From: Divya Indi <divya.indi@oracle.com>
Date: Wed, 14 Aug 2019 17:55:25 +0000 (-0700)
Subject: tracing: Adding NULL checks for trace_array descriptor pointer
X-Git-Tag: v5.10.7~3659^2~35
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=953ae45a0c25e09428d4a03d7654f97ab8a36647;p=platform%2Fkernel%2Flinux-rpi.git

tracing: Adding NULL checks for trace_array descriptor pointer

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.com

Signed-off-by: Divya Indi <divya.indi@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index fa4f742..79fe4d6 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3297,6 +3297,9 @@ 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 fba87d1..2a3ac23 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -793,6 +793,8 @@ 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.