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, 87 insertions, 0 deletions

diff --git a/drivers/acpi/tiny-power-button.c b/drivers/acpi/tiny-power-button.c
new file mode 100644
index 000000000..92516ef84
--- /dev/null
+++ b/drivers/acpi/tiny-power-button.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/acpi.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sched/signal.h>
+#include <acpi/button.h>
+
+MODULE_AUTHOR("Josh Triplett");
+MODULE_DESCRIPTION("ACPI Tiny Power Button Driver");
+MODULE_LICENSE("GPL");
+
+static int power_signal __read_mostly = CONFIG_ACPI_TINY_POWER_BUTTON_SIGNAL;
+module_param(power_signal, int, 0644);
+MODULE_PARM_DESC(power_signal, "Power button sends this signal to init");
+
+static const struct acpi_device_id tiny_power_button_device_ids[] = {
+	{ ACPI_BUTTON_HID_POWER, 0 },
+	{ ACPI_BUTTON_HID_POWERF, 0 },
+	{ "", 0 },
+};
+MODULE_DEVICE_TABLE(acpi, tiny_power_button_device_ids);
+
+static void acpi_tiny_power_button_notify(acpi_handle handle, u32 event, void *data)
+{
+	kill_cad_pid(power_signal, 1);
+}
+
+static void acpi_tiny_power_button_notify_run(void *not_used)
+{
+	acpi_tiny_power_button_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, NULL);
+}
+
+static u32 acpi_tiny_power_button_event(void *not_used)
+{
+	acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_tiny_power_button_notify_run, NULL);
+	return ACPI_INTERRUPT_HANDLED;
+}
+
+static int acpi_tiny_power_button_probe(struct platform_device *pdev)
+{
+	struct acpi_device *device;
+	acpi_status status;
+
+	device = ACPI_COMPANION(&pdev->dev);
+	if (!device)
+		return -ENODEV;
+
+	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) {
+		status = acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+							  acpi_tiny_power_button_event,
+							  NULL);
+	} else {
+		status = acpi_install_notify_handler(device->handle,
+						     ACPI_DEVICE_NOTIFY,
+						     acpi_tiny_power_button_notify,
+						     NULL);
+	}
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	return 0;
+}
+
+static void acpi_tiny_power_button_remove(struct platform_device *pdev)
+{
+	struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
+
+	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) {
+		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+						acpi_tiny_power_button_event);
+	} else {
+		acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+					   acpi_tiny_power_button_notify);
+	}
+	acpi_os_wait_events_complete();
+}
+
+static struct platform_driver acpi_tiny_power_button_driver = {
+	.probe = acpi_tiny_power_button_probe,
+	.remove = acpi_tiny_power_button_remove,
+	.driver = {
+		.name = "acpi-tiny-power-button",
+		.acpi_match_table = tiny_power_button_device_ids,
+	},
+};
+
+module_platform_driver(acpi_tiny_power_button_driver);