Commit 4c6edb43 authored by Masami Hiramatsu (Google)'s avatar Masami Hiramatsu (Google)
Browse files

tracing: eprobe-event: Allocate string buffers from heap 

Allocate temporary string buffers for parsing eprobe-events
from heap instead of stack.

Link: https://lore.kernel.org/all/175323428599.57270.988038042425748956.stgit@devnote2/



Signed-off-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 33b4e38b

kernel/trace/trace_eprobe.c

+18 −4
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
 * Copyright (C) 2021, VMware Inc, Tzvetomir Stoyanov tz.stoyanov@gmail.com>

 *

 */

#include <linux/cleanup.h>

#include <linux/ftrace.h>

#include <linux/module.h>

#include <linux/mutex.h>
@@ -871,10 +872,10 @@ static int __trace_eprobe_create(int argc, const char *argv[]) 
	const char *event = NULL, *group = EPROBE_EVENT_SYSTEM;

	const char *sys_event = NULL, *sys_name = NULL;

	struct trace_event_call *event_call;

	char *buf1 __free(kfree) = NULL;

	char *buf2 __free(kfree) = NULL;

	char *gbuf __free(kfree) = NULL;

	struct trace_eprobe *ep = NULL;

	char buf1[MAX_EVENT_NAME_LEN];

	char buf2[MAX_EVENT_NAME_LEN];

	char gbuf[MAX_EVENT_NAME_LEN];

	int ret = 0, filter_idx = 0;

	int i, filter_cnt;
@@ -885,6 +886,9 @@ static int __trace_eprobe_create(int argc, const char *argv[]) 


	event = strchr(&argv[0][1], ':');

	if (event) {

		gbuf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL);

		if (!gbuf)

			goto mem_error;

		event++;

		ret = traceprobe_parse_event_name(&event, &group, gbuf,

						  event - argv[0]);
@@ -894,6 +898,11 @@ static int __trace_eprobe_create(int argc, const char *argv[]) 


	trace_probe_log_set_index(1);

	sys_event = argv[1];



	buf2 = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL);

	if (!buf2)

		goto mem_error;



	ret = traceprobe_parse_event_name(&sys_event, &sys_name, buf2, 0);

	if (ret || !sys_event || !sys_name) {

		trace_probe_log_err(0, NO_EVENT_INFO);
@@ -901,7 +910,9 @@ static int __trace_eprobe_create(int argc, const char *argv[]) 
	}



	if (!event) {

		strscpy(buf1, sys_event, MAX_EVENT_NAME_LEN);

		buf1 = kstrdup(sys_event, GFP_KERNEL);

		if (!buf1)

			goto mem_error;

		event = buf1;

	}
@@ -974,6 +985,9 @@ static int __trace_eprobe_create(int argc, const char *argv[]) 
	trace_probe_log_clear();

	return ret;



mem_error:

	ret = -ENOMEM;

	goto error;

parse_error:

	ret = -EINVAL;

error: