From: Steven Rostedt The system enabling of events uses the same code as the set_event file. It passes in the name of the system to the parser and that will enable all the events that has that system as a name. The problem is that it will also enable events with the same name as the system. If you have system name foo, and system name bar, but within the system bar, there exists an event called foo. By setting the system name foo, you will also be enabling the event foo in the system bar. This is not an expected result. The solution is to pass in "foo:*", which will only enable the system foo and not events called foo. [ Impact: prevent accidental enabling of events with same name as a system ] Reported-by: Li Zefan Signed-off-by: Steven Rostedt --- kernel/trace/trace_events.c | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 87feb01..8d0fae3 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -509,9 +509,11 @@ system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, return -EINVAL; } - command = kstrdup(system, GFP_KERNEL); + /* +3 for the ":*\0" */ + command = kmalloc(strlen(system)+3, GFP_KERNEL); if (!command) return -ENOMEM; + sprintf(command, "%s:*", system); ret = ftrace_set_clr_event(command, val); if (ret) @@ -1179,7 +1181,7 @@ static __init int event_trace_init(void) &ftrace_show_header_fops); trace_create_file("enable", 0644, d_events, - "*:*", &ftrace_system_enable_fops); + "*", &ftrace_system_enable_fops); for_each_event(call, __start_ftrace_events, __stop_ftrace_events) { /* The linker may leave blanks */ -- 1.6.2.4 -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/