tracing: fix incorrect tracer freeing when opening tracing pipe

euler inclusion
category: bugfix
bugzilla: 9292
CVE: NA
---------------------------

Commit d716ff71 ("tracing: Remove taking of trace_types_lock in
pipe files") use the current tracer instead of the copy in
tracing_open_pipe(), but it forget to remove the freeing sentence in
the error path.

Fixes: d716ff71 ("tracing: Remove taking of trace_types_lock in pipe files")
Signed-off-by: Nzhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: NLi Bin <huawei.libin@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

kernel/trace/trace.c

@@ -5604,7 +5604,6 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
 	return ret;
 
 fail:
-	kfree(iter->trace);
 	kfree(iter);
 	__trace_array_put(tr);
 	mutex_unlock(&trace_types_lock);