Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

avoid opening files when not needed in WASI, check for write permissions #449

Merged
merged 2 commits into from
May 15, 2019
Merged

avoid opening files when not needed in WASI, check for write permissions #449

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
b275273
avoid opening files when not needed in WASI, check for write permissions
May 15, 2019
83deae8
update changelog; clean up
May 15, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions CHANGELOG.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@ Blocks of changes will separated by version increments.

## **[Unreleased]**

- [#449](https://github.com/wasmerio/wasmer/pull/449) Fix bugs: opening host files in filestat and opening with write permissions unconditionally in path_open
- [#442](https://github.com/wasmerio/wasmer/pull/442) Misc. WASI FS fixes and implement readdir
- [#440](https://github.com/wasmerio/wasmer/pull/440) Fix type mismatch between `wasmer_instance_call` and `wasmer_export_func_*_arity` functions in the runtime C API.
- [#269](https://github.com/wasmerio/wasmer/pull/269) Add better runtime docs
Expand Down
13 changes: 13 additions & 0 deletions lib/wasi/src/state.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -451,3 +451,16 @@ pub struct WasiState<'a> {
pub args: &'a [Vec<u8>],
pub envs: &'a [Vec<u8>],
}

pub fn host_file_type_to_wasi_file_type(file_type: fs::FileType) -> __wasi_filetype_t {
// TODO: handle other file types
if file_type.is_dir() {
__WASI_FILETYPE_DIRECTORY
} else if file_type.is_file() {
__WASI_FILETYPE_REGULAR_FILE
} else if file_type.is_symlink() {
__WASI_FILETYPE_SYMBOLIC_LINK
} else {
__WASI_FILETYPE_UNKNOWN
}
}
74 changes: 19 additions & 55 deletions lib/wasi/src/syscalls/mod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,9 @@ pub mod windows;
use self::types::*;
use crate::{
ptr::{Array, WasmPtr},
state::{Fd, InodeVal, Kind, WasiFile, WasiState, MAX_SYMLINKS},
state::{
host_file_type_to_wasi_file_type, Fd, InodeVal, Kind, WasiFile, WasiState, MAX_SYMLINKS,
},
ExitCode,
};
use rand::{thread_rng, Rng};
Expand Down Expand Up @@ -796,19 +798,9 @@ pub fn fd_readdir(
d_next: cur_cookie,
d_ino: 0, // TODO: inode
d_namlen: namlen as u32,
d_type: {
let file_type = wasi_try!(entry.file_type().map_err(|_| __WASI_EIO));
// TODO: handle other file types
if file_type.is_dir() {
__WASI_FILETYPE_DIRECTORY
} else if file_type.is_file() {
__WASI_FILETYPE_REGULAR_FILE
} else if file_type.is_symlink() {
__WASI_FILETYPE_SYMBOLIC_LINK
} else {
__WASI_FILETYPE_UNKNOWN
}
},
d_type: host_file_type_to_wasi_file_type(wasi_try!(entry
.file_type()
.map_err(|_| __WASI_EIO))),
};
let dirent_bytes = dirent_to_le_bytes(&dirent);
let upper_limit = std::cmp::min(
Expand Down Expand Up @@ -1219,64 +1211,31 @@ pub fn path_filestat_get(
}
}

let final_inode = match &state.fs.inodes[inode].kind {
let stat = match &state.fs.inodes[inode].kind {
Kind::Dir { path, entries, .. } => {
// TODO: fail earlier if size 0
// read it from internal data structures if we can
let last_segment = path_vec.last().unwrap();
cumulative_path.push(last_segment);

if entries.contains_key(last_segment) {
entries[last_segment]
state.fs.inodes[entries[last_segment]].stat
} else {
// lazily load it if we can
// otherwise read it from the host FS
if !cumulative_path.exists() {
return __WASI_ENOENT;
}
let final_path_metadata =
wasi_try!(cumulative_path.metadata().map_err(|_| __WASI_EIO));
let new_inode = if final_path_metadata.is_dir() {
debug!("Opening host directory {:#?}", &cumulative_path);
state.fs.inodes.insert(InodeVal {
stat: __wasi_filestat_t::default(),
is_preopened: false, // is this correct?
name: last_segment.clone(),
kind: Kind::Dir {
parent: Some(inode),
path: std::path::PathBuf::from(&last_segment),
entries: Default::default(),
},
})
} else {
debug!("Opening host file {:#?}", &cumulative_path);
let real_open_file = wasi_try!(std::fs::OpenOptions::new()
.read(true)
.write(true)
.open(&cumulative_path)
.map_err(|_| __WASI_ENOENT));

state.fs.inodes.insert(InodeVal {
stat: __wasi_filestat_t::default(),
is_preopened: false, // is this correct?
name: last_segment.clone(),
kind: Kind::File {
handle: WasiFile::HostFile(real_open_file),
},
})
};
// reborrow to insert entry
if let Kind::Dir { entries, .. } = &mut state.fs.inodes[inode].kind {
entries.insert(last_segment.clone(), new_inode);
__wasi_filestat_t {
st_filetype: host_file_type_to_wasi_file_type(final_path_metadata.file_type()),
..Default::default()
}
new_inode
}
}
_ => {
return __WASI_ENOTDIR;
}
};

let stat = state.fs.inodes[final_inode].stat;

buf_cell.set(stat);

__WASI_ESUCCESS
Expand Down Expand Up @@ -1540,7 +1499,12 @@ pub fn path_open(
// file is not a dir
let real_opened_file = {
let mut open_options = std::fs::OpenOptions::new();
let open_options = open_options.read(true).write(true);
let open_options = open_options.read(true);
let open_options = if fs_rights_base & __WASI_RIGHT_FD_WRITE != 0 {
open_options.write(true)
} else {
open_options
};
let open_options = if o_flags & __WASI_O_CREAT != 0 {
debug!(
"File {:?} may be created when opened if it does not exist",
Expand Down