diff options
Diffstat (limited to 'fs/open.c')
-rw-r--r-- | fs/open.c | 157 |
1 files changed, 52 insertions, 105 deletions
diff --git a/fs/open.c b/fs/open.c index b0bae3a41825..59071f55bf7f 100644 --- a/fs/open.c +++ b/fs/open.c @@ -132,27 +132,27 @@ SYSCALL_DEFINE2(truncate, const char __user *, path, long, length) static long do_sys_ftruncate(unsigned int fd, loff_t length, int small) { - struct inode * inode; + struct inode *inode; struct dentry *dentry; - struct file * file; + struct fd f; int error; error = -EINVAL; if (length < 0) goto out; error = -EBADF; - file = fget(fd); - if (!file) + f = fdget(fd); + if (!f.file) goto out; /* explicitly opened as large or we are on 64-bit box */ - if (file->f_flags & O_LARGEFILE) + if (f.file->f_flags & O_LARGEFILE) small = 0; - dentry = file->f_path.dentry; + dentry = f.file->f_path.dentry; inode = dentry->d_inode; error = -EINVAL; - if (!S_ISREG(inode->i_mode) || !(file->f_mode & FMODE_WRITE)) + if (!S_ISREG(inode->i_mode) || !(f.file->f_mode & FMODE_WRITE)) goto out_putf; error = -EINVAL; @@ -165,14 +165,14 @@ static long do_sys_ftruncate(unsigned int fd, loff_t length, int small) goto out_putf; sb_start_write(inode->i_sb); - error = locks_verify_truncate(inode, file, length); + error = locks_verify_truncate(inode, f.file, length); if (!error) - error = security_path_truncate(&file->f_path); + error = security_path_truncate(&f.file->f_path); if (!error) - error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, file); + error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, f.file); sb_end_write(inode->i_sb); out_putf: - fput(file); + fdput(f); out: return error; } @@ -276,15 +276,13 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len) SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len) { - struct file *file; + struct fd f = fdget(fd); int error = -EBADF; - file = fget(fd); - if (file) { - error = do_fallocate(file, mode, offset, len); - fput(file); + if (f.file) { + error = do_fallocate(f.file, mode, offset, len); + fdput(f); } - return error; } @@ -400,16 +398,15 @@ out: SYSCALL_DEFINE1(fchdir, unsigned int, fd) { - struct file *file; + struct fd f = fdget_raw(fd); struct inode *inode; - int error, fput_needed; + int error = -EBADF; error = -EBADF; - file = fget_raw_light(fd, &fput_needed); - if (!file) + if (!f.file) goto out; - inode = file->f_path.dentry->d_inode; + inode = f.file->f_path.dentry->d_inode; error = -ENOTDIR; if (!S_ISDIR(inode->i_mode)) @@ -417,9 +414,9 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd) error = inode_permission(inode, MAY_EXEC | MAY_CHDIR); if (!error) - set_fs_pwd(current->fs, &file->f_path); + set_fs_pwd(current->fs, &f.file->f_path); out_putf: - fput_light(file, fput_needed); + fdput(f); out: return error; } @@ -481,7 +478,7 @@ SYSCALL_DEFINE2(fchmod, unsigned int, fd, umode_t, mode) file = fget(fd); if (file) { - audit_inode(NULL, file->f_path.dentry); + audit_inode(NULL, file->f_path.dentry, 0); err = chmod_common(&file->f_path, mode); fput(file); } @@ -582,23 +579,20 @@ SYSCALL_DEFINE3(lchown, const char __user *, filename, uid_t, user, gid_t, group SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group) { - struct file * file; + struct fd f = fdget(fd); int error = -EBADF; - struct dentry * dentry; - file = fget(fd); - if (!file) + if (!f.file) goto out; - error = mnt_want_write_file(file); + error = mnt_want_write_file(f.file); if (error) goto out_fput; - dentry = file->f_path.dentry; - audit_inode(NULL, dentry); - error = chown_common(&file->f_path, user, group); - mnt_drop_write_file(file); + audit_inode(NULL, f.file->f_path.dentry, 0); + error = chown_common(&f.file->f_path, user, group); + mnt_drop_write_file(f.file); out_fput: - fput(file); + fdput(f); out: return error; } @@ -803,50 +797,6 @@ struct file *dentry_open(const struct path *path, int flags, } EXPORT_SYMBOL(dentry_open); -static void __put_unused_fd(struct files_struct *files, unsigned int fd) -{ - struct fdtable *fdt = files_fdtable(files); - __clear_open_fd(fd, fdt); - if (fd < files->next_fd) - files->next_fd = fd; -} - -void put_unused_fd(unsigned int fd) -{ - struct files_struct *files = current->files; - spin_lock(&files->file_lock); - __put_unused_fd(files, fd); - spin_unlock(&files->file_lock); -} - -EXPORT_SYMBOL(put_unused_fd); - -/* - * Install a file pointer in the fd array. - * - * The VFS is full of places where we drop the files lock between - * setting the open_fds bitmap and installing the file in the file - * array. At any such point, we are vulnerable to a dup2() race - * installing a file in the array before us. We need to detect this and - * fput() the struct file we are about to overwrite in this case. - * - * It should never happen - if we allow dup2() do it, _really_ bad things - * will follow. - */ - -void fd_install(unsigned int fd, struct file *file) -{ - struct files_struct *files = current->files; - struct fdtable *fdt; - spin_lock(&files->file_lock); - fdt = files_fdtable(files); - BUG_ON(fdt->fd[fd] != NULL); - rcu_assign_pointer(fdt->fd[fd], file); - spin_unlock(&files->file_lock); -} - -EXPORT_SYMBOL(fd_install); - static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op) { int lookup_flags = 0; @@ -858,7 +808,7 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o op->mode = 0; /* Must never be set by userspace */ - flags &= ~FMODE_NONOTIFY; + flags &= ~FMODE_NONOTIFY & ~O_CLOEXEC; /* * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only @@ -909,6 +859,24 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o } /** + * file_open_name - open file and return file pointer + * + * @name: struct filename containing path to open + * @flags: open flags as per the open(2) second argument + * @mode: mode for the new file if O_CREAT is set, else ignored + * + * This is the helper to open a file from kernelspace if you really + * have to. But in generally you should not do this, so please move + * along, nothing to see here.. + */ +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); +} + +/** * filp_open - open file and return file pointer * * @filename: path to open @@ -921,9 +889,8 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o */ struct file *filp_open(const char *filename, int flags, umode_t mode) { - struct open_flags op; - int lookup = build_open_flags(flags, mode, &op); - return do_filp_open(AT_FDCWD, filename, &op, lookup); + struct filename name = {.name = filename}; + return file_open_name(&name, flags, mode); } EXPORT_SYMBOL(filp_open); @@ -945,7 +912,7 @@ 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); - char *tmp = getname(filename); + struct filename *tmp = getname(filename); int fd = PTR_ERR(tmp); if (!IS_ERR(tmp)) { @@ -1038,23 +1005,7 @@ EXPORT_SYMBOL(filp_close); */ SYSCALL_DEFINE1(close, unsigned int, fd) { - struct file * filp; - struct files_struct *files = current->files; - struct fdtable *fdt; - int retval; - - spin_lock(&files->file_lock); - fdt = files_fdtable(files); - if (fd >= fdt->max_fds) - goto out_unlock; - filp = fdt->fd[fd]; - if (!filp) - goto out_unlock; - rcu_assign_pointer(fdt->fd[fd], NULL); - __clear_close_on_exec(fd, fdt); - __put_unused_fd(files, fd); - spin_unlock(&files->file_lock); - retval = filp_close(filp, files); + int retval = __close_fd(current->files, fd); /* can't restart close syscall because file table entry was cleared */ if (unlikely(retval == -ERESTARTSYS || @@ -1064,10 +1015,6 @@ SYSCALL_DEFINE1(close, unsigned int, fd) retval = -EINTR; return retval; - -out_unlock: - spin_unlock(&files->file_lock); - return -EBADF; } EXPORT_SYMBOL(sys_close); |