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, 89 insertions, 0 deletions

diff --git a/security/integrity/evm/evm.h b/security/integrity/evm/evm.h
new file mode 100644
index 000000000..694552ace
--- /dev/null
+++ b/security/integrity/evm/evm.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2005-2010 IBM Corporation
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Kylene Hall <kjhall@us.ibm.com>
+ *
+ * File: evm.h
+ */
+
+#ifndef __INTEGRITY_EVM_H
+#define __INTEGRITY_EVM_H
+
+#include <linux/xattr.h>
+#include <linux/security.h>
+
+#include "../integrity.h"
+
+#define EVM_INIT_HMAC	0x0001
+#define EVM_INIT_X509	0x0002
+#define EVM_ALLOW_METADATA_WRITES	0x0004
+#define EVM_SIGV3_REQUIRED		0x0008
+#define EVM_SETUP_COMPLETE 0x80000000 /* userland has signaled key load */
+
+#define EVM_KEY_MASK (EVM_INIT_HMAC | EVM_INIT_X509)
+#define EVM_INIT_MASK (EVM_INIT_HMAC | EVM_INIT_X509 | EVM_SETUP_COMPLETE | \
+		       EVM_ALLOW_METADATA_WRITES | EVM_SIGV3_REQUIRED)
+
+struct xattr_list {
+	struct list_head list;
+	char *name;
+	bool enabled;
+};
+
+#define EVM_NEW_FILE			0x00000001
+#define EVM_IMMUTABLE_DIGSIG		0x00000002
+
+/* EVM integrity metadata associated with an inode */
+struct evm_iint_cache {
+	unsigned long flags;
+	enum integrity_status evm_status:4;
+	struct integrity_inode_attributes metadata_inode;
+};
+
+extern struct lsm_blob_sizes evm_blob_sizes;
+
+static inline struct evm_iint_cache *evm_iint_inode(const struct inode *inode)
+{
+	if (unlikely(!inode->i_security))
+		return NULL;
+
+	return inode->i_security + evm_blob_sizes.lbs_inode;
+}
+
+extern int evm_initialized;
+
+#define EVM_ATTR_FSUUID		0x0001
+
+extern int evm_hmac_attrs;
+
+/* List of EVM protected security xattrs */
+extern struct list_head evm_config_xattrnames;
+
+struct evm_digest {
+	struct ima_digest_data_hdr hdr;
+	char digest[IMA_MAX_DIGEST_SIZE];
+} __packed;
+
+int evm_protected_xattr(const char *req_xattr_name);
+
+int evm_init_key(void);
+int evm_update_evmxattr(struct dentry *dentry,
+			const char *req_xattr_name,
+			const char *req_xattr_value,
+			size_t req_xattr_value_len);
+int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
+		  const char *req_xattr_value,
+		  size_t req_xattr_value_len, struct evm_digest *data,
+		  struct evm_iint_cache *iint);
+int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name,
+		  const char *req_xattr_value,
+		  size_t req_xattr_value_len, char type,
+		  struct evm_digest *data, struct evm_iint_cache *iint);
+int evm_init_hmac(struct inode *inode, const struct xattr *xattrs,
+		  char *hmac_val);
+int evm_init_secfs(void);
+
+#endif