perf callchain: Check return value of add_child()

The create_child() in add_child() can return NULL in case of memory
allocation failure.  So check the return value and bail out.  The proper
error handling will be added later.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1455631723-17345-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 53c43eb..134d88b 100644 (file)
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -453,6 +453,9 @@ add_child(struct callchain_node *parent,
        struct callchain_node *new;
 
        new = create_child(parent, false);
+       if (new == NULL)
+               return NULL;
+
        fill_node(new, cursor);
 
        new->children_hit = 0;
@@ -524,6 +527,8 @@ split_add_child(struct callchain_node *parent,
 
                node = callchain_cursor_current(cursor);
                new = add_child(parent, cursor, period);
+               if (new == NULL)
+                       return;
 
                /*
                 * This is second child since we moved parent's children
@@ -585,6 +590,9 @@ append_chain_children(struct callchain_node *root,
        }
        /* nothing in children, add to the current node */
        rnode = add_child(root, cursor, period);
+       if (rnode == NULL)
+               return;
+
        rb_link_node(&rnode->rb_node_in, parent, p);
        rb_insert_color(&rnode->rb_node_in, &root->rb_root_in);