kernel/taskstats.c: add nla_nest_cancel() for failure processing between nla_nest_start() and nla_nest_end()

When failure occurs between nla_nest_start() and nla_nest_end(), we should
call nla_nest_cancel() to clean up related things.

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 2 deletions

diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index 145bb4d3bd4d..1db6808c494b 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -404,11 +404,15 @@ static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
         if (!na)
                 goto err;
 
-        if (nla_put(skb, type, sizeof(pid), &pid) < 0)
+        if (nla_put(skb, type, sizeof(pid), &pid) < 0) {
+                nla_nest_cancel(skb, na);
                 goto err;
+        }
         ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats));
-        if (!ret)
+        if (!ret) {
+                nla_nest_cancel(skb, na);
                 goto err;
+        }
         nla_nest_end(skb, na);
 
         return nla_data(ret);