ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.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