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, 84 insertions, 0 deletions

diff --git a/include/net/gen_stats.h b/include/net/gen_stats.h
new file mode 100644
index 000000000..856b5e90f
--- /dev/null
+++ b/include/net/gen_stats.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NET_GEN_STATS_H
+#define __NET_GEN_STATS_H
+
+#include <linux/gen_stats.h>
+#include <linux/socket.h>
+#include <linux/rtnetlink.h>
+#include <linux/pkt_sched.h>
+
+/* Throughput stats.
+ * Must be initialized beforehand with gnet_stats_basic_sync_init().
+ *
+ * If no reads can ever occur parallel to writes (e.g. stack-allocated
+ * bstats), then the internal stat values can be written to and read
+ * from directly. Otherwise, use _bstats_set/update() for writes and
+ * gnet_stats_add_basic() for reads.
+ */
+struct gnet_stats_basic_sync {
+	u64_stats_t bytes;
+	u64_stats_t packets;
+	struct u64_stats_sync syncp;
+} __aligned(2 * sizeof(u64));
+
+struct net_rate_estimator;
+
+struct gnet_dump {
+	spinlock_t *      lock;
+	struct sk_buff *  skb;
+	struct nlattr *   tail;
+
+	/* Backward compatibility */
+	int               compat_tc_stats;
+	int               compat_xstats;
+	int               padattr;
+	void *            xstats;
+	int               xstats_len;
+	struct tc_stats   tc_stats;
+};
+
+void gnet_stats_basic_sync_init(struct gnet_stats_basic_sync *b);
+int gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock,
+			  struct gnet_dump *d, int padattr);
+
+int gnet_stats_start_copy_compat(struct sk_buff *skb, int type,
+				 int tc_stats_type, int xstats_type,
+				 spinlock_t *lock, struct gnet_dump *d,
+				 int padattr);
+
+int gnet_stats_copy_basic(struct gnet_dump *d,
+			  const struct gnet_stats_basic_sync __percpu *cpu,
+			  const struct gnet_stats_basic_sync *b, bool running);
+void gnet_stats_add_basic(struct gnet_stats_basic_sync *bstats,
+			  const struct gnet_stats_basic_sync __percpu *cpu,
+			  const struct gnet_stats_basic_sync *b, bool running);
+int gnet_stats_copy_basic_hw(struct gnet_dump *d,
+			     const struct gnet_stats_basic_sync __percpu *cpu,
+			     const struct gnet_stats_basic_sync *b, bool running);
+int gnet_stats_copy_rate_est(struct gnet_dump *d,
+			     struct net_rate_estimator __rcu **ptr);
+int gnet_stats_copy_queue(struct gnet_dump *d,
+			  const struct gnet_stats_queue __percpu *cpu_q,
+			  const struct gnet_stats_queue *q, __u32 qlen);
+void gnet_stats_add_queue(struct gnet_stats_queue *qstats,
+			  const struct gnet_stats_queue __percpu *cpu_q,
+			  const struct gnet_stats_queue *q);
+int gnet_stats_copy_app(struct gnet_dump *d, void *st, int len);
+
+int gnet_stats_finish_copy(struct gnet_dump *d);
+
+int gen_new_estimator(struct gnet_stats_basic_sync *bstats,
+		      struct gnet_stats_basic_sync __percpu *cpu_bstats,
+		      struct net_rate_estimator __rcu **rate_est,
+		      spinlock_t *lock,
+		      bool running, struct nlattr *opt);
+void gen_kill_estimator(struct net_rate_estimator __rcu **ptr);
+int gen_replace_estimator(struct gnet_stats_basic_sync *bstats,
+			  struct gnet_stats_basic_sync __percpu *cpu_bstats,
+			  struct net_rate_estimator __rcu **ptr,
+			  spinlock_t *lock,
+			  bool running, struct nlattr *opt);
+bool gen_estimator_active(struct net_rate_estimator __rcu **ptr);
+bool gen_estimator_read(struct net_rate_estimator __rcu **ptr,
+			struct gnet_stats_rate_est64 *sample);
+#endif