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, 125 insertions, 0 deletions

diff --git a/include/drm/drm_module.h b/include/drm/drm_module.h
new file mode 100644
index 000000000..4db1ae03d
--- /dev/null
+++ b/include/drm/drm_module.h
@@ -0,0 +1,125 @@
+/* SPDX-License-Identifier: MIT */
+
+#ifndef DRM_MODULE_H
+#define DRM_MODULE_H
+
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+
+#include <drm/drm_drv.h>
+
+/**
+ * DOC: overview
+ *
+ * This library provides helpers registering DRM drivers during module
+ * initialization and shutdown. The provided helpers act like bus-specific
+ * module helpers, such as module_pci_driver(), but respect additional
+ * parameters that control DRM driver registration.
+ *
+ * Below is an example of initializing a DRM driver for a device on the
+ * PCI bus.
+ *
+ * .. code-block:: c
+ *
+ *	struct pci_driver my_pci_drv = {
+ *	};
+ *
+ *	drm_module_pci_driver(my_pci_drv);
+ *
+ * The generated code will test if DRM drivers are enabled and register
+ * the PCI driver my_pci_drv. For more complex module initialization, you
+ * can still use module_init() and module_exit() in your driver.
+ */
+
+/*
+ * PCI drivers
+ */
+
+static inline int __init drm_pci_register_driver(struct pci_driver *pci_drv)
+{
+	if (drm_firmware_drivers_only())
+		return -ENODEV;
+
+	return pci_register_driver(pci_drv);
+}
+
+/**
+ * drm_module_pci_driver - Register a DRM driver for PCI-based devices
+ * @__pci_drv: the PCI driver structure
+ *
+ * Registers a DRM driver for devices on the PCI bus. The helper
+ * macro behaves like module_pci_driver() but tests the state of
+ * drm_firmware_drivers_only(). For more complex module initialization,
+ * use module_init() and module_exit() directly.
+ *
+ * Each module may only use this macro once. Calling it replaces
+ * module_init() and module_exit().
+ */
+#define drm_module_pci_driver(__pci_drv) \
+	module_driver(__pci_drv, drm_pci_register_driver, pci_unregister_driver)
+
+static inline int __init
+drm_pci_register_driver_if_modeset(struct pci_driver *pci_drv, int modeset)
+{
+	if (drm_firmware_drivers_only() && modeset == -1)
+		return -ENODEV;
+	if (modeset == 0)
+		return -ENODEV;
+
+	return pci_register_driver(pci_drv);
+}
+
+static inline void __exit
+drm_pci_unregister_driver_if_modeset(struct pci_driver *pci_drv, int modeset)
+{
+	pci_unregister_driver(pci_drv);
+}
+
+/**
+ * drm_module_pci_driver_if_modeset - Register a DRM driver for PCI-based devices
+ * @__pci_drv: the PCI driver structure
+ * @__modeset: an additional parameter that disables the driver
+ *
+ * This macro is deprecated and only provided for existing drivers. For
+ * new drivers, use drm_module_pci_driver().
+ *
+ * Registers a DRM driver for devices on the PCI bus. The helper macro
+ * behaves like drm_module_pci_driver() with an additional driver-specific
+ * flag. If __modeset is 0, the driver has been disabled, if __modeset is
+ * -1 the driver state depends on the global DRM state. For all other
+ * values, the PCI driver has been enabled. The default should be -1.
+ */
+#define drm_module_pci_driver_if_modeset(__pci_drv, __modeset) \
+	module_driver(__pci_drv, drm_pci_register_driver_if_modeset, \
+		      drm_pci_unregister_driver_if_modeset, __modeset)
+
+/*
+ * Platform drivers
+ */
+
+static inline int __init
+drm_platform_driver_register(struct platform_driver *platform_drv)
+{
+	if (drm_firmware_drivers_only())
+		return -ENODEV;
+
+	return platform_driver_register(platform_drv);
+}
+
+/**
+ * drm_module_platform_driver - Register a DRM driver for platform devices
+ * @__platform_drv: the platform driver structure
+ *
+ * Registers a DRM driver for devices on the platform bus. The helper
+ * macro behaves like module_platform_driver() but tests the state of
+ * drm_firmware_drivers_only(). For more complex module initialization,
+ * use module_init() and module_exit() directly.
+ *
+ * Each module may only use this macro once. Calling it replaces
+ * module_init() and module_exit().
+ */
+#define drm_module_platform_driver(__platform_drv) \
+	module_driver(__platform_drv, drm_platform_driver_register, \
+		      platform_driver_unregister)
+
+#endif