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, 78 insertions, 0 deletions

diff --git a/fs/udf/udfend.h b/fs/udf/udfend.h
new file mode 100644
index 000000000..a4363ac2c
--- /dev/null
+++ b/fs/udf/udfend.h
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __UDF_ENDIAN_H
+#define __UDF_ENDIAN_H
+
+#include <asm/byteorder.h>
+#include <linux/string.h>
+
+static inline struct kernel_lb_addr lelb_to_cpu(struct lb_addr in)
+{
+	struct kernel_lb_addr out;
+
+	out.logicalBlockNum = le32_to_cpu(in.logicalBlockNum);
+	out.partitionReferenceNum = le16_to_cpu(in.partitionReferenceNum);
+
+	return out;
+}
+
+static inline struct lb_addr cpu_to_lelb(struct kernel_lb_addr in)
+{
+	struct lb_addr out;
+
+	out.logicalBlockNum = cpu_to_le32(in.logicalBlockNum);
+	out.partitionReferenceNum = cpu_to_le16(in.partitionReferenceNum);
+
+	return out;
+}
+
+static inline struct short_ad lesa_to_cpu(struct short_ad in)
+{
+	struct short_ad out;
+
+	out.extLength = le32_to_cpu(in.extLength);
+	out.extPosition = le32_to_cpu(in.extPosition);
+
+	return out;
+}
+
+static inline struct short_ad cpu_to_lesa(struct short_ad in)
+{
+	struct short_ad out;
+
+	out.extLength = cpu_to_le32(in.extLength);
+	out.extPosition = cpu_to_le32(in.extPosition);
+
+	return out;
+}
+
+static inline struct kernel_long_ad lela_to_cpu(struct long_ad in)
+{
+	struct kernel_long_ad out;
+
+	out.extLength = le32_to_cpu(in.extLength);
+	out.extLocation = lelb_to_cpu(in.extLocation);
+
+	return out;
+}
+
+static inline struct long_ad cpu_to_lela(struct kernel_long_ad in)
+{
+	struct long_ad out;
+
+	out.extLength = cpu_to_le32(in.extLength);
+	out.extLocation = cpu_to_lelb(in.extLocation);
+
+	return out;
+}
+
+static inline struct kernel_extent_ad leea_to_cpu(struct extent_ad in)
+{
+	struct kernel_extent_ad out;
+
+	out.extLength = le32_to_cpu(in.extLength);
+	out.extLocation = le32_to_cpu(in.extLocation);
+
+	return out;
+}
+
+#endif /* __UDF_ENDIAN_H */