From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops 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 --- fs/romfs/internal.h | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 fs/romfs/internal.h (limited to 'fs/romfs/internal.h') diff --git a/fs/romfs/internal.h b/fs/romfs/internal.h new file mode 100644 index 000000000..e90df22bd --- /dev/null +++ b/fs/romfs/internal.h @@ -0,0 +1,43 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* RomFS internal definitions + * + * Copyright © 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include + +struct romfs_inode_info { + struct inode vfs_inode; + unsigned long i_metasize; /* size of non-data area */ + unsigned long i_dataoffset; /* from the start of fs */ +}; + +static inline size_t romfs_maxsize(struct super_block *sb) +{ + return (size_t) (unsigned long) sb->s_fs_info; +} + +static inline struct romfs_inode_info *ROMFS_I(struct inode *inode) +{ + return container_of(inode, struct romfs_inode_info, vfs_inode); +} + +/* + * mmap-nommu.c + */ +#if !defined(CONFIG_MMU) && defined(CONFIG_ROMFS_ON_MTD) +extern const struct file_operations romfs_ro_fops; +#else +#define romfs_ro_fops generic_ro_fops +#endif + +/* + * storage.c + */ +extern int romfs_dev_read(struct super_block *sb, unsigned long pos, + void *buf, size_t buflen); +extern ssize_t romfs_dev_strnlen(struct super_block *sb, + unsigned long pos, size_t maxlen); +extern int romfs_dev_strcmp(struct super_block *sb, unsigned long pos, + const char *str, size_t size); -- cgit v1.3.1