diff options
Diffstat (limited to 'fs')
-rw-r--r-- | fs/fuse/file.c | 132 | ||||
-rw-r--r-- | fs/fuse/fuse_i.h | 4 | ||||
-rw-r--r-- | fs/fuse/inode.c | 20 |
3 files changed, 154 insertions, 2 deletions
diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 1d59af306b28..d9a8289297c0 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -160,6 +160,18 @@ static int fuse_release(struct inode *inode, struct file *file) return fuse_release_common(inode, file, 0); } +/* + * It would be nice to scramble the ID space, so that the value of the + * files_struct pointer is not exposed to userspace. Symmetric crypto + * functions are overkill, since the inverse function doesn't need to + * be implemented (though it does have to exist). Is there something + * simpler? + */ +static inline u64 fuse_lock_owner_id(fl_owner_t id) +{ + return (unsigned long) id; +} + static int fuse_flush(struct file *file, fl_owner_t id) { struct inode *inode = file->f_dentry->d_inode; @@ -181,11 +193,13 @@ static int fuse_flush(struct file *file, fl_owner_t id) memset(&inarg, 0, sizeof(inarg)); inarg.fh = ff->fh; + inarg.lock_owner = fuse_lock_owner_id(id); req->in.h.opcode = FUSE_FLUSH; req->in.h.nodeid = get_node_id(inode); req->in.numargs = 1; req->in.args[0].size = sizeof(inarg); req->in.args[0].value = &inarg; + req->force = 1; request_send(fc, req); err = req->out.h.error; fuse_put_request(fc, req); @@ -604,6 +618,122 @@ static int fuse_set_page_dirty(struct page *page) return 0; } +static int convert_fuse_file_lock(const struct fuse_file_lock *ffl, + struct file_lock *fl) +{ + switch (ffl->type) { + case F_UNLCK: + break; + + case F_RDLCK: + case F_WRLCK: + if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX || + ffl->end < ffl->start) + return -EIO; + + fl->fl_start = ffl->start; + fl->fl_end = ffl->end; + fl->fl_pid = ffl->pid; + break; + + default: + return -EIO; + } + fl->fl_type = ffl->type; + return 0; +} + +static void fuse_lk_fill(struct fuse_req *req, struct file *file, + const struct file_lock *fl, int opcode, pid_t pid) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_file *ff = file->private_data; + struct fuse_lk_in *arg = &req->misc.lk_in; + + arg->fh = ff->fh; + arg->owner = fuse_lock_owner_id(fl->fl_owner); + arg->lk.start = fl->fl_start; + arg->lk.end = fl->fl_end; + arg->lk.type = fl->fl_type; + arg->lk.pid = pid; + req->in.h.opcode = opcode; + req->in.h.nodeid = get_node_id(inode); + req->in.numargs = 1; + req->in.args[0].size = sizeof(*arg); + req->in.args[0].value = arg; +} + +static int fuse_getlk(struct file *file, struct file_lock *fl) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_req *req; + struct fuse_lk_out outarg; + int err; + + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); + + fuse_lk_fill(req, file, fl, FUSE_GETLK, 0); + req->out.numargs = 1; + req->out.args[0].size = sizeof(outarg); + req->out.args[0].value = &outarg; + request_send(fc, req); + err = req->out.h.error; + fuse_put_request(fc, req); + if (!err) + err = convert_fuse_file_lock(&outarg.lk, fl); + + return err; +} + +static int fuse_setlk(struct file *file, struct file_lock *fl) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + struct fuse_req *req; + int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK; + pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0; + int err; + + /* Unlock on close is handled by the flush method */ + if (fl->fl_flags & FL_CLOSE) + return 0; + + req = fuse_get_req(fc); + if (IS_ERR(req)) + return PTR_ERR(req); + + fuse_lk_fill(req, file, fl, opcode, pid); + request_send(fc, req); + err = req->out.h.error; + fuse_put_request(fc, req); + return err; +} + +static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl) +{ + struct inode *inode = file->f_dentry->d_inode; + struct fuse_conn *fc = get_fuse_conn(inode); + int err; + + if (cmd == F_GETLK) { + if (fc->no_lock) { + if (!posix_test_lock(file, fl, fl)) + fl->fl_type = F_UNLCK; + err = 0; + } else + err = fuse_getlk(file, fl); + } else { + if (fc->no_lock) + err = posix_lock_file_wait(file, fl); + else + err = fuse_setlk(file, fl); + } + return err; +} + static const struct file_operations fuse_file_operations = { .llseek = generic_file_llseek, .read = generic_file_read, @@ -613,6 +743,7 @@ static const struct file_operations fuse_file_operations = { .flush = fuse_flush, .release = fuse_release, .fsync = fuse_fsync, + .lock = fuse_file_lock, .sendfile = generic_file_sendfile, }; @@ -624,6 +755,7 @@ static const struct file_operations fuse_direct_io_file_operations = { .flush = fuse_flush, .release = fuse_release, .fsync = fuse_fsync, + .lock = fuse_file_lock, /* no mmap and sendfile */ }; diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index ac12b01f4446..eb3166625ca9 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -190,6 +190,7 @@ struct fuse_req { struct fuse_init_in init_in; struct fuse_init_out init_out; struct fuse_read_in read_in; + struct fuse_lk_in lk_in; } misc; /** page vector */ @@ -307,6 +308,9 @@ struct fuse_conn { /** Is removexattr not implemented by fs? */ unsigned no_removexattr : 1; + /** Are file locking primitives not implemented by fs? */ + unsigned no_lock : 1; + /** Is access not implemented by fs? */ unsigned no_access : 1; diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 13a7e8ab7a78..412892905838 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -98,6 +98,14 @@ static void fuse_clear_inode(struct inode *inode) } } +static int fuse_remount_fs(struct super_block *sb, int *flags, char *data) +{ + if (*flags & MS_MANDLOCK) + return -EINVAL; + + return 0; +} + void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr) { if (S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size) @@ -409,6 +417,7 @@ static struct super_operations fuse_super_operations = { .destroy_inode = fuse_destroy_inode, .read_inode = fuse_read_inode, .clear_inode = fuse_clear_inode, + .remount_fs = fuse_remount_fs, .put_super = fuse_put_super, .umount_begin = fuse_umount_begin, .statfs = fuse_statfs, @@ -428,8 +437,12 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) ra_pages = arg->max_readahead / PAGE_CACHE_SIZE; if (arg->flags & FUSE_ASYNC_READ) fc->async_read = 1; - } else + if (!(arg->flags & FUSE_POSIX_LOCKS)) + fc->no_lock = 1; + } else { ra_pages = fc->max_read / PAGE_CACHE_SIZE; + fc->no_lock = 1; + } fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages); fc->minor = arg->minor; @@ -447,7 +460,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) arg->major = FUSE_KERNEL_VERSION; arg->minor = FUSE_KERNEL_MINOR_VERSION; arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE; - arg->flags |= FUSE_ASYNC_READ; + arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS; req->in.h.opcode = FUSE_INIT; req->in.numargs = 1; req->in.args[0].size = sizeof(*arg); @@ -479,6 +492,9 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent) struct fuse_req *init_req; int err; + if (sb->s_flags & MS_MANDLOCK) + return -EINVAL; + if (!parse_fuse_opt((char *) data, &d)) return -EINVAL; |