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, 184 insertions, 0 deletions

diff --git a/drivers/acpi/event.c b/drivers/acpi/event.c
new file mode 100644
index 000000000..4d840d2e7
--- /dev/null
+++ b/drivers/acpi/event.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * event.c - exporting ACPI events via procfs
+ *
+ *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ *
+ */
+
+#define pr_fmt(fmt) "ACPI: " fmt
+
+#include <linux/spinlock.h>
+#include <linux/export.h>
+#include <linux/proc_fs.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/gfp.h>
+#include <linux/acpi.h>
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include "internal.h"
+
+/* ACPI notifier chain */
+static BLOCKING_NOTIFIER_HEAD(acpi_chain_head);
+
+int acpi_notifier_call_chain(const char *device_class,
+			     const char *bus_id, u32 type, u32 data)
+{
+	struct acpi_bus_event event;
+
+	strscpy(event.device_class, device_class);
+	strscpy(event.bus_id, bus_id);
+	event.type = type;
+	event.data = data;
+	return (blocking_notifier_call_chain(&acpi_chain_head, 0, (void *)&event)
+			== NOTIFY_BAD) ? -EINVAL : 0;
+}
+EXPORT_SYMBOL(acpi_notifier_call_chain);
+
+int register_acpi_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&acpi_chain_head, nb);
+}
+EXPORT_SYMBOL(register_acpi_notifier);
+
+int unregister_acpi_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&acpi_chain_head, nb);
+}
+EXPORT_SYMBOL(unregister_acpi_notifier);
+
+#ifdef CONFIG_NET
+static unsigned int acpi_event_seqnum;
+struct acpi_genl_event {
+	acpi_device_class device_class;
+	char bus_id[15];
+	u32 type;
+	u32 data;
+};
+
+/* attributes of acpi_genl_family */
+enum {
+	ACPI_GENL_ATTR_UNSPEC,
+	ACPI_GENL_ATTR_EVENT,	/* ACPI event info needed by user space */
+	__ACPI_GENL_ATTR_MAX,
+};
+#define ACPI_GENL_ATTR_MAX (__ACPI_GENL_ATTR_MAX - 1)
+
+/* commands supported by the acpi_genl_family */
+enum {
+	ACPI_GENL_CMD_UNSPEC,
+	ACPI_GENL_CMD_EVENT,	/* kernel->user notifications for ACPI events */
+	__ACPI_GENL_CMD_MAX,
+};
+#define ACPI_GENL_CMD_MAX (__ACPI_GENL_CMD_MAX - 1)
+
+#define ACPI_GENL_FAMILY_NAME		"acpi_event"
+#define ACPI_GENL_VERSION		0x01
+#define ACPI_GENL_MCAST_GROUP_NAME 	"acpi_mc_group"
+
+static const struct genl_multicast_group acpi_event_mcgrps[] = {
+	{ .name = ACPI_GENL_MCAST_GROUP_NAME, },
+};
+
+static struct genl_family acpi_event_genl_family __ro_after_init = {
+	.module = THIS_MODULE,
+	.name = ACPI_GENL_FAMILY_NAME,
+	.version = ACPI_GENL_VERSION,
+	.maxattr = ACPI_GENL_ATTR_MAX,
+	.mcgrps = acpi_event_mcgrps,
+	.n_mcgrps = ARRAY_SIZE(acpi_event_mcgrps),
+};
+
+int acpi_bus_generate_netlink_event(const char *device_class,
+				      const char *bus_id,
+				      u8 type, int data)
+{
+	struct sk_buff *skb;
+	struct nlattr *attr;
+	struct acpi_genl_event *event;
+	void *msg_header;
+	int size;
+
+	/* allocate memory */
+	size = nla_total_size(sizeof(struct acpi_genl_event)) +
+	    nla_total_size(0);
+
+	skb = genlmsg_new(size, GFP_ATOMIC);
+	if (!skb)
+		return -ENOMEM;
+
+	/* add the genetlink message header */
+	msg_header = genlmsg_put(skb, 0, acpi_event_seqnum++,
+				 &acpi_event_genl_family, 0,
+				 ACPI_GENL_CMD_EVENT);
+	if (!msg_header) {
+		nlmsg_free(skb);
+		return -ENOMEM;
+	}
+
+	/* fill the data */
+	attr =
+	    nla_reserve(skb, ACPI_GENL_ATTR_EVENT,
+			sizeof(struct acpi_genl_event));
+	if (!attr) {
+		nlmsg_free(skb);
+		return -EINVAL;
+	}
+
+	event = nla_data(attr);
+	memset(event, 0, sizeof(struct acpi_genl_event));
+
+	strscpy(event->device_class, device_class, sizeof(event->device_class));
+	strscpy(event->bus_id, bus_id, sizeof(event->bus_id));
+	event->type = type;
+	event->data = data;
+
+	/* send multicast genetlink message */
+	genlmsg_end(skb, msg_header);
+
+	genlmsg_multicast(&acpi_event_genl_family, skb, 0, 0, GFP_ATOMIC);
+	return 0;
+}
+
+EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
+
+static int __init acpi_event_genetlink_init(void)
+{
+	return genl_register_family(&acpi_event_genl_family);
+}
+
+#else
+int acpi_bus_generate_netlink_event(const char *device_class,
+				      const char *bus_id,
+				      u8 type, int data)
+{
+	return 0;
+}
+
+EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
+
+static int acpi_event_genetlink_init(void)
+{
+	return -ENODEV;
+}
+#endif
+
+static int __init acpi_event_init(void)
+{
+	int error;
+
+	if (acpi_disabled)
+		return 0;
+
+	/* create genetlink for acpi event */
+	error = acpi_event_genetlink_init();
+	if (error)
+		pr_warn("Failed to create genetlink family for ACPI event\n");
+
+	return 0;
+}
+
+fs_initcall(acpi_event_init);