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, 29 insertions, 0 deletions

diff --git a/include/trace/events/netlink.h b/include/trace/events/netlink.h
new file mode 100644
index 000000000..f036b8a20
--- /dev/null
+++ b/include/trace/events/netlink.h
@@ -0,0 +1,29 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM netlink
+
+#if !defined(_TRACE_NETLINK_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_NETLINK_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(netlink_extack,
+
+	TP_PROTO(const char *msg),
+
+	TP_ARGS(msg),
+
+	TP_STRUCT__entry(
+		__string(	msg,	msg	)
+	),
+
+	TP_fast_assign(
+		__assign_str(msg);
+	),
+
+	TP_printk("msg=%s", __get_str(msg))
+);
+
+#endif /* _TRACE_NETLINK_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>