diff options
Diffstat (limited to 'fs/open.c')
| -rw-r--r-- | fs/open.c | 288 |
1 files changed, 143 insertions, 145 deletions
diff --git a/fs/open.c b/fs/open.c index 68354466879..d6fd3acde13 100644 --- a/fs/open.c +++ b/fs/open.c @@ -57,7 +57,8 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, newattrs.ia_valid |= ret | ATTR_FORCE; mutex_lock(&dentry->d_inode->i_mutex); - ret = notify_change(dentry, &newattrs); + /* Note any delegations or leases have already been broken: */ + ret = notify_change(dentry, &newattrs, NULL); mutex_unlock(&dentry->d_inode->i_mutex); return ret; } @@ -197,10 +198,7 @@ out: SYSCALL_DEFINE2(ftruncate, unsigned int, fd, unsigned long, length) { - long ret = do_sys_ftruncate(fd, length, 1); - /* avoid REGPARM breakage on x86: */ - asmlinkage_protect(2, ret, fd, length); - return ret; + return do_sys_ftruncate(fd, length, 1); } #ifdef CONFIG_COMPAT @@ -212,32 +210,15 @@ COMPAT_SYSCALL_DEFINE2(ftruncate, unsigned int, fd, compat_ulong_t, length) /* LFS versions of truncate are only needed on 32 bit machines */ #if BITS_PER_LONG == 32 -SYSCALL_DEFINE(truncate64)(const char __user * path, loff_t length) +SYSCALL_DEFINE2(truncate64, const char __user *, path, loff_t, length) { return do_sys_truncate(path, length); } -#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS -asmlinkage long SyS_truncate64(long path, loff_t length) -{ - return SYSC_truncate64((const char __user *) path, length); -} -SYSCALL_ALIAS(sys_truncate64, SyS_truncate64); -#endif -SYSCALL_DEFINE(ftruncate64)(unsigned int fd, loff_t length) +SYSCALL_DEFINE2(ftruncate64, unsigned int, fd, loff_t, length) { - long ret = do_sys_ftruncate(fd, length, 0); - /* avoid REGPARM breakage on x86: */ - asmlinkage_protect(2, ret, fd, length); - return ret; + return do_sys_ftruncate(fd, length, 0); } -#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS -asmlinkage long SyS_ftruncate64(long fd, loff_t length) -{ - return SYSC_ftruncate64((unsigned int) fd, length); -} -SYSCALL_ALIAS(sys_ftruncate64, SyS_ftruncate64); -#endif #endif /* BITS_PER_LONG == 32 */ @@ -250,7 +231,13 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len) return -EINVAL; /* Return error if mode is not supported */ - if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) + if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | + FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE)) + return -EOPNOTSUPP; + + /* Punch hole and zero range are mutually exclusive */ + if ((mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE)) == + (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE)) return -EOPNOTSUPP; /* Punch hole must have keep size set */ @@ -258,17 +245,30 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len) !(mode & FALLOC_FL_KEEP_SIZE)) return -EOPNOTSUPP; + /* Collapse range should only be used exclusively. */ + if ((mode & FALLOC_FL_COLLAPSE_RANGE) && + (mode & ~FALLOC_FL_COLLAPSE_RANGE)) + return -EINVAL; + if (!(file->f_mode & FMODE_WRITE)) return -EBADF; - /* It's not possible punch hole on append only file */ - if (mode & FALLOC_FL_PUNCH_HOLE && IS_APPEND(inode)) + /* + * We can only allow pure fallocate on append only files + */ + if ((mode & ~FALLOC_FL_KEEP_SIZE) && IS_APPEND(inode)) return -EPERM; if (IS_IMMUTABLE(inode)) return -EPERM; /* + * We cannot allow any fallocate operation on an active swapfile + */ + if (IS_SWAPFILE(inode)) + return -ETXTBSY; + + /* * Revalidate the write permissions, in case security policy has * changed since the files were opened. */ @@ -299,7 +299,7 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len) return ret; } -SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len) +SYSCALL_DEFINE4(fallocate, int, fd, int, mode, loff_t, offset, loff_t, len) { struct fd f = fdget(fd); int error = -EBADF; @@ -311,14 +311,6 @@ SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len) return error; } -#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS -asmlinkage long SyS_fallocate(long fd, long mode, loff_t offset, loff_t len) -{ - return SYSC_fallocate((int)fd, (int)mode, offset, len); -} -SYSCALL_ALIAS(sys_fallocate, SyS_fallocate); -#endif - /* * access() needs to use the real uid/gid, not the effective uid/gid. * We do this by temporarily clearing all FS-related capabilities and @@ -471,7 +463,7 @@ retry: goto dput_and_out; error = -EPERM; - if (!nsown_capable(CAP_SYS_CHROOT)) + if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT)) goto dput_and_out; error = security_path_chroot(&path); if (error) @@ -492,35 +484,41 @@ out: static int chmod_common(struct path *path, umode_t mode) { struct inode *inode = path->dentry->d_inode; + struct inode *delegated_inode = NULL; struct iattr newattrs; int error; error = mnt_want_write(path->mnt); if (error) return error; +retry_deleg: mutex_lock(&inode->i_mutex); error = security_path_chmod(path, mode); if (error) goto out_unlock; newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; - error = notify_change(path->dentry, &newattrs); + error = notify_change(path->dentry, &newattrs, &delegated_inode); out_unlock: mutex_unlock(&inode->i_mutex); + if (delegated_inode) { + error = break_deleg_wait(&delegated_inode); + if (!error) + goto retry_deleg; + } mnt_drop_write(path->mnt); return error; } SYSCALL_DEFINE2(fchmod, unsigned int, fd, umode_t, mode) { - struct file * file; + struct fd f = fdget(fd); int err = -EBADF; - file = fget(fd); - if (file) { - audit_inode(NULL, file->f_path.dentry, 0); - err = chmod_common(&file->f_path, mode); - fput(file); + if (f.file) { + audit_inode(NULL, f.file->f_path.dentry, 0); + err = chmod_common(&f.file->f_path, mode); + fdput(f); } return err; } @@ -551,6 +549,7 @@ SYSCALL_DEFINE2(chmod, const char __user *, filename, umode_t, mode) static int chown_common(struct path *path, uid_t user, gid_t group) { struct inode *inode = path->dentry->d_inode; + struct inode *delegated_inode = NULL; int error; struct iattr newattrs; kuid_t uid; @@ -575,12 +574,17 @@ static int chown_common(struct path *path, uid_t user, gid_t group) if (!S_ISDIR(inode->i_mode)) newattrs.ia_valid |= ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV; +retry_deleg: mutex_lock(&inode->i_mutex); error = security_path_chown(path, uid, gid); if (!error) - error = notify_change(path->dentry, &newattrs); + error = notify_change(path->dentry, &newattrs, &delegated_inode); mutex_unlock(&inode->i_mutex); - + if (delegated_inode) { + error = break_deleg_wait(&delegated_inode); + if (!error) + goto retry_deleg; + } return error; } @@ -647,35 +651,6 @@ out: return error; } -/* - * You have to be very careful that these write - * counts get cleaned up in error cases and - * upon __fput(). This should probably never - * be called outside of __dentry_open(). - */ -static inline int __get_file_write_access(struct inode *inode, - struct vfsmount *mnt) -{ - int error; - error = get_write_access(inode); - if (error) - return error; - /* - * Do not take mount writer counts on - * special files since no writes to - * the mount itself will occur. - */ - if (!special_file(inode->i_mode)) { - /* - * Balanced in __fput() - */ - error = __mnt_want_write(mnt); - if (error) - put_write_access(inode); - } - return error; -} - int open_check_o_direct(struct file *f) { /* NB: we're sure to have correct a_ops only after f_op->open */ @@ -700,28 +675,37 @@ static int do_dentry_open(struct file *f, f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE; - if (unlikely(f->f_flags & O_PATH)) - f->f_mode = FMODE_PATH; - path_get(&f->f_path); inode = f->f_inode = f->f_path.dentry->d_inode; - if (f->f_mode & FMODE_WRITE) { - error = __get_file_write_access(inode, f->f_path.mnt); - if (error) - goto cleanup_file; - if (!special_file(inode->i_mode)) - file_take_write(f); - } - f->f_mapping = inode->i_mapping; - file_sb_list_add(f, inode->i_sb); - if (unlikely(f->f_mode & FMODE_PATH)) { + if (unlikely(f->f_flags & O_PATH)) { + f->f_mode = FMODE_PATH; f->f_op = &empty_fops; return 0; } + if (f->f_mode & FMODE_WRITE && !special_file(inode->i_mode)) { + error = get_write_access(inode); + if (unlikely(error)) + goto cleanup_file; + error = __mnt_want_write(f->f_path.mnt); + if (unlikely(error)) { + put_write_access(inode); + goto cleanup_file; + } + f->f_mode |= FMODE_WRITER; + } + + /* POSIX.1-2008/SUSv4 Section XSI 2.9.7 */ + if (S_ISREG(inode->i_mode)) + f->f_mode |= FMODE_ATOMIC_POS; + f->f_op = fops_get(inode->i_fop); + if (unlikely(WARN_ON(!f->f_op))) { + error = -ENODEV; + goto cleanup_all; + } error = security_file_open(f, cred); if (error) @@ -731,7 +715,7 @@ static int do_dentry_open(struct file *f, if (error) goto cleanup_all; - if (!open && f->f_op) + if (!open) open = f->f_op->open; if (open) { error = open(inode, f); @@ -740,6 +724,12 @@ static int do_dentry_open(struct file *f, } if ((f->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) i_readcount_inc(inode); + if ((f->f_mode & FMODE_READ) && + likely(f->f_op->read || f->f_op->aio_read || f->f_op->read_iter)) + f->f_mode |= FMODE_CAN_READ; + if ((f->f_mode & FMODE_WRITE) && + likely(f->f_op->write || f->f_op->aio_write || f->f_op->write_iter)) + f->f_mode |= FMODE_CAN_WRITE; f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); @@ -749,19 +739,9 @@ static int do_dentry_open(struct file *f, cleanup_all: fops_put(f->f_op); - file_sb_list_del(f); - if (f->f_mode & FMODE_WRITE) { + if (f->f_mode & FMODE_WRITER) { put_write_access(inode); - if (!special_file(inode->i_mode)) { - /* - * We don't consider this a real - * mnt_want/drop_write() pair - * because it all happenend right - * here, so just reset the state. - */ - file_reset_write(f); - __mnt_drop_write(f->f_path.mnt); - } + __mnt_drop_write(f->f_path.mnt); } cleanup_file: path_put(&f->f_path); @@ -773,14 +753,24 @@ cleanup_file: /** * finish_open - finish opening a file - * @od: opaque open data + * @file: file pointer * @dentry: pointer to dentry * @open: open callback + * @opened: state of open * * This can be used to finish opening a file passed to i_op->atomic_open(). * * If the open callback is set to NULL, then the standard f_op->open() * filesystem callback is substituted. + * + * NB: the dentry reference is _not_ consumed. If, for example, the dentry is + * the return value of d_splice_alias(), then the caller needs to perform dput() + * on it after finish_open(). + * + * On successful return @file is a fully instantiated open file. After this, if + * an error occurs in ->atomic_open(), it needs to clean up with fput(). + * + * Returns zero on success or -errno if the open failed. */ int finish_open(struct file *file, struct dentry *dentry, int (*open)(struct inode *, struct file *), @@ -801,11 +791,16 @@ EXPORT_SYMBOL(finish_open); /** * finish_no_open - finish ->atomic_open() without opening the file * - * @od: opaque open data + * @file: file pointer * @dentry: dentry or NULL (as returned from ->lookup()) * * This can be used to set the result of a successful lookup in ->atomic_open(). - * The filesystem's atomic_open() method shall return NULL after calling this. + * + * NB: unlike finish_open() this function does consume the dentry reference and + * the caller need not dput() it. + * + * Returns "1" which must be the return value of ->atomic_open() after having + * called this function. */ int finish_no_open(struct file *file, struct dentry *dentry) { @@ -851,7 +846,7 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o int lookup_flags = 0; int acc_mode; - if (flags & O_CREAT) + if (flags & (O_CREAT | __O_TMPFILE)) op->mode = (mode & S_IALLUGO) | S_IFREG; else op->mode = 0; @@ -868,11 +863,17 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o if (flags & __O_SYNC) flags |= O_DSYNC; - /* - * If we have O_PATH in the open flag. Then we - * cannot have anything other than the below set of flags - */ - if (flags & O_PATH) { + if (flags & __O_TMPFILE) { + if ((flags & O_TMPFILE_MASK) != O_TMPFILE) + return -EINVAL; + acc_mode = MAY_OPEN | ACC_MODE(flags); + if (!(acc_mode & MAY_WRITE)) + return -EINVAL; + } else if (flags & O_PATH) { + /* + * If we have O_PATH in the open flag. Then we + * cannot have anything other than the below set of flags + */ flags &= O_DIRECTORY | O_NOFOLLOW | O_PATH; acc_mode = 0; } else { @@ -904,7 +905,8 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o lookup_flags |= LOOKUP_DIRECTORY; if (!(flags & O_NOFOLLOW)) lookup_flags |= LOOKUP_FOLLOW; - return lookup_flags; + op->lookup_flags = lookup_flags; + return 0; } /** @@ -921,8 +923,8 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o struct file *file_open_name(struct filename *name, int flags, umode_t mode) { struct open_flags op; - int lookup = build_open_flags(flags, mode, &op); - return do_filp_open(AT_FDCWD, name, &op, lookup); + int err = build_open_flags(flags, mode, &op); + return err ? ERR_PTR(err) : do_filp_open(AT_FDCWD, name, &op); } /** @@ -947,65 +949,61 @@ struct file *file_open_root(struct dentry *dentry, struct vfsmount *mnt, const char *filename, int flags) { struct open_flags op; - int lookup = build_open_flags(flags, 0, &op); + int err = build_open_flags(flags, 0, &op); + if (err) + return ERR_PTR(err); if (flags & O_CREAT) return ERR_PTR(-EINVAL); if (!filename && (flags & O_DIRECTORY)) if (!dentry->d_inode->i_op->lookup) return ERR_PTR(-ENOTDIR); - return do_file_open_root(dentry, mnt, filename, &op, lookup); + return do_file_open_root(dentry, mnt, filename, &op); } EXPORT_SYMBOL(file_open_root); long do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode) { struct open_flags op; - int lookup = build_open_flags(flags, mode, &op); - struct filename *tmp = getname(filename); - int fd = PTR_ERR(tmp); - - if (!IS_ERR(tmp)) { - fd = get_unused_fd_flags(flags); - if (fd >= 0) { - struct file *f = do_filp_open(dfd, tmp, &op, lookup); - if (IS_ERR(f)) { - put_unused_fd(fd); - fd = PTR_ERR(f); - } else { - fsnotify_open(f); - fd_install(fd, f); - } + int fd = build_open_flags(flags, mode, &op); + struct filename *tmp; + + if (fd) + return fd; + + tmp = getname(filename); + if (IS_ERR(tmp)) + return PTR_ERR(tmp); + + fd = get_unused_fd_flags(flags); + if (fd >= 0) { + struct file *f = do_filp_open(dfd, tmp, &op); + if (IS_ERR(f)) { + put_unused_fd(fd); + fd = PTR_ERR(f); + } else { + fsnotify_open(f); + fd_install(fd, f); } - putname(tmp); } + putname(tmp); return fd; } SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, umode_t, mode) { - long ret; - if (force_o_largefile()) flags |= O_LARGEFILE; - ret = do_sys_open(AT_FDCWD, filename, flags, mode); - /* avoid REGPARM breakage on x86: */ - asmlinkage_protect(3, ret, filename, flags, mode); - return ret; + return do_sys_open(AT_FDCWD, filename, flags, mode); } SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, flags, umode_t, mode) { - long ret; - if (force_o_largefile()) flags |= O_LARGEFILE; - ret = do_sys_open(dfd, filename, flags, mode); - /* avoid REGPARM breakage on x86: */ - asmlinkage_protect(4, ret, dfd, filename, flags, mode); - return ret; + return do_sys_open(dfd, filename, flags, mode); } #ifndef __alpha__ @@ -1034,7 +1032,7 @@ int filp_close(struct file *filp, fl_owner_t id) return 0; } - if (filp->f_op && filp->f_op->flush) + if (filp->f_op->flush) retval = filp->f_op->flush(filp, id); if (likely(!(filp->f_mode & FMODE_PATH))) { |
