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, 71 insertions, 0 deletions

diff --git a/security/integrity/iint.c b/security/integrity/iint.c
new file mode 100644
index 000000000..8ec1a3436
--- /dev/null
+++ b/security/integrity/iint.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2008 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ *
+ * File: integrity_iint.c
+ *	- initialize the integrity directory in securityfs
+ *	- load IMA and EVM keys
+ */
+#include <linux/security.h>
+#include "integrity.h"
+
+struct dentry *integrity_dir;
+
+/*
+ * integrity_kernel_read - read data from the file
+ *
+ * This is a function for reading file content instead of kernel_read().
+ * It does not perform locking checks to ensure it cannot be blocked.
+ * It does not perform security checks because it is irrelevant for IMA.
+ *
+ */
+int integrity_kernel_read(struct file *file, loff_t offset,
+			  void *addr, unsigned long count)
+{
+	return __kernel_read(file, addr, count, &offset);
+}
+
+/*
+ * integrity_load_keys - load integrity keys hook
+ *
+ * Hooks is called from init/main.c:kernel_init_freeable()
+ * when rootfs is ready
+ */
+void __init integrity_load_keys(void)
+{
+	ima_load_x509();
+
+	if (!IS_ENABLED(CONFIG_IMA_LOAD_X509))
+		evm_load_x509();
+}
+
+int __init integrity_fs_init(void)
+{
+	if (integrity_dir)
+		return 0;
+
+	integrity_dir = securityfs_create_dir("integrity", NULL);
+	if (IS_ERR(integrity_dir)) {
+		int ret = PTR_ERR(integrity_dir);
+
+		if (ret != -ENODEV)
+			pr_err("Unable to create integrity sysfs dir: %d\n",
+			       ret);
+		integrity_dir = NULL;
+		return ret;
+	}
+
+	return 0;
+}
+
+void __init integrity_fs_fini(void)
+{
+	if (!integrity_dir || !simple_empty(integrity_dir))
+		return;
+
+	securityfs_remove(integrity_dir);
+	integrity_dir = NULL;
+}