[for-linus][PATCH 08/15] tracing: Have event inject files inc the trace array ref count

[Steven Rostedt]

From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>

The event inject files add events for a specific trace array. For an
instance, if the file is opened and the instance is deleted, reading or
writing to the file will cause a use after free.

Up the ref count of the trace_array when a event inject file is opened.

Link: https://lkml.kernel.org/r/20230907024804.292337868@xxxxxxxxxxx
Link: https://lore.kernel.org/all/1cb3aee2-19af-c472-e265-05176fe9bd84@xxxxxxxxxx/

Cc: stable@xxxxxxxxxxxxxxx
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Zheng Yejian <zhengyejian1@xxxxxxxxxx>
Fixes: 6c3edaf9fd6a ("tracing: Introduce trace event injection")
Tested-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
Tested-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
 kernel/trace/trace_events_inject.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/trace/trace_events_inject.c b/kernel/trace/trace_events_inject.c
index abe805d471eb..8650562bdaa9 100644
--- a/kernel/trace/trace_events_inject.c
+++ b/kernel/trace/trace_events_inject.c
@@ -328,7 +328,8 @@ event_inject_read(struct file *file, char __user *buf, size_t size,
 }
 
 const struct file_operations event_inject_fops = {
-	.open = tracing_open_generic,
+	.open = tracing_open_file_tr,
 	.read = event_inject_read,
 	.write = event_inject_write,
+	.release = tracing_release_file_tr,
 };
-- 
2.40.1