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, 212 insertions, 0 deletions

diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
new file mode 100644
index 000000000..6e70b320b
--- /dev/null
+++ b/include/net/xdp_sock.h
@@ -0,0 +1,212 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* AF_XDP internal functions
+ * Copyright(c) 2018 Intel Corporation.
+ */
+
+#ifndef _LINUX_XDP_SOCK_H
+#define _LINUX_XDP_SOCK_H
+
+#include <linux/bpf.h>
+#include <linux/workqueue.h>
+#include <linux/if_xdp.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <net/sock.h>
+
+#define XDP_UMEM_SG_FLAG BIT(3)
+
+struct net_device;
+struct xsk_queue;
+struct xdp_buff;
+
+struct xdp_umem {
+	void *addrs;
+	u64 size;
+	u32 headroom;
+	u32 chunk_size;
+	u32 chunks;
+	u32 npgs;
+	struct user_struct *user;
+	refcount_t users;
+	u8 flags;
+	u8 tx_metadata_len;
+	bool zc;
+	struct page **pgs;
+	int id;
+	struct list_head xsk_dma_list;
+	struct work_struct work;
+};
+
+struct xsk_map {
+	struct bpf_map map;
+	spinlock_t lock; /* Synchronize map updates */
+	atomic_t count;
+	struct xdp_sock __rcu *xsk_map[];
+};
+
+struct xdp_sock {
+	/* struct sock must be the first member of struct xdp_sock */
+	struct sock sk;
+	struct xsk_queue *rx ____cacheline_aligned_in_smp;
+	struct net_device *dev;
+	struct xdp_umem *umem;
+	struct list_head flush_node;
+	struct xsk_buff_pool *pool;
+	u16 queue_id;
+	bool zc;
+	bool sg;
+	enum {
+		XSK_READY = 0,
+		XSK_BOUND,
+		XSK_UNBOUND,
+	} state;
+
+	struct xsk_queue *tx ____cacheline_aligned_in_smp;
+	struct list_head tx_list;
+	/* record the number of tx descriptors sent by this xsk and
+	 * when it exceeds MAX_PER_SOCKET_BUDGET, an opportunity needs
+	 * to be given to other xsks for sending tx descriptors, thereby
+	 * preventing other XSKs from being starved.
+	 */
+	u32 tx_budget_spent;
+
+	/* Statistics */
+	u64 rx_dropped;
+	u64 rx_queue_full;
+
+	/* When __xsk_generic_xmit() must return before it sees the EOP descriptor for the current
+	 * packet, the partially built skb is saved here so that packet building can resume in next
+	 * call of __xsk_generic_xmit().
+	 */
+	struct sk_buff *skb;
+	bool drain_cont;
+
+	struct list_head map_list;
+	/* Protects map_list */
+	spinlock_t map_list_lock;
+	u32 max_tx_budget;
+	/* Protects multiple processes in the control path */
+	struct mutex mutex;
+	struct xsk_queue *fq_tmp; /* Only as tmp storage before bind */
+	struct xsk_queue *cq_tmp; /* Only as tmp storage before bind */
+};
+
+/*
+ * AF_XDP TX metadata hooks for network devices.
+ * The following hooks can be defined; unless noted otherwise, they are
+ * optional and can be filled with a null pointer.
+ *
+ * void (*tmo_request_timestamp)(void *priv)
+ *     Called when AF_XDP frame requested egress timestamp.
+ *
+ * u64 (*tmo_fill_timestamp)(void *priv)
+ *     Called when AF_XDP frame, that had requested egress timestamp,
+ *     received a completion. The hook needs to return the actual HW timestamp.
+ *
+ * void (*tmo_request_checksum)(u16 csum_start, u16 csum_offset, void *priv)
+ *     Called when AF_XDP frame requested HW checksum offload. csum_start
+ *     indicates position where checksumming should start.
+ *     csum_offset indicates position where checksum should be stored.
+ *
+ * void (*tmo_request_launch_time)(u64 launch_time, void *priv)
+ *     Called when AF_XDP frame requested launch time HW offload support.
+ *     launch_time indicates the PTP time at which the device can schedule the
+ *     packet for transmission.
+ */
+struct xsk_tx_metadata_ops {
+	void	(*tmo_request_timestamp)(void *priv);
+	u64	(*tmo_fill_timestamp)(void *priv);
+	void	(*tmo_request_checksum)(u16 csum_start, u16 csum_offset, void *priv);
+	void	(*tmo_request_launch_time)(u64 launch_time, void *priv);
+};
+
+#ifdef CONFIG_XDP_SOCKETS
+
+int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
+int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp);
+void __xsk_map_flush(struct list_head *flush_list);
+INDIRECT_CALLABLE_DECLARE(void xsk_destruct_skb(struct sk_buff *));
+
+/**
+ *  xsk_tx_metadata_to_compl - Save enough relevant metadata information
+ *  to perform tx completion in the future.
+ *  @meta: pointer to AF_XDP metadata area
+ *  @compl: pointer to output struct xsk_tx_metadata_to_compl
+ *
+ *  This function should be called by the networking device when
+ *  it prepares AF_XDP egress packet. The value of @compl should be stored
+ *  and passed to xsk_tx_metadata_complete upon TX completion.
+ */
+static inline void xsk_tx_metadata_to_compl(struct xsk_tx_metadata *meta,
+					    struct xsk_tx_metadata_compl *compl)
+{
+	compl->tx_timestamp = NULL;
+
+	if (!meta)
+		return;
+
+	/* we can only arrive here if the completion timestamp has been
+	 * requested via XDP_TXMD_FLAGS_TIMESTAMP, see xsk_tx_metadata_request
+	 */
+
+	compl->tx_timestamp = &meta->completion.tx_timestamp;
+}
+
+/**
+ *  xsk_tx_metadata_complete - Evaluate AF_XDP TX metadata at completion
+ *  and call appropriate xsk_tx_metadata_ops operation.
+ *  @compl: pointer to completion metadata produced from xsk_tx_metadata_to_compl
+ *  @ops: pointer to struct xsk_tx_metadata_ops
+ *  @priv: pointer to driver-private aread
+ *
+ *  This function should be called by the networking device upon
+ *  AF_XDP egress completion.
+ */
+static inline void xsk_tx_metadata_complete(struct xsk_tx_metadata_compl *compl,
+					    const struct xsk_tx_metadata_ops *ops,
+					    void *priv)
+{
+	if (!compl)
+		return;
+	if (!compl->tx_timestamp)
+		return;
+
+	*compl->tx_timestamp = ops->tmo_fill_timestamp(priv);
+}
+
+#else
+
+static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
+{
+	return -ENOTSUPP;
+}
+
+static inline int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline void __xsk_map_flush(struct list_head *flush_list)
+{
+}
+
+#ifdef CONFIG_MITIGATION_RETPOLINE
+static inline void xsk_destruct_skb(struct sk_buff *skb)
+{
+}
+#endif
+
+static inline void xsk_tx_metadata_to_compl(struct xsk_tx_metadata *meta,
+					    struct xsk_tx_metadata_compl *compl)
+{
+}
+
+static inline void xsk_tx_metadata_complete(struct xsk_tx_metadata_compl *compl,
+					    const struct xsk_tx_metadata_ops *ops,
+					    void *priv)
+{
+}
+
+#endif /* CONFIG_XDP_SOCKETS */
+#endif /* _LINUX_XDP_SOCK_H */