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, 41 insertions, 0 deletions

diff --git a/include/media/videobuf2-memops.h b/include/media/videobuf2-memops.h
new file mode 100644
index 000000000..4b5b84f93
--- /dev/null
+++ b/include/media/videobuf2-memops.h
@@ -0,0 +1,41 @@
+/*
+ * videobuf2-memops.h - generic memory handling routines for videobuf2
+ *
+ * Copyright (C) 2010 Samsung Electronics
+ *
+ * Author: Pawel Osciak <pawel@osciak.com>
+ *	   Marek Szyprowski <m.szyprowski@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation.
+ */
+
+#ifndef _MEDIA_VIDEOBUF2_MEMOPS_H
+#define _MEDIA_VIDEOBUF2_MEMOPS_H
+
+#include <media/videobuf2-v4l2.h>
+#include <linux/mm.h>
+#include <linux/refcount.h>
+
+/**
+ * struct vb2_vmarea_handler - common vma refcount tracking handler.
+ *
+ * @refcount:	pointer to &refcount_t entry in the buffer.
+ * @put:	callback to function that decreases buffer refcount.
+ * @arg:	argument for @put callback.
+ */
+struct vb2_vmarea_handler {
+	refcount_t		*refcount;
+	void			(*put)(void *arg);
+	void			*arg;
+};
+
+extern const struct vm_operations_struct vb2_common_vm_ops;
+
+struct frame_vector *vb2_create_framevec(unsigned long start,
+					 unsigned long length,
+					 bool write);
+void vb2_destroy_framevec(struct frame_vector *vec);
+
+#endif