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, 69 insertions, 0 deletions

diff --git a/security/integrity/integrity_audit.c b/security/integrity/integrity_audit.c
new file mode 100644
index 000000000..d8d9e5ff1
--- /dev/null
+++ b/security/integrity/integrity_audit.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2008 IBM Corporation
+ * Author: Mimi Zohar <zohar@us.ibm.com>
+ *
+ * File: integrity_audit.c
+ *	Audit calls for the integrity subsystem
+ */
+
+#include <linux/fs.h>
+#include <linux/gfp.h>
+#include <linux/audit.h>
+#include "integrity.h"
+
+static int integrity_audit_info;
+
+/* ima_audit_setup - enable informational auditing messages */
+static int __init integrity_audit_setup(char *str)
+{
+	unsigned long audit;
+
+	if (!kstrtoul(str, 0, &audit))
+		integrity_audit_info = audit ? 1 : 0;
+	return 1;
+}
+__setup("integrity_audit=", integrity_audit_setup);
+
+void integrity_audit_msg(int audit_msgno, struct inode *inode,
+			 const unsigned char *fname, const char *op,
+			 const char *cause, int result, int audit_info)
+{
+	integrity_audit_message(audit_msgno, inode, fname, op, cause,
+				result, audit_info, 0);
+}
+
+void integrity_audit_message(int audit_msgno, struct inode *inode,
+			     const unsigned char *fname, const char *op,
+			     const char *cause, int result, int audit_info,
+			     int errno)
+{
+	struct audit_buffer *ab;
+	char name[TASK_COMM_LEN];
+
+	if (!integrity_audit_info && audit_info == 1)	/* Skip info messages */
+		return;
+
+	ab = audit_log_start(audit_context(), GFP_KERNEL, audit_msgno);
+	if (!ab)
+		return;
+	audit_log_format(ab, "pid=%d uid=%u auid=%u ses=%u",
+			 task_pid_nr(current),
+			 from_kuid(&init_user_ns, current_uid()),
+			 from_kuid(&init_user_ns, audit_get_loginuid(current)),
+			 audit_get_sessionid(current));
+	audit_log_task_context(ab);
+	audit_log_format(ab, " op=%s cause=%s comm=", op, cause);
+	audit_log_untrustedstring(ab, get_task_comm(name, current));
+	if (fname) {
+		audit_log_format(ab, " name=");
+		audit_log_untrustedstring(ab, fname);
+	}
+	if (inode) {
+		audit_log_format(ab, " dev=");
+		audit_log_untrustedstring(ab, inode->i_sb->s_id);
+		audit_log_format(ab, " ino=%llu", inode->i_ino);
+	}
+	audit_log_format(ab, " res=%d errno=%d", !result, errno);
+	audit_log_end(ab);
+}