[PATCH 6/8] tracing/probe: Check the size of argument name and body

[Steven Rostedt]

From: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

Check the size of argument name and expression is not 0
and smaller than maximum length.

Link: 155253783029.14922.12650939303827581096.stgit@devnote2">http://lkml.kernel.org/r/155253783029.14922.12650939303827581096.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
 kernel/trace/trace_probe.c | 2 ++
 kernel/trace/trace_probe.h | 1 +
 2 files changed, 3 insertions(+)

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 0dc13bff2847..bf9d3d7e0c9d 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -554,6 +554,8 @@ int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, char *arg,
 
 	body = strchr(arg, '=');
 	if (body) {
+		if (body - arg > MAX_ARG_NAME_LEN || body == arg)
+			return -EINVAL;
 		parg->name = kmemdup_nul(arg, body - arg, GFP_KERNEL);
 		body++;
 	} else {
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 8a63f8bc01bc..2177c206de15 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -32,6 +32,7 @@
 #define MAX_TRACE_ARGS		128
 #define MAX_ARGSTR_LEN		63
 #define MAX_ARRAY_LEN		64
+#define MAX_ARG_NAME_LEN	32
 #define MAX_STRING_SIZE		PATH_MAX
 
 /* Reserved field names */
-- 
2.20.1