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>

2 files changed, 73 insertions, 0 deletions

diff --git a/drivers/soc/gemini/Makefile b/drivers/soc/gemini/Makefile
new file mode 100644
index 000000000..8cbd1e45d
--- /dev/null
+++ b/drivers/soc/gemini/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-y	+= soc-gemini.o
diff --git a/drivers/soc/gemini/soc-gemini.c b/drivers/soc/gemini/soc-gemini.c
new file mode 100644
index 000000000..642b96c91
--- /dev/null
+++ b/drivers/soc/gemini/soc-gemini.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017 Linaro Ltd.
+ *
+ * Author: Linus Walleij <linus.walleij@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/of.h>
+
+#define GLOBAL_WORD_ID				0x00
+#define GEMINI_GLOBAL_ARB1_CTRL			0x2c
+#define GEMINI_ARB1_BURST_MASK			GENMASK(21, 16)
+#define GEMINI_ARB1_BURST_SHIFT			16
+/* These all define the priority on the BUS2 backplane */
+#define GEMINI_ARB1_PRIO_MASK			GENMASK(9, 0)
+#define GEMINI_ARB1_DMAC_HIGH_PRIO		BIT(0)
+#define GEMINI_ARB1_IDE_HIGH_PRIO		BIT(1)
+#define GEMINI_ARB1_RAID_HIGH_PRIO		BIT(2)
+#define GEMINI_ARB1_SECURITY_HIGH_PRIO		BIT(3)
+#define GEMINI_ARB1_GMAC0_HIGH_PRIO		BIT(4)
+#define GEMINI_ARB1_GMAC1_HIGH_PRIO		BIT(5)
+#define GEMINI_ARB1_USB0_HIGH_PRIO		BIT(6)
+#define GEMINI_ARB1_USB1_HIGH_PRIO		BIT(7)
+#define GEMINI_ARB1_PCI_HIGH_PRIO		BIT(8)
+#define GEMINI_ARB1_TVE_HIGH_PRIO		BIT(9)
+
+#define GEMINI_DEFAULT_BURST_SIZE		0x20
+#define GEMINI_DEFAULT_PRIO			(GEMINI_ARB1_GMAC0_HIGH_PRIO | \
+						 GEMINI_ARB1_GMAC1_HIGH_PRIO)
+
+static int __init gemini_soc_init(void)
+{
+	struct regmap *map;
+	u32 rev;
+	u32 val;
+	int ret;
+
+	/* Multiplatform guard, only proceed on Gemini */
+	if (!of_machine_is_compatible("cortina,gemini"))
+		return 0;
+
+	map = syscon_regmap_lookup_by_compatible("cortina,gemini-syscon");
+	if (IS_ERR(map))
+		return PTR_ERR(map);
+	ret = regmap_read(map, GLOBAL_WORD_ID, &rev);
+	if (ret)
+		return ret;
+
+	val = (GEMINI_DEFAULT_BURST_SIZE << GEMINI_ARB1_BURST_SHIFT) |
+		GEMINI_DEFAULT_PRIO;
+
+	/* Set up system arbitration */
+	regmap_update_bits(map,
+			   GEMINI_GLOBAL_ARB1_CTRL,
+			   GEMINI_ARB1_BURST_MASK | GEMINI_ARB1_PRIO_MASK,
+			   val);
+
+	pr_info("Gemini SoC %04x revision %02x, set arbitration %08x\n",
+		rev >> 8, rev & 0xff, val);
+
+	return 0;
+}
+subsys_initcall(gemini_soc_init);