tracing/filters: NIL-terminate user input filter
Make sure messages from user space are NIL-terminated strings,
otherwise we could dump random memory while reading filter file.
Try this:
# echo 'parent_comm ==' > events/sched/sched_process_fork/filter
# cat events/sched/sched_process_fork/filter
parent_comm == �
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Tom Zanussi <tzanussi@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <49E04C32.6060508@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 64ec4d2..054bc18 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -503,6 +503,7 @@
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
+ buf[cnt] = '\0';
pred = kzalloc(sizeof(*pred), GFP_KERNEL);
if (!pred)
@@ -569,6 +570,7 @@
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
+ buf[cnt] = '\0';
pred = kzalloc(sizeof(*pred), GFP_KERNEL);
if (!pred)