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, 31 insertions, 0 deletions

diff --git a/tools/perf/util/evswitch.h b/tools/perf/util/evswitch.h
new file mode 100644
index 000000000..8ffdbe526
--- /dev/null
+++ b/tools/perf/util/evswitch.h
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2019, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
+#ifndef __PERF_EVSWITCH_H
+#define __PERF_EVSWITCH_H 1
+
+#include <stdbool.h>
+#include <stdio.h>
+
+struct evsel;
+struct evlist;
+
+struct evswitch {
+	struct evsel *on, *off;
+	const char   *on_name, *off_name;
+	bool	     discarding;
+	bool	     show_on_off_events;
+};
+
+int evswitch__init(struct evswitch *evswitch, struct evlist *evlist, FILE *fp);
+
+bool evswitch__discard(struct evswitch *evswitch, struct evsel *evsel);
+
+#define OPTS_EVSWITCH(evswitch)								  \
+	OPT_STRING(0, "switch-on", &(evswitch)->on_name,				  \
+		   "event", "Consider events after the occurrence of this event"),	  \
+	OPT_STRING(0, "switch-off", &(evswitch)->off_name,				  \
+		   "event", "Stop considering events after the occurrence of this event"), \
+	OPT_BOOLEAN(0, "show-on-off-events", &(evswitch)->show_on_off_events,		  \
+		    "Show the on/off switch events, used with --switch-on and --switch-off")
+
+#endif /* __PERF_EVSWITCH_H */