| // SPDX-License-Identifier: GPL-2.0 |
| #include <linux/kernel.h> |
| #include <linux/errno.h> |
| #include <linux/fs.h> |
| #include <linux/file.h> |
| #include <linux/fdtable.h> |
| #include <linux/fsnotify.h> |
| #include <linux/namei.h> |
| #include <linux/io_uring.h> |
| |
| #include <uapi/linux/io_uring.h> |
| |
| #include "../fs/internal.h" |
| |
| #include "io_uring.h" |
| #include "rsrc.h" |
| #include "openclose.h" |
| |
| struct io_open { |
| struct file *file; |
| int dfd; |
| u32 file_slot; |
| struct filename *filename; |
| struct open_how how; |
| unsigned long nofile; |
| }; |
| |
| struct io_close { |
| struct file *file; |
| int fd; |
| u32 file_slot; |
| }; |
| |
| static bool io_openat_force_async(struct io_open *open) |
| { |
| /* |
| * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open, |
| * it'll always -EAGAIN |
| */ |
| return open->how.flags & (O_TRUNC | O_CREAT | O_TMPFILE); |
| } |
| |
| static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| { |
| struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
| const char __user *fname; |
| int ret; |
| |
| if (unlikely(sqe->buf_index)) |
| return -EINVAL; |
| if (unlikely(req->flags & REQ_F_FIXED_FILE)) |
| return -EBADF; |
| |
| /* open.how should be already initialised */ |
| if (!(open->how.flags & O_PATH) && force_o_largefile()) |
| open->how.flags |= O_LARGEFILE; |
| |
| open->dfd = READ_ONCE(sqe->fd); |
| fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); |
| open->filename = getname(fname); |
| if (IS_ERR(open->filename)) { |
| ret = PTR_ERR(open->filename); |
| open->filename = NULL; |
| return ret; |
| } |
| |
| open->file_slot = READ_ONCE(sqe->file_index); |
| if (open->file_slot && (open->how.flags & O_CLOEXEC)) |
| return -EINVAL; |
| |
| open->nofile = rlimit(RLIMIT_NOFILE); |
| req->flags |= REQ_F_NEED_CLEANUP; |
| if (io_openat_force_async(open)) |
| req->flags |= REQ_F_FORCE_ASYNC; |
| return 0; |
| } |
| |
| int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| { |
| struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
| u64 mode = READ_ONCE(sqe->len); |
| u64 flags = READ_ONCE(sqe->open_flags); |
| |
| open->how = build_open_how(flags, mode); |
| return __io_openat_prep(req, sqe); |
| } |
| |
| int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| { |
| struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
| struct open_how __user *how; |
| size_t len; |
| int ret; |
| |
| how = u64_to_user_ptr(READ_ONCE(sqe->addr2)); |
| len = READ_ONCE(sqe->len); |
| if (len < OPEN_HOW_SIZE_VER0) |
| return -EINVAL; |
| |
| ret = copy_struct_from_user(&open->how, sizeof(open->how), how, len); |
| if (ret) |
| return ret; |
| |
| return __io_openat_prep(req, sqe); |
| } |
| |
| int io_openat2(struct io_kiocb *req, unsigned int issue_flags) |
| { |
| struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
| struct open_flags op; |
| struct file *file; |
| bool resolve_nonblock, nonblock_set; |
| bool fixed = !!open->file_slot; |
| int ret; |
| |
| ret = build_open_flags(&open->how, &op); |
| if (ret) |
| goto err; |
| nonblock_set = op.open_flag & O_NONBLOCK; |
| resolve_nonblock = open->how.resolve & RESOLVE_CACHED; |
| if (issue_flags & IO_URING_F_NONBLOCK) { |
| WARN_ON_ONCE(io_openat_force_async(open)); |
| op.lookup_flags |= LOOKUP_CACHED; |
| op.open_flag |= O_NONBLOCK; |
| } |
| |
| if (!fixed) { |
| ret = __get_unused_fd_flags(open->how.flags, open->nofile); |
| if (ret < 0) |
| goto err; |
| } |
| |
| file = do_filp_open(open->dfd, open->filename, &op); |
| if (IS_ERR(file)) { |
| /* |
| * We could hang on to this 'fd' on retrying, but seems like |
| * marginal gain for something that is now known to be a slower |
| * path. So just put it, and we'll get a new one when we retry. |
| */ |
| if (!fixed) |
| put_unused_fd(ret); |
| |
| ret = PTR_ERR(file); |
| /* only retry if RESOLVE_CACHED wasn't already set by application */ |
| if (ret == -EAGAIN && |
| (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK))) |
| return -EAGAIN; |
| goto err; |
| } |
| |
| if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set) |
| file->f_flags &= ~O_NONBLOCK; |
| |
| if (!fixed) |
| fd_install(ret, file); |
| else |
| ret = io_fixed_fd_install(req, issue_flags, file, |
| open->file_slot); |
| err: |
| putname(open->filename); |
| req->flags &= ~REQ_F_NEED_CLEANUP; |
| if (ret < 0) |
| req_set_fail(req); |
| io_req_set_res(req, ret, 0); |
| return IOU_OK; |
| } |
| |
| int io_openat(struct io_kiocb *req, unsigned int issue_flags) |
| { |
| return io_openat2(req, issue_flags); |
| } |
| |
| void io_open_cleanup(struct io_kiocb *req) |
| { |
| struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
| |
| if (open->filename) |
| putname(open->filename); |
| } |
| |
| int __io_close_fixed(struct io_ring_ctx *ctx, unsigned int issue_flags, |
| unsigned int offset) |
| { |
| int ret; |
| |
| io_ring_submit_lock(ctx, issue_flags); |
| ret = io_fixed_fd_remove(ctx, offset); |
| io_ring_submit_unlock(ctx, issue_flags); |
| |
| return ret; |
| } |
| |
| static inline int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags) |
| { |
| struct io_close *close = io_kiocb_to_cmd(req, struct io_close); |
| |
| return __io_close_fixed(req->ctx, issue_flags, close->file_slot - 1); |
| } |
| |
| int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| { |
| struct io_close *close = io_kiocb_to_cmd(req, struct io_close); |
| |
| if (sqe->off || sqe->addr || sqe->len || sqe->rw_flags || sqe->buf_index) |
| return -EINVAL; |
| if (req->flags & REQ_F_FIXED_FILE) |
| return -EBADF; |
| |
| close->fd = READ_ONCE(sqe->fd); |
| close->file_slot = READ_ONCE(sqe->file_index); |
| if (close->file_slot && close->fd) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| int io_close(struct io_kiocb *req, unsigned int issue_flags) |
| { |
| struct files_struct *files = current->files; |
| struct io_close *close = io_kiocb_to_cmd(req, struct io_close); |
| struct fdtable *fdt; |
| struct file *file; |
| int ret = -EBADF; |
| |
| if (close->file_slot) { |
| ret = io_close_fixed(req, issue_flags); |
| goto err; |
| } |
| |
| spin_lock(&files->file_lock); |
| fdt = files_fdtable(files); |
| if (close->fd >= fdt->max_fds) { |
| spin_unlock(&files->file_lock); |
| goto err; |
| } |
| file = rcu_dereference_protected(fdt->fd[close->fd], |
| lockdep_is_held(&files->file_lock)); |
| if (!file || io_is_uring_fops(file)) { |
| spin_unlock(&files->file_lock); |
| goto err; |
| } |
| |
| /* if the file has a flush method, be safe and punt to async */ |
| if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) { |
| spin_unlock(&files->file_lock); |
| return -EAGAIN; |
| } |
| |
| file = __close_fd_get_file(close->fd); |
| spin_unlock(&files->file_lock); |
| if (!file) |
| goto err; |
| |
| /* No ->flush() or already async, safely close from here */ |
| ret = filp_close(file, current->files); |
| err: |
| if (ret < 0) |
| req_set_fail(req); |
| io_req_set_res(req, ret, 0); |
| return IOU_OK; |
| } |