diff options
| -rw-r--r-- | fs/Kconfig | 10 | ||||
| -rw-r--r-- | fs/locks.c | 2 | ||||
| -rw-r--r-- | fs/namespace.c | 10 | ||||
| -rw-r--r-- | include/linux/fs.h | 74 |
4 files changed, 62 insertions, 34 deletions
diff --git a/fs/Kconfig b/fs/Kconfig index da3f32f1a4e4..59322e6e76f4 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -67,6 +67,16 @@ config FILE_LOCKING for filesystems like NFS and for the flock() system call. Disabling this option saves about 11k. +config MANDATORY_FILE_LOCKING + bool "Enable Mandatory file locking" + depends on FILE_LOCKING + default y + help + This option enables files appropriately marked files on appropriely + mounted filesystems to support mandatory locking. + + To the best of my knowledge this is dead code that no one cares about. + source "fs/notify/Kconfig" source "fs/quota/Kconfig" diff --git a/fs/locks.c b/fs/locks.c index 0d2b3267e2a3..86c94674ab22 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1191,6 +1191,7 @@ static int posix_lock_inode_wait(struct inode *inode, struct file_lock *fl) return error; } +#ifdef CONFIG_MANDATORY_FILE_LOCKING /** * locks_mandatory_locked - Check for an active lock * @file: the file to check @@ -1289,6 +1290,7 @@ int locks_mandatory_area(int read_write, struct inode *inode, } EXPORT_SYMBOL(locks_mandatory_area); +#endif /* CONFIG_MANDATORY_FILE_LOCKING */ static void lease_clear_pending(struct file_lock *fl, int arg) { diff --git a/fs/namespace.c b/fs/namespace.c index 0570729c87fd..4219885e9681 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1584,6 +1584,14 @@ static inline bool may_mount(void) return ns_capable(current->nsproxy->mnt_ns->user_ns, CAP_SYS_ADMIN); } +static inline bool may_mandlock(void) +{ +#ifndef CONFIG_MANDATORY_FILE_LOCKING + return false; +#endif + return true; +} + /* * Now umount can handle mount points as well as block devices. * This is important for filesystems which use unnamed block devices. @@ -2677,6 +2685,8 @@ long do_mount(const char *dev_name, const char __user *dir_name, type_page, flags, data_page); if (!retval && !may_mount()) retval = -EPERM; + if (!retval && (flags & MS_MANDLOCK) && !may_mandlock()) + retval = -EPERM; if (retval) goto dput_out; diff --git a/include/linux/fs.h b/include/linux/fs.h index 3aa514254161..cbf08d5c246e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2030,7 +2030,7 @@ extern struct kobject *fs_kobj; #define FLOCK_VERIFY_READ 1 #define FLOCK_VERIFY_WRITE 2 -#ifdef CONFIG_FILE_LOCKING +#ifdef CONFIG_MANDATORY_FILE_LOCKING extern int locks_mandatory_locked(struct file *); extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t); @@ -2075,6 +2075,45 @@ static inline int locks_verify_truncate(struct inode *inode, return 0; } +#else /* !CONFIG_MANDATORY_FILE_LOCKING */ + +static inline int locks_mandatory_locked(struct file *file) +{ + return 0; +} + +static inline int locks_mandatory_area(int rw, struct inode *inode, + struct file *filp, loff_t offset, + size_t count) +{ + return 0; +} + +static inline int __mandatory_lock(struct inode *inode) +{ + return 0; +} + +static inline int mandatory_lock(struct inode *inode) +{ + return 0; +} + +static inline int locks_verify_locked(struct file *file) +{ + return 0; +} + +static inline int locks_verify_truncate(struct inode *inode, struct file *filp, + size_t size) +{ + return 0; +} + +#endif /* CONFIG_MANDATORY_FILE_LOCKING */ + + +#ifdef CONFIG_FILE_LOCKING static inline int break_lease(struct inode *inode, unsigned int mode) { /* @@ -2136,39 +2175,6 @@ static inline int break_layout(struct inode *inode, bool wait) } #else /* !CONFIG_FILE_LOCKING */ -static inline int locks_mandatory_locked(struct file *file) -{ - return 0; -} - -static inline int locks_mandatory_area(int rw, struct inode *inode, - struct file *filp, loff_t offset, - size_t count) -{ - return 0; -} - -static inline int __mandatory_lock(struct inode *inode) -{ - return 0; -} - -static inline int mandatory_lock(struct inode *inode) -{ - return 0; -} - -static inline int locks_verify_locked(struct file *file) -{ - return 0; -} - -static inline int locks_verify_truncate(struct inode *inode, struct file *filp, - size_t size) -{ - return 0; -} - static inline int break_lease(struct inode *inode, unsigned int mode) { return 0; |