This is a note to let you know that I've just added the patch titled
tracing: Adding NULL checks for trace_array descriptor pointer
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tracing-adding-null-checks-for-trace_array-descripto.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 8e310b89ee593b349efb51b85592939aaa34ddf9
Author: Divya Indi <divya.indi@xxxxxxxxxx>
Date: Wed Aug 14 10:55:25 2019 -0700
tracing: Adding NULL checks for trace_array descriptor pointer
[ 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@xxxxxxxxxx
Signed-off-by: Divya Indi <divya.indi@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index b2fb25aefb2fc..67cee2774a6b8 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2600,6 +2600,9 @@ 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 af969f753e5e9..5bf072e437c41 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -790,6 +790,8 @@ 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.
