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, 82 insertions, 0 deletions

diff --git a/drivers/dio/dio-sysfs.c b/drivers/dio/dio-sysfs.c
new file mode 100644
index 000000000..ee1a3b59b
--- /dev/null
+++ b/drivers/dio/dio-sysfs.c
@@ -0,0 +1,82 @@
+/*
+ *  File Attributes for DIO Devices
+ *
+ *  Copyright (C) 2004 Jochen Friedrich
+ *
+ *  Loosely based on drivers/pci/pci-sysfs.c and drivers/zorro/zorro-sysfs.c
+ *
+ *  This file is subject to the terms and conditions of the GNU General Public
+ *  License.  See the file COPYING in the main directory of this archive
+ *  for more details.
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/dio.h>
+#include <linux/stat.h>
+
+/* show configuration fields */
+
+static ssize_t dio_show_id(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dio_dev *d;
+
+	d = to_dio_dev(dev);
+	return sprintf(buf, "0x%02x\n", (d->id & 0xff));
+}
+static DEVICE_ATTR(id, S_IRUGO, dio_show_id, NULL);
+
+static ssize_t dio_show_ipl(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dio_dev *d;
+
+	d = to_dio_dev(dev);
+	return sprintf(buf, "0x%02x\n", d->ipl);
+}
+static DEVICE_ATTR(ipl, S_IRUGO, dio_show_ipl, NULL);
+
+static ssize_t dio_show_secid(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dio_dev *d;
+
+	d = to_dio_dev(dev);
+	return sprintf(buf, "0x%02x\n", ((d->id >> 8)& 0xff));
+}
+static DEVICE_ATTR(secid, S_IRUGO, dio_show_secid, NULL);
+
+static ssize_t dio_show_name(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dio_dev *d;
+
+	d = to_dio_dev(dev);
+	return sprintf(buf, "%s\n", d->name);
+}
+static DEVICE_ATTR(name, S_IRUGO, dio_show_name, NULL);
+
+static ssize_t dio_show_resource(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct dio_dev *d = to_dio_dev(dev);
+
+	return sprintf(buf, "0x%08lx 0x%08lx 0x%08lx\n",
+		       (unsigned long)dio_resource_start(d),
+		       (unsigned long)dio_resource_end(d),
+		       dio_resource_flags(d));
+}
+static DEVICE_ATTR(resource, S_IRUGO, dio_show_resource, NULL);
+
+int dio_create_sysfs_dev_files(struct dio_dev *d)
+{
+	struct device *dev = &d->dev;
+	int error;
+
+	/* current configuration's attributes */
+	if ((error = device_create_file(dev, &dev_attr_id)) ||
+	    (error = device_create_file(dev, &dev_attr_ipl)) ||
+	    (error = device_create_file(dev, &dev_attr_secid)) ||
+	    (error = device_create_file(dev, &dev_attr_name)) ||
+	    (error = device_create_file(dev, &dev_attr_resource)))
+		return error;
+
+	return 0;
+}
+