Merge tag 'trace-v4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This adds three fixes for the tracing code.

  The first is a bug when ftrace_dump_on_oops is triggered in atomic
  context and function graph tracer is the tracer that is being
  reported.

  The second fix is bad parsing of the trace_events from the kernel
  command line, where it would ignore specific events if the system name
  is used with defining the event(it enables all events within the
  system).

  The last one is a fix to the TRACE_DEFINE_ENUM(), where a check was
  missing to see if the ptr was incremented to the end of the string,
  but the loop increments it again and can miss the nul delimiter to
  stop processing"

* tag 'trace-v4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix possible out of bounds memory access when parsing enums
  tracing: Fix incorrect enabling of trace events by boot cmdline
  tracing: Handle ftrace_dump() atomic context in graph_trace_open()

2 files changed, 20 insertions, 3 deletions

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 7da1dfe..3ab69fb 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -565,6 +565,7 @@ static int __ftrace_set_clr_event(struct trace_array *tr, const char *match,
 static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
 {
 	char *event = NULL, *sub = NULL, *match;
+	int ret;
 
 	/*
 	 * The buf format can be <subsystem>:<event-name>
@@ -590,7 +591,13 @@ static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
 			event = NULL;
 	}
 
-	return __ftrace_set_clr_event(tr, match, sub, event, set);
+	ret = __ftrace_set_clr_event(tr, match, sub, event, set);
+
+	/* Put back the colon to allow this to be called again */
+	if (buf)
+		*(buf - 1) = ':';
+
+	return ret;
 }
 
 /**
@@ -1753,6 +1760,8 @@ static void update_event_printk(struct ftrace_event_call *call,
 				ptr++;
 				/* Check for alpha chars like ULL */
 			} while (isalnum(*ptr));
+			if (!*ptr)
+				break;
 			/*
 			 * A number must have some kind of delimiter after
 			 * it, and we can ignore that too.
@@ -1779,12 +1788,16 @@ static void update_event_printk(struct ftrace_event_call *call,
 			do {
 				ptr++;
 			} while (isalnum(*ptr) || *ptr == '_');
+			if (!*ptr)
+				break;
 			/*
 			 * If what comes after this variable is a '.' or
 			 * '->' then we can continue to ignore that string.
 			 */
 			if (*ptr == '.' || (ptr[0] == '-' && ptr[1] == '>')) {
 				ptr += *ptr == '.' ? 1 : 2;
+				if (!*ptr)
+					break;
 				goto skip_more;
 			}
 			/*
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 9cfea4c..a51e796 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -1308,15 +1308,19 @@ void graph_trace_open(struct trace_iterator *iter)
 {
 	/* pid and depth on the last trace processed */
 	struct fgraph_data *data;
+	gfp_t gfpflags;
 	int cpu;
 
 	iter->private = NULL;
 
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	/* We can be called in atomic context via ftrace_dump() */
+	gfpflags = (in_atomic() || irqs_disabled()) ? GFP_ATOMIC : GFP_KERNEL;
+
+	data = kzalloc(sizeof(*data), gfpflags);
 	if (!data)
 		goto out_err;
 
-	data->cpu_data = alloc_percpu(struct fgraph_cpu_data);
+	data->cpu_data = alloc_percpu_gfp(struct fgraph_cpu_data, gfpflags);
 	if (!data->cpu_data)
 		goto out_err_free;