0, 1, data,
+                                               sizeof(*data) + data->buflen);
                         if (skb)
                                 skb_queue_tail(q, skb);
                         kfree(data);
                 }
         }
-        skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0);
+        skb = audit_make_reply(portid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0);
         if (skb)
                 skb_queue_tail(q, skb);
 }
@@ -1024,12 +1025,13 @@ static void audit_log_rule_change(char *action, struct audit_krule *rule, int re
 /**
  * audit_receive_filter - apply all rules to the specified message type
  * @type: audit message type
- * @pid: target pid for netlink audit messages
+ * @portid: target port id for netlink audit messages
  * @seq: netlink audit message sequence (serial) number
  * @data: payload data
  * @datasz: size of payload data
  */
-int audit_receive_filter(int type, int pid, int seq, void *data, size_t datasz)
+int audit_receive_filter(int type, __u32 portid, int seq, void *data,
+                         size_t datasz)
 {
         struct task_struct *tsk;
         struct audit_netlink_list *dest;
@@ -1047,11 +1049,11 @@ int audit_receive_filter(int type, int pid, int seq, void *data, size_t datasz)
                 dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL);
                 if (!dest)
                         return -ENOMEM;
-                dest->pid = pid;
+                dest->portid = portid;
                 skb_queue_head_init(&dest->q);
 
                 mutex_lock(&audit_filter_mutex);
-                audit_list_rules(pid, seq, &dest->q);
+                audit_list_rules(portid, seq, &dest->q);
                 mutex_unlock(&audit_filter_mutex);
 
                 tsk = kthread_run(audit_send_list, dest, "audit_send_list");