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, 78 insertions, 0 deletions

diff --git a/net/bluetooth/msft.h b/net/bluetooth/msft.h
new file mode 100644
index 000000000..fe538e9c9
--- /dev/null
+++ b/net/bluetooth/msft.h
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 Google Corporation
+ */
+
+#define MSFT_FEATURE_MASK_BREDR_RSSI_MONITOR		BIT(0)
+#define MSFT_FEATURE_MASK_LE_CONN_RSSI_MONITOR		BIT(1)
+#define MSFT_FEATURE_MASK_LE_ADV_RSSI_MONITOR		BIT(2)
+#define MSFT_FEATURE_MASK_LE_ADV_MONITOR		BIT(3)
+#define MSFT_FEATURE_MASK_CURVE_VALIDITY		BIT(4)
+#define MSFT_FEATURE_MASK_CONCURRENT_ADV_MONITOR	BIT(5)
+
+#if IS_ENABLED(CONFIG_BT_MSFTEXT)
+
+bool msft_monitor_supported(struct hci_dev *hdev);
+void msft_register(struct hci_dev *hdev);
+void msft_release(struct hci_dev *hdev);
+void msft_do_open(struct hci_dev *hdev);
+void msft_do_close(struct hci_dev *hdev);
+void msft_vendor_evt(struct hci_dev *hdev, void *data, struct sk_buff *skb);
+__u64 msft_get_features(struct hci_dev *hdev);
+int msft_add_monitor_pattern(struct hci_dev *hdev, struct adv_monitor *monitor);
+int msft_remove_monitor(struct hci_dev *hdev, struct adv_monitor *monitor);
+void msft_req_add_set_filter_enable(struct hci_request *req, bool enable);
+int msft_set_filter_enable(struct hci_dev *hdev, bool enable);
+int msft_suspend_sync(struct hci_dev *hdev);
+int msft_resume_sync(struct hci_dev *hdev);
+bool msft_curve_validity(struct hci_dev *hdev);
+
+#else
+
+static inline bool msft_monitor_supported(struct hci_dev *hdev)
+{
+	return false;
+}
+
+static inline void msft_register(struct hci_dev *hdev) {}
+static inline void msft_release(struct hci_dev *hdev) {}
+static inline void msft_do_open(struct hci_dev *hdev) {}
+static inline void msft_do_close(struct hci_dev *hdev) {}
+static inline void msft_vendor_evt(struct hci_dev *hdev, void *data,
+				   struct sk_buff *skb) {}
+static inline __u64 msft_get_features(struct hci_dev *hdev) { return 0; }
+static inline int msft_add_monitor_pattern(struct hci_dev *hdev,
+					   struct adv_monitor *monitor)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int msft_remove_monitor(struct hci_dev *hdev,
+				      struct adv_monitor *monitor)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline void msft_req_add_set_filter_enable(struct hci_request *req,
+						  bool enable) {}
+static inline int msft_set_filter_enable(struct hci_dev *hdev, bool enable)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int msft_suspend_sync(struct hci_dev *hdev)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int msft_resume_sync(struct hci_dev *hdev)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline bool msft_curve_validity(struct hci_dev *hdev)
+{
+	return false;
+}
+
+#endif