staging: rtl8723bs: fix OOB read in rtw_action_frame_parse()grafted

rtw_action_frame_parse() takes a frame_len parameter but never
actually checks it before indexing into the frame body:

	const u8 *frame_body = frame + sizeof(struct ieee80211_hdr_3addr);
	...
	c = frame_body[0];
	...
	a = frame_body[1];

frame_body already points 24 bytes (sizeof(struct
ieee80211_hdr_3addr)) into frame, so reading frame_body[0] and
frame_body[1] requires frame_len >= 26. A management action frame
shorter than that (e.g. exactly 24 bytes, the minimum a malicious
peer can send) causes a 1-2 byte out-of-bounds read.

This is reachable from rtw_cfg80211_monitor_if_xmit_entry() and
cfg80211_rtw_mgmt_tx() in ioctl_cfg80211.c, both of which pass
attacker/user-influenced frame buffers and lengths straight through.

Add the missing length check before frame_body is dereferenced.

Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver")
Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 114 insertions, 0 deletions

diff --git a/drivers/input/misc/gpio-beeper.c b/drivers/input/misc/gpio-beeper.c
new file mode 100644
index 000000000..3d65cb4f4
--- /dev/null
+++ b/drivers/input/misc/gpio-beeper.c
@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Generic GPIO beeper driver
+ *
+ * Copyright (C) 2013-2014 Alexander Shiyan <shc_work@mail.ru>
+ */
+
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
+#include <linux/workqueue.h>
+#include <linux/platform_device.h>
+
+#define BEEPER_MODNAME		"gpio-beeper"
+
+struct gpio_beeper {
+	struct work_struct	work;
+	struct gpio_desc	*desc;
+	bool			beeping;
+};
+
+static void gpio_beeper_toggle(struct gpio_beeper *beep, bool on)
+{
+	gpiod_set_value_cansleep(beep->desc, on);
+}
+
+static void gpio_beeper_work(struct work_struct *work)
+{
+	struct gpio_beeper *beep = container_of(work, struct gpio_beeper, work);
+
+	gpio_beeper_toggle(beep, beep->beeping);
+}
+
+static int gpio_beeper_event(struct input_dev *dev, unsigned int type,
+			     unsigned int code, int value)
+{
+	struct gpio_beeper *beep = input_get_drvdata(dev);
+
+	if (type != EV_SND || code != SND_BELL)
+		return -ENOTSUPP;
+
+	if (value < 0)
+		return -EINVAL;
+
+	beep->beeping = value;
+	/* Schedule work to actually turn the beeper on or off */
+	schedule_work(&beep->work);
+
+	return 0;
+}
+
+static void gpio_beeper_close(struct input_dev *input)
+{
+	struct gpio_beeper *beep = input_get_drvdata(input);
+
+	cancel_work_sync(&beep->work);
+	gpio_beeper_toggle(beep, false);
+}
+
+static int gpio_beeper_probe(struct platform_device *pdev)
+{
+	struct gpio_beeper *beep;
+	struct input_dev *input;
+
+	beep = devm_kzalloc(&pdev->dev, sizeof(*beep), GFP_KERNEL);
+	if (!beep)
+		return -ENOMEM;
+
+	beep->desc = devm_gpiod_get(&pdev->dev, NULL, GPIOD_OUT_LOW);
+	if (IS_ERR(beep->desc))
+		return PTR_ERR(beep->desc);
+
+	input = devm_input_allocate_device(&pdev->dev);
+	if (!input)
+		return -ENOMEM;
+
+	INIT_WORK(&beep->work, gpio_beeper_work);
+
+	input->name		= pdev->name;
+	input->id.bustype	= BUS_HOST;
+	input->id.vendor	= 0x0001;
+	input->id.product	= 0x0001;
+	input->id.version	= 0x0100;
+	input->close		= gpio_beeper_close;
+	input->event		= gpio_beeper_event;
+
+	input_set_capability(input, EV_SND, SND_BELL);
+
+	input_set_drvdata(input, beep);
+
+	return input_register_device(input);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id gpio_beeper_of_match[] = {
+	{ .compatible = "gpio-beeper", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, gpio_beeper_of_match);
+#endif
+
+static struct platform_driver gpio_beeper_platform_driver = {
+	.driver	= {
+		.name		= BEEPER_MODNAME,
+		.of_match_table	= of_match_ptr(gpio_beeper_of_match),
+	},
+	.probe	= gpio_beeper_probe,
+};
+module_platform_driver(gpio_beeper_platform_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
+MODULE_DESCRIPTION("Generic GPIO beeper driver");