Commit 6f3cf440 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Ingo Molnar
Browse files

kprobe-tracer: Check new event/group name 



Check new event/group name is same syntax as a C symbol. In other
words, checking the name is as like as other tracepoint events.

This can prevent user to create an event with useless name (e.g.
foo|bar, foo*bar).

Signed-off-by: default avatarMasami Hiramatsu <mhiramat@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20091216222408.14459.68790.stgit@dhcp-100-2-132.bos.redhat.com>
[ v2: minor cleanups ]
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 96c96612

kernel/trace/trace_kprobe.c

+25 −6
Original line number Diff line number Diff line
@@ -282,6 +282,18 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); 
static int kretprobe_dispatcher(struct kretprobe_instance *ri,

				struct pt_regs *regs);



/* Check the name is good for event/group */

static int check_event_name(const char *name)

{

	if (!isalpha(*name) && *name != '_')

		return 0;

	while (*++name != '\0') {

		if (!isalpha(*name) && !isdigit(*name) && *name != '_')

			return 0;

	}

	return 1;

}



/*

 * Allocate new trace_probe and initialize it (including kprobes).

 */
@@ -293,10 +305,11 @@ static struct trace_probe *alloc_trace_probe(const char *group, 
					     int nargs, int is_return)

{

	struct trace_probe *tp;

	int ret = -ENOMEM;



	tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL);

	if (!tp)

		return ERR_PTR(-ENOMEM);

		return ERR_PTR(ret);



	if (symbol) {

		tp->symbol = kstrdup(symbol, GFP_KERNEL);
@@ -312,14 +325,20 @@ static struct trace_probe *alloc_trace_probe(const char *group, 
	else

		tp->rp.kp.pre_handler = kprobe_dispatcher;



	if (!event)

	if (!event || !check_event_name(event)) {

		ret = -EINVAL;

		goto error;

	}



	tp->call.name = kstrdup(event, GFP_KERNEL);

	if (!tp->call.name)

		goto error;



	if (!group)

	if (!group || !check_event_name(group)) {

		ret = -EINVAL;

		goto error;

	}



	tp->call.system = kstrdup(group, GFP_KERNEL);

	if (!tp->call.system)

		goto error;
@@ -330,7 +349,7 @@ error: 
	kfree(tp->call.name);

	kfree(tp->symbol);

	kfree(tp);

	return ERR_PTR(-ENOMEM);

	return ERR_PTR(ret);

}



static void free_probe_arg(struct probe_arg *arg)
@@ -695,10 +714,10 @@ static int create_trace_probe(int argc, char **argv) 
	if (!event) {

		/* Make a new event name */

		if (symbol)

			snprintf(buf, MAX_EVENT_NAME_LEN, "%c@%s%+ld",

			snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",

				 is_return ? 'r' : 'p', symbol, offset);

		else

			snprintf(buf, MAX_EVENT_NAME_LEN, "%c@0x%p",

			snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",

				 is_return ? 'r' : 'p', addr);

		event = buf;

	}

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