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, 62 insertions, 0 deletions

diff --git a/net/rxrpc/misc.c b/net/rxrpc/misc.c
new file mode 100644
index 000000000..8fcc8139d
--- /dev/null
+++ b/net/rxrpc/misc.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Miscellaneous bits
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <linux/kernel.h>
+#include <net/sock.h>
+#include <net/af_rxrpc.h>
+#include "ar-internal.h"
+
+/*
+ * The maximum listening backlog queue size that may be set on a socket by
+ * listen().
+ */
+unsigned int rxrpc_max_backlog __read_mostly = 10;
+
+/*
+ * How long to wait before scheduling an ACK with subtype DELAY (in ms).
+ *
+ * We use this when we've received new data packets.  If those packets aren't
+ * all consumed within this time we will send a DELAY ACK if an ACK was not
+ * requested to let the sender know it doesn't need to resend.
+ */
+unsigned long rxrpc_soft_ack_delay = 1000;
+
+/*
+ * How long to wait before scheduling an ACK with subtype IDLE (in ms).
+ *
+ * We use this when we've consumed some previously soft-ACK'd packets when
+ * further packets aren't immediately received to decide when to send an IDLE
+ * ACK let the other end know that it can free up its Tx buffer space.
+ */
+unsigned long rxrpc_idle_ack_delay = 500;
+
+/*
+ * Receive window size in packets.  This indicates the maximum number of
+ * unconsumed received packets we're willing to retain in memory.  Once this
+ * limit is hit, we should generate an EXCEEDS_WINDOW ACK and discard further
+ * packets.
+ */
+unsigned int rxrpc_rx_window_size = 255;
+
+/*
+ * Maximum Rx MTU size.  This indicates to the sender the size of jumbo packet
+ * made by gluing normal packets together that we're willing to handle.
+ */
+unsigned int rxrpc_rx_mtu = RXRPC_JUMBO(46);
+
+/*
+ * The maximum number of fragments in a received jumbo packet that we tell the
+ * sender that we're willing to handle.
+ */
+unsigned int rxrpc_rx_jumbo_max = 46;
+
+#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
+/*
+ * The delay to inject into packet reception.
+ */
+unsigned long rxrpc_inject_rx_delay;
+#endif