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/jffs2/security.c | 73 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 fs/jffs2/security.c (limited to 'fs/jffs2/security.c') diff --git a/fs/jffs2/security.c b/fs/jffs2/security.c new file mode 100644 index 000000000..437f3a2c1 --- /dev/null +++ b/fs/jffs2/security.c @@ -0,0 +1,73 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright © 2006 NEC Corporation + * + * Created by KaiGai Kohei + * + * For licensing information, see the file 'LICENCE' in this directory. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "nodelist.h" + +/* ---- Initial Security Label(s) Attachment callback --- */ +static int jffs2_initxattrs(struct inode *inode, + const struct xattr *xattr_array, void *fs_info) +{ + const struct xattr *xattr; + int err = 0; + + for (xattr = xattr_array; xattr->name != NULL; xattr++) { + err = do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY, + xattr->name, xattr->value, + xattr->value_len, 0); + if (err < 0) + break; + } + return err; +} + +/* ---- Initial Security Label(s) Attachment ----------- */ +int jffs2_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr) +{ + return security_inode_init_security(inode, dir, qstr, + &jffs2_initxattrs, NULL); +} + +/* ---- XATTR Handler for "security.*" ----------------- */ +static int jffs2_security_getxattr(const struct xattr_handler *handler, + struct dentry *unused, struct inode *inode, + const char *name, void *buffer, size_t size) +{ + return do_jffs2_getxattr(inode, JFFS2_XPREFIX_SECURITY, + name, buffer, size); +} + +static int jffs2_security_setxattr(const struct xattr_handler *handler, + struct mnt_idmap *idmap, + struct dentry *unused, struct inode *inode, + const char *name, const void *buffer, + size_t size, int flags) +{ + return do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY, + name, buffer, size, flags); +} + +const struct xattr_handler jffs2_security_xattr_handler = { + .prefix = XATTR_SECURITY_PREFIX, + .set = jffs2_security_setxattr, + .get = jffs2_security_getxattr +}; -- cgit v1.3.1