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, 117 insertions, 0 deletions

diff --git a/drivers/hid/hid-hyperx.c b/drivers/hid/hid-hyperx.c
new file mode 100644
index 000000000..18d2dc24c
--- /dev/null
+++ b/drivers/hid/hid-hyperx.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  HID driver for the HyperX QuadCast 2 microphone
+ *
+ *  The tap-to-mute button is handled entirely in the device firmware: it gates
+ *  the audio internally and does not send the Telephony "Phone Mute" usage its
+ *  own report descriptor advertises.  The resulting mute state is only reported
+ *  through a vendor-defined collection, which hid-input cannot map, so the
+ *  button is invisible to userspace.
+ *
+ *  Copyright (c) 2026 Benjamin Blume <benjaminblume@posteo.de>
+ */
+
+#include <linux/hid.h>
+#include <linux/input.h>
+#include <linux/module.h>
+
+#include "hid-ids.h"
+
+#define HYPERX_QC2_REPORT_ID	0x77
+#define HYPERX_QC2_EVENT_MUTE	0x06
+#define HYPERX_QC2_MUTE_LEN	3
+
+struct hyperx_drvdata {
+	struct input_dev *input;
+	bool muted;
+	bool have_state;
+};
+
+static int hyperx_input_configured(struct hid_device *hdev,
+				   struct hid_input *hi)
+{
+	struct hyperx_drvdata *drvdata = hid_get_drvdata(hdev);
+
+	/*
+	 * The device exposes several application collections.  Prefer the
+	 * telephony one, which already advertises KEY_MICMUTE, and fall back
+	 * to the first collection otherwise.
+	 */
+	if (!drvdata->input || test_bit(KEY_MICMUTE, hi->input->keybit)) {
+		drvdata->input = hi->input;
+		input_set_capability(drvdata->input, EV_KEY, KEY_MICMUTE);
+	}
+
+	return 0;
+}
+
+static int hyperx_raw_event(struct hid_device *hdev, struct hid_report *report,
+			    u8 *data, int size)
+{
+	struct hyperx_drvdata *drvdata = hid_get_drvdata(hdev);
+	bool muted;
+
+	if (!(hdev->claimed & HID_CLAIMED_INPUT) || !drvdata->input)
+		return 0;
+
+	if (size < HYPERX_QC2_MUTE_LEN || data[0] != HYPERX_QC2_REPORT_ID ||
+	    data[1] != HYPERX_QC2_EVENT_MUTE)
+		return 0;
+
+	muted = data[2];
+	if (drvdata->have_state && muted == drvdata->muted)
+		return 0;
+
+	drvdata->muted = muted;
+	drvdata->have_state = true;
+
+	/*
+	 * The device reports the resulting absolute state, while KEY_MICMUTE is
+	 * a momentary key that userspace acts on as a toggle.  Emit one
+	 * keypress per state change.
+	 */
+	input_report_key(drvdata->input, KEY_MICMUTE, 1);
+	input_sync(drvdata->input);
+	input_report_key(drvdata->input, KEY_MICMUTE, 0);
+	input_sync(drvdata->input);
+
+	return 0;
+}
+
+static int hyperx_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	struct hyperx_drvdata *drvdata;
+	int ret;
+
+	drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata)
+		return -ENOMEM;
+
+	hid_set_drvdata(hdev, drvdata);
+
+	ret = hid_parse(hdev);
+	if (ret)
+		return ret;
+
+	return hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+}
+
+static const struct hid_device_id hyperx_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_HP,
+			 USB_PRODUCT_ID_HP_HYPERX_QUADCAST_2) },
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, hyperx_devices);
+
+static struct hid_driver hyperx_driver = {
+	.name			= "hyperx",
+	.id_table		= hyperx_devices,
+	.probe			= hyperx_probe,
+	.input_configured	= hyperx_input_configured,
+	.raw_event		= hyperx_raw_event,
+};
+module_hid_driver(hyperx_driver);
+
+MODULE_DESCRIPTION("HID driver for the HyperX QuadCast 2 microphone");
+MODULE_AUTHOR("Benjamin Blume <benjaminblume@posteo.de>");
+MODULE_LICENSE("GPL");