From: Divya Indi divya.indi@oracle.com
[ Upstream commit 953ae45a0c25e09428d4a03d7654f97ab8a36647 ]
As part of commit f45d1225adb0 ("tracing: Kernel access to Ftrace instances") we exported certain functions. Here, we are adding some additional NULL checks to ensure safe usage by users of these APIs.
Link: http://lkml.kernel.org/r/1565805327-579-4-git-send-email-divya.indi@oracle.c...
Signed-off-by: Divya Indi divya.indi@oracle.com Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/trace/trace.c | 3 +++ kernel/trace/trace_events.c | 2 ++ 2 files changed, 5 insertions(+)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 95ede1f7ffdf3..22759f5607192 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3035,6 +3035,9 @@ int trace_array_printk(struct trace_array *tr, if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0;
+ if (!tr) + return -ENOENT; + va_start(ap, fmt); ret = trace_array_vprintk(tr, ip, fmt, ap); va_end(ap); diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index e72a44ecb81da..d69c79ac97986 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -799,6 +799,8 @@ static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set) char *event = NULL, *sub = NULL, *match; int ret;
+ if (!tr) + return -ENOENT; /* * The buf format can be <subsystem>:<event-name> * *:<event-name> means any event by that name.