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, 91 insertions, 0 deletions

diff --git a/drivers/mfd/act8945a.c b/drivers/mfd/act8945a.c
new file mode 100644
index 000000000..cafefb445
--- /dev/null
+++ b/drivers/mfd/act8945a.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MFD driver for Active-semi ACT8945a PMIC
+ *
+ * Copyright (C) 2015 Atmel Corporation.
+ *
+ * Author: Wenyou Yang <wenyou.yang@atmel.com>
+ */
+
+#include <linux/i2c.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+static const struct mfd_cell act8945a_devs[] = {
+	{
+		.name = "act8945a-regulator",
+	},
+	{
+		.name = "act8945a-charger",
+		.of_compatible = "active-semi,act8945a-charger",
+	},
+};
+
+static const struct regmap_config act8945a_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
+static int act8945a_i2c_probe(struct i2c_client *i2c)
+{
+	int ret;
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_i2c(i2c, &act8945a_regmap_config);
+	if (IS_ERR(regmap)) {
+		ret = PTR_ERR(regmap);
+		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
+		return ret;
+	}
+
+	i2c_set_clientdata(i2c, regmap);
+
+	ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_NONE,
+				   act8945a_devs, ARRAY_SIZE(act8945a_devs),
+				   NULL, 0, NULL);
+	if (ret) {
+		dev_err(&i2c->dev, "Failed to add sub devices\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct i2c_device_id act8945a_i2c_id[] = {
+	{ "act8945a" },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, act8945a_i2c_id);
+
+static const struct of_device_id act8945a_of_match[] = {
+	{ .compatible = "active-semi,act8945a", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, act8945a_of_match);
+
+static struct i2c_driver act8945a_i2c_driver = {
+	.driver = {
+		   .name = "act8945a",
+		   .of_match_table = act8945a_of_match,
+	},
+	.probe = act8945a_i2c_probe,
+	.id_table = act8945a_i2c_id,
+};
+
+static int __init act8945a_i2c_init(void)
+{
+	return i2c_add_driver(&act8945a_i2c_driver);
+}
+subsys_initcall(act8945a_i2c_init);
+
+static void __exit act8945a_i2c_exit(void)
+{
+	i2c_del_driver(&act8945a_i2c_driver);
+}
+module_exit(act8945a_i2c_exit);
+
+MODULE_DESCRIPTION("ACT8945A PMIC multi-function driver");
+MODULE_AUTHOR("Wenyou Yang <wenyou.yang@atmel.com>");
+MODULE_LICENSE("GPL");