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, 55 insertions, 0 deletions

diff --git a/drivers/usb/image/microtek.h b/drivers/usb/image/microtek.h
new file mode 100644
index 000000000..7bd5f4639
--- /dev/null
+++ b/drivers/usb/image/microtek.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+ /*
+ * Driver for Microtek Scanmaker X6 USB scanner and possibly others.
+ * 
+ * (C) Copyright 2000 John Fremlin <vii@penguinpowered.com>
+ * (C) Copyright 2000 Oliver Neukum <Oliver.Neukum@lrz.uni-muenchen.de>
+ *
+ * See microtek.c for history
+ *
+ */
+
+typedef void (*mts_scsi_cmnd_callback)(struct scsi_cmnd *);
+
+
+struct mts_transfer_context
+{
+	struct mts_desc *instance;
+	mts_scsi_cmnd_callback final_callback;
+	struct scsi_cmnd *srb;
+	
+	void *data;
+	unsigned data_length;
+	int data_pipe;
+	struct scatterlist *curr_sg;
+
+	u8 *scsi_status; /* status returned from ep_response after command completion */
+};
+
+
+struct mts_desc {
+	struct mts_desc *next;
+	struct mts_desc *prev;
+
+	struct usb_device *usb_dev;
+	struct usb_interface *usb_intf;
+
+	/* Endpoint addresses */
+	u8 ep_out;
+	u8 ep_response;
+	u8 ep_image;
+
+	struct Scsi_Host *host;
+
+	struct urb *urb;
+	struct mts_transfer_context context;
+};
+
+
+#define MTS_EP_OUT	0x1
+#define MTS_EP_RESPONSE	0x2
+#define MTS_EP_IMAGE	0x3
+#define MTS_EP_TOTAL	0x3
+
+#define MTS_SCSI_ERR_MASK ~0x3fu
+