[PATCH 5.4 19/92] tracing/uprobe: Fix uprobe_perf_open probes iteration

[Greg Kroah-Hartman]

From: Jiri Olsa <jolsa@xxxxxxxxxx>

commit 1880ed71ce863318c1ce93bf324876fb5f92854f upstream.

Add missing 'tu' variable initialization in the probes loop,
otherwise the head 'tu' is used instead of added probes.

Link: https://lkml.kernel.org/r/20211123142801.182530-1-jolsa@xxxxxxxxxx

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 99c9a923e97a ("tracing/uprobe: Fix double perf_event linking on multiprobe uprobe")
Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 kernel/trace/trace_uprobe.c |    1 +
 1 file changed, 1 insertion(+)

--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -1299,6 +1299,7 @@ static int uprobe_perf_open(struct trace
 		return 0;
 
 	list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+		tu = container_of(pos, struct trace_uprobe, tp);
 		err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true);
 		if (err) {
 			uprobe_perf_close(call, event);