uprobes: Fix return value in error handling path

commit fa44063f9ef163c3a4c8d8c0465bb8a056b42035 upstream.

When wrong argument is passed into uprobe_events it does not return
an error:

[root@jovi tracing]# echo 'p:myprobe /bin/bash' > uprobe_events
[root@jovi tracing]#

The proper response is:

[root@jovi tracing]# echo 'p:myprobe /bin/bash' > uprobe_events
-bash: echo: write error: Invalid argument

Link: http://lkml.kernel.org/r/51B964FF.5000106@huawei.com

Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: <srikar@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 32494fb0ee64..d5d0cd368a56 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -283,8 +283,10 @@ static int create_trace_uprobe(int argc, char **argv)
                 return -EINVAL;
         }
         arg = strchr(argv[1], ':');
-        if (!arg)
+        if (!arg) {
+                ret = -EINVAL;
                 goto fail_address_parse;
+        }
 
         *arg++ = '\0';
         filename = argv[1];