1 files changed, 34 insertions, 11 deletions

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 1b31c130d034..00d79df03e76 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -241,6 +241,10 @@ struct audit_context {
                         pid_t                   pid;
                         struct audit_cap_data   cap;
                 } capset;
+                struct {
+                        int                     fd;
+                        int                     flags;
+                } mmap;
         };
         int fds[2];
 
@@ -439,17 +443,25 @@ static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
 
 /* Determine if any context name data matches a rule's watch data */
 /* Compare a task_struct with an audit_rule.  Return 1 on match, 0
- * otherwise. */
+ * otherwise.
+ *
+ * If task_creation is true, this is an explicit indication that we are
+ * filtering a task rule at task creation time.  This and tsk == current are
+ * the only situations where tsk->cred may be accessed without an rcu read lock.
+ */
 static int audit_filter_rules(struct task_struct *tsk,
                               struct audit_krule *rule,
                               struct audit_context *ctx,
                               struct audit_names *name,
-                              enum audit_state *state)
+                              enum audit_state *state,
+                              bool task_creation)
 {
-        const struct cred *cred = get_task_cred(tsk);
+        const struct cred *cred;
         int i, j, need_sid = 1;
         u32 sid;
 
+        cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
+
         for (i = 0; i < rule->field_count; i++) {
                 struct audit_field *f = &rule->fields[i];
                 int result = 0;
@@ -633,10 +645,8 @@ static int audit_filter_rules(struct task_struct *tsk,
                         break;
                 }
 
-                if (!result) {
-                        put_cred(cred);
+                if (!result)
                         return 0;
-                }
         }
 
         if (ctx) {
@@ -652,7 +662,6 @@ static int audit_filter_rules(struct task_struct *tsk,
         case AUDIT_NEVER:    *state = AUDIT_DISABLED;       break;
         case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
         }
-        put_cred(cred);
         return 1;
 }
 
@@ -667,7 +676,8 @@ static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
 
         rcu_read_lock();
         list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
-                if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) {
+                if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
+                                       &state, true)) {
                         if (state == AUDIT_RECORD_CONTEXT)
                                 *key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
                         rcu_read_unlock();
@@ -701,7 +711,7 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk,
                 list_for_each_entry_rcu(e, list, list) {
                         if ((e->rule.mask[word] & bit) == bit &&
                             audit_filter_rules(tsk, &e->rule, ctx, NULL,
-                                               &state)) {
+                                               &state, false)) {
                                 rcu_read_unlock();
                                 ctx->current_state = state;
                                 return state;
@@ -739,7 +749,8 @@ void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
 
                 list_for_each_entry_rcu(e, list, list) {
                         if ((e->rule.mask[word] & bit) == bit &&
-                            audit_filter_rules(tsk, &e->rule, ctx, n, &state)) {
+                            audit_filter_rules(tsk, &e->rule, ctx, n,
+                                               &state, false)) {
                                 rcu_read_unlock();
                                 ctx->current_state = state;
                                 return;
@@ -1007,7 +1018,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 /*
  * to_send and len_sent accounting are very loose estimates.  We aren't
  * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
- * within about 500 bytes (next page boundry)
+ * within about 500 bytes (next page boundary)
  *
  * why snprintf?  an int is up to 12 digits long.  if we just assumed when
  * logging that a[%d]= was going to be 16 characters long we would be wasting
@@ -1305,6 +1316,10 @@ static void show_special(struct audit_context *context, int *call_panic)
                 audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
                 audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
                 break; }
+        case AUDIT_MMAP: {
+                audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
+                                 context->mmap.flags);
+                break; }
         }
         audit_log_end(ab);
 }
@@ -2476,6 +2491,14 @@ void __audit_log_capset(pid_t pid,
         context->type = AUDIT_CAPSET;
 }
 
+void __audit_mmap_fd(int fd, int flags)
+{
+        struct audit_context *context = current->audit_context;
+        context->mmap.fd = fd;
+        context->mmap.flags = flags;
+        context->type = AUDIT_MMAP;
+}
+
 /**
  * audit_core_dumps - record information about processes that end abnormally
  * @signr: signal value