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, 20 insertions, 0 deletions

diff --git a/include/sound/max9768.h b/include/sound/max9768.h
new file mode 100644
index 000000000..8509ba007
--- /dev/null
+++ b/include/sound/max9768.h
@@ -0,0 +1,20 @@
+/*
+ * Platform data for MAX9768
+ * Copyright (C) 2011, 2012 by Wolfram Sang, Pengutronix e.K.
+ * same licence as the driver
+ */
+
+#ifndef __SOUND_MAX9768_PDATA_H__
+#define __SOUND_MAX9768_PDATA_H__
+
+/**
+ * struct max9768_pdata - optional platform specific MAX9768 configuration
+ * @flags: configuration flags, e.g. set classic PWM mode (check datasheet
+ *         regarding "filterless modulation" which is default).
+ */
+struct max9768_pdata {
+	unsigned flags;
+#define MAX9768_FLAG_CLASSIC_PWM	(1 << 0)
+};
+
+#endif /* __SOUND_MAX9768_PDATA_H__*/