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-rw-r--r--vendor/memmap2/src/lib.rs149
-rw-r--r--vendor/memmap2/src/unix.rs42
-rw-r--r--vendor/memmap2/src/windows.rs43
3 files changed, 167 insertions, 67 deletions
diff --git a/vendor/memmap2/src/lib.rs b/vendor/memmap2/src/lib.rs
index b90d1bcf6..0b92ea0e1 100644
--- a/vendor/memmap2/src/lib.rs
+++ b/vendor/memmap2/src/lib.rs
@@ -51,13 +51,14 @@ use std::fmt;
#[cfg(not(any(unix, windows)))]
use std::fs::File;
use std::io::{Error, ErrorKind, Result};
+use std::isize;
+use std::mem;
use std::ops::{Deref, DerefMut};
#[cfg(unix)]
use std::os::unix::io::{AsRawFd, RawFd};
#[cfg(windows)]
use std::os::windows::io::{AsRawHandle, RawHandle};
use std::slice;
-use std::usize;
#[cfg(not(any(unix, windows)))]
pub struct MmapRawDescriptor<'a>(&'a File);
@@ -237,15 +238,20 @@ impl MmapOptions {
}
let len = file_len - self.offset;
- // This check it not relevant on 64bit targets, because usize == u64
- #[cfg(not(target_pointer_width = "64"))]
- {
- if len > (usize::MAX as u64) {
- return Err(Error::new(
- ErrorKind::InvalidData,
- "memory map length overflows usize",
- ));
- }
+ // Rust's slice cannot be larger than isize::MAX.
+ // See https://doc.rust-lang.org/std/slice/fn.from_raw_parts.html
+ //
+ // This is not a problem on 64-bit targets, but on 32-bit one
+ // having a file or an anonymous mapping larger than 2GB is quite normal
+ // and we have to prevent it.
+ //
+ // The code below is essentially the same as in Rust's std:
+ // https://github.com/rust-lang/rust/blob/db78ab70a88a0a5e89031d7ee4eccec835dcdbde/library/alloc/src/raw_vec.rs#L495
+ if mem::size_of::<usize>() < 8 && len > isize::MAX as u64 {
+ return Err(Error::new(
+ ErrorKind::InvalidData,
+ "memory map length overflows isize",
+ ));
}
Ok(len as usize)
@@ -457,14 +463,26 @@ impl MmapOptions {
/// Creates an anonymous memory map.
///
- /// Note: the memory map length must be configured to be greater than 0 before creating an
- /// anonymous memory map using `MmapOptions::len()`.
+ /// The memory map length should be configured using [`MmapOptions::len()`]
+ /// before creating an anonymous memory map, otherwise a zero-length mapping
+ /// will be crated.
///
/// # Errors
///
- /// This method returns an error when the underlying system call fails.
+ /// This method returns an error when the underlying system call fails or
+ /// when `len > isize::MAX`.
pub fn map_anon(&self) -> Result<MmapMut> {
- MmapInner::map_anon(self.len.unwrap_or(0), self.stack).map(|inner| MmapMut { inner })
+ let len = self.len.unwrap_or(0);
+
+ // See get_len() for details.
+ if mem::size_of::<usize>() < 8 && len > isize::MAX as usize {
+ return Err(Error::new(
+ ErrorKind::InvalidData,
+ "memory map length overflows isize",
+ ));
+ }
+
+ MmapInner::map_anon(len, self.stack).map(|inner| MmapMut { inner })
}
/// Creates a raw memory map.
@@ -611,6 +629,22 @@ impl Mmap {
pub fn advise(&self, advice: Advice) -> Result<()> {
self.inner.advise(advice)
}
+
+ /// Lock the whole memory map into RAM. Only supported on Unix.
+ ///
+ /// See [mlock()](https://man7.org/linux/man-pages/man2/mlock.2.html) map page.
+ #[cfg(unix)]
+ pub fn lock(&mut self) -> Result<()> {
+ self.inner.lock()
+ }
+
+ /// Unlock the whole memory map. Only supported on Unix.
+ ///
+ /// See [munlock()](https://man7.org/linux/man-pages/man2/munlock.2.html) map page.
+ #[cfg(unix)]
+ pub fn unlock(&mut self) -> Result<()> {
+ self.inner.unlock()
+ }
}
#[cfg(feature = "stable_deref_trait")]
@@ -856,7 +890,8 @@ impl MmapMut {
///
/// # Errors
///
- /// This method returns an error when the underlying system call fails.
+ /// This method returns an error when the underlying system call fails or
+ /// when `len > isize::MAX`.
pub fn map_anon(length: usize) -> Result<MmapMut> {
MmapOptions::new().len(length).map_anon()
}
@@ -987,6 +1022,22 @@ impl MmapMut {
pub fn advise(&self, advice: Advice) -> Result<()> {
self.inner.advise(advice)
}
+
+ /// Lock the whole memory map into RAM. Only supported on Unix.
+ ///
+ /// See [mlock()](https://man7.org/linux/man-pages/man2/mlock.2.html) map page.
+ #[cfg(unix)]
+ pub fn lock(&mut self) -> Result<()> {
+ self.inner.lock()
+ }
+
+ /// Unlock the whole memory map. Only supported on Unix.
+ ///
+ /// See [munlock()](https://man7.org/linux/man-pages/man2/munlock.2.html) map page.
+ #[cfg(unix)]
+ pub fn unlock(&mut self) -> Result<()> {
+ self.inner.unlock()
+ }
}
#[cfg(feature = "stable_deref_trait")]
@@ -1037,7 +1088,7 @@ mod test {
#[cfg(unix)]
use crate::advice::Advice;
- use std::fs::OpenOptions;
+ use std::fs::{self, OpenOptions};
use std::io::{Read, Write};
#[cfg(unix)]
use std::os::unix::io::AsRawFd;
@@ -1158,6 +1209,17 @@ mod test {
}
#[test]
+ #[cfg(target_pointer_width = "32")]
+ fn map_anon_len_overflow() {
+ let res = MmapMut::map_anon(0x80000000);
+
+ assert_eq!(
+ res.unwrap_err().to_string(),
+ "memory map length overflows isize"
+ );
+ }
+
+ #[test]
fn file_write() {
let tempdir = tempfile::tempdir().unwrap();
let path = tempdir.path().join("mmap");
@@ -1333,7 +1395,6 @@ mod test {
#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
fn jit_x86(mut mmap: MmapMut) {
- use std::mem;
mmap[0] = 0xB8; // mov eax, 0xAB
mmap[1] = 0xAB;
mmap[2] = 0x00;
@@ -1343,7 +1404,7 @@ mod test {
let mmap = mmap.make_exec().expect("make_exec");
- let jitfn: extern "C" fn() -> u8 = unsafe { mem::transmute(mmap.as_ptr()) };
+ let jitfn: extern "C" fn() -> u8 = unsafe { std::mem::transmute(mmap.as_ptr()) };
assert_eq!(jitfn(), 0xab);
}
@@ -1557,4 +1618,56 @@ mod test {
// read values back
assert_eq!(&incr[..], &mmap[..]);
}
+
+ /// Returns true if a non-zero amount of memory is locked.
+ #[cfg(target_os = "linux")]
+ fn is_locked() -> bool {
+ let status = &fs::read_to_string("/proc/self/status")
+ .expect("/proc/self/status should be available");
+ for line in status.lines() {
+ if line.starts_with("VmLck:") {
+ let numbers = line.replace(|c: char| !c.is_ascii_digit(), "");
+ return numbers != "0";
+ }
+ }
+ panic!("cannot get VmLck information")
+ }
+
+ #[test]
+ #[cfg(unix)]
+ fn lock() {
+ let tempdir = tempfile::tempdir().unwrap();
+ let path = tempdir.path().join("mmap_lock");
+
+ let file = OpenOptions::new()
+ .read(true)
+ .write(true)
+ .create(true)
+ .open(&path)
+ .unwrap();
+ file.set_len(128).unwrap();
+
+ let mut mmap = unsafe { Mmap::map(&file).unwrap() };
+ #[cfg(target_os = "linux")]
+ assert!(!is_locked());
+
+ mmap.lock().expect("mmap lock should be supported on unix");
+ #[cfg(target_os = "linux")]
+ assert!(is_locked());
+
+ mmap.lock()
+ .expect("mmap lock again should not cause problems");
+ #[cfg(target_os = "linux")]
+ assert!(is_locked());
+
+ mmap.unlock()
+ .expect("mmap unlock should be supported on unix");
+ #[cfg(target_os = "linux")]
+ assert!(!is_locked());
+
+ mmap.unlock()
+ .expect("mmap unlock again should not cause problems");
+ #[cfg(target_os = "linux")]
+ assert!(!is_locked());
+ }
}
diff --git a/vendor/memmap2/src/unix.rs b/vendor/memmap2/src/unix.rs
index cd3dcdbce..158d78c1f 100644
--- a/vendor/memmap2/src/unix.rs
+++ b/vendor/memmap2/src/unix.rs
@@ -1,7 +1,8 @@
extern crate libc;
-use std::mem::MaybeUninit;
-use std::os::unix::io::RawFd;
+use std::fs::File;
+use std::mem::ManuallyDrop;
+use std::os::unix::io::{FromRawFd, RawFd};
use std::sync::atomic::{AtomicUsize, Ordering};
use std::{io, ptr};
@@ -248,6 +249,26 @@ impl MmapInner {
}
}
}
+
+ pub fn lock(&self) -> io::Result<()> {
+ unsafe {
+ if libc::mlock(self.ptr, self.len) != 0 {
+ Err(io::Error::last_os_error())
+ } else {
+ Ok(())
+ }
+ }
+ }
+
+ pub fn unlock(&self) -> io::Result<()> {
+ unsafe {
+ if libc::munlock(self.ptr, self.len) != 0 {
+ Err(io::Error::last_os_error())
+ } else {
+ Ok(())
+ }
+ }
+ }
}
impl Drop for MmapInner {
@@ -284,19 +305,10 @@ fn page_size() -> usize {
}
pub fn file_len(file: RawFd) -> io::Result<u64> {
- #[cfg(not(any(target_os = "linux", target_os = "emscripten", target_os = "l4re")))]
- use libc::{fstat, stat};
- #[cfg(any(target_os = "linux", target_os = "emscripten", target_os = "l4re"))]
- use libc::{fstat64 as fstat, stat64 as stat};
-
+ // SAFETY: We must not close the passed-in fd by dropping the File we create,
+ // we ensure this by immediately wrapping it in a ManuallyDrop.
unsafe {
- let mut stat = MaybeUninit::<stat>::uninit();
-
- let result = fstat(file, stat.as_mut_ptr());
- if result == 0 {
- Ok(stat.assume_init().st_size as u64)
- } else {
- Err(io::Error::last_os_error())
- }
+ let file = ManuallyDrop::new(File::from_raw_fd(file));
+ Ok(file.metadata()?.len())
}
}
diff --git a/vendor/memmap2/src/windows.rs b/vendor/memmap2/src/windows.rs
index b3b8c620a..d580995e6 100644
--- a/vendor/memmap2/src/windows.rs
+++ b/vendor/memmap2/src/windows.rs
@@ -1,8 +1,10 @@
#![allow(non_camel_case_types)]
#![allow(non_snake_case)]
+use std::fs::File;
+use std::mem::ManuallyDrop;
use std::os::raw::c_void;
-use std::os::windows::io::RawHandle;
+use std::os::windows::io::{FromRawHandle, RawHandle};
use std::{io, mem, ptr};
type BOOL = i32;
@@ -82,22 +84,6 @@ pub struct FILETIME {
pub dwHighDateTime: DWORD,
}
-#[repr(C)]
-struct BY_HANDLE_FILE_INFORMATION {
- dwFileAttributes: DWORD,
- ftCreationTime: FILETIME,
- ftLastAccessTime: FILETIME,
- ftLastWriteTime: FILETIME,
- dwVolumeSerialNumber: DWORD,
- nFileSizeHigh: DWORD,
- nFileSizeLow: DWORD,
- nNumberOfLinks: DWORD,
- nFileIndexHigh: DWORD,
- nFileIndexLow: DWORD,
-}
-
-type LPBY_HANDLE_FILE_INFORMATION = *mut BY_HANDLE_FILE_INFORMATION;
-
extern "system" {
fn GetCurrentProcess() -> HANDLE;
@@ -124,11 +110,6 @@ extern "system" {
fn FlushFileBuffers(hFile: HANDLE) -> BOOL;
- fn GetFileInformationByHandle(
- hFile: HANDLE,
- lpFileInformation: LPBY_HANDLE_FILE_INFORMATION,
- ) -> BOOL;
-
fn FlushViewOfFile(lpBaseAddress: LPCVOID, dwNumberOfBytesToFlush: SIZE_T) -> BOOL;
fn UnmapViewOfFile(lpBaseAddress: LPCVOID) -> BOOL;
@@ -526,16 +507,10 @@ fn allocation_granularity() -> usize {
}
pub fn file_len(handle: RawHandle) -> io::Result<u64> {
- let info = unsafe {
- let mut info = mem::MaybeUninit::<BY_HANDLE_FILE_INFORMATION>::uninit();
-
- let ok = GetFileInformationByHandle(handle, info.as_mut_ptr());
- if ok == 0 {
- return Err(io::Error::last_os_error());
- }
-
- info.assume_init()
- };
-
- Ok((info.nFileSizeHigh as u64) << 32 | info.nFileSizeLow as u64)
+ // SAFETY: We must not close the passed-in fd by dropping the File we create,
+ // we ensure this by immediately wrapping it in a ManuallyDrop.
+ unsafe {
+ let file = ManuallyDrop::new(File::from_raw_handle(handle));
+ Ok(file.metadata()?.len())
+ }
}