From 276112188e477b79a4487ea2424946c2917c9423 Mon Sep 17 00:00:00 2001
From: Jonathan Klimt <jonathan.klimt@eonerc.rwth-aachen.de>
Date: Wed, 31 Jan 2024 17:50:27 +0100
Subject: [PATCH] Fixed incorrect type of the data buffers in the two file
 system hypercalls. Note: I did not increase the interface version, as there
 are no kernels out there that have used the incorrect type and uhyve has
 always treated it the way it is now.

---
 src/hypercall.rs                  | 16 ++++++++--------
 uhyve-interface/src/parameters.rs |  6 +++---
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/src/hypercall.rs b/src/hypercall.rs
index 05d5eaae..47921ec6 100644
--- a/src/hypercall.rs
+++ b/src/hypercall.rs
@@ -1,13 +1,15 @@
 use std::{
 	ffi::{OsStr, OsString},
-	io,
-	io::Write,
+	io::{self, Error, ErrorKind, Write},
 	os::unix::ffi::OsStrExt,
 };
 
 use uhyve_interface::{parameters::*, GuestPhysAddr, Hypercall, HypercallAddress, MAX_ARGC_ENVC};
 
-use crate::mem::MmapMemory;
+use crate::{
+	mem::{MemoryError, MmapMemory},
+	virt_to_phys,
+};
 
 /// `addr` is the address of the hypercall parameter in the guest's memory space. `data` is the
 /// parameter that was send to that address by the guest.
@@ -99,7 +101,8 @@ pub fn read(mem: &MmapMemory, sysread: &mut ReadPrams) {
 	unsafe {
 		let bytes_read = libc::read(
 			sysread.fd,
-			mem.host_address(sysread.buf).unwrap() as *mut libc::c_void,
+			mem.host_address(virt_to_phys(sysread.buf, mem).unwrap())
+				.unwrap() as *mut libc::c_void,
 			sysread.len,
 		);
 		if bytes_read >= 0 {
@@ -115,12 +118,9 @@ pub fn write(mem: &MmapMemory, syswrite: &WriteParams) -> io::Result<()> {
 	let mut bytes_written: usize = 0;
 	while bytes_written != syswrite.len {
 		unsafe {
-			use std::io::{Error, ErrorKind};
-
-			use crate::mem::MemoryError;
 			let step = libc::write(
 				syswrite.fd,
-				mem.host_address(syswrite.buf + bytes_written)
+				mem.host_address(virt_to_phys(syswrite.buf + bytes_written as u64, mem).unwrap())
 					.map_err(|e| match e {
 						MemoryError::BoundsViolation => {
 							unreachable!("Bounds violation after host_address function")
diff --git a/uhyve-interface/src/parameters.rs b/uhyve-interface/src/parameters.rs
index 1d279b68..2f3887fe 100644
--- a/uhyve-interface/src/parameters.rs
+++ b/uhyve-interface/src/parameters.rs
@@ -2,7 +2,7 @@
 
 use std::path::Path;
 
-use crate::{GuestPhysAddr, MAX_ARGC_ENVC};
+use crate::{GuestPhysAddr, GuestVirtAddr, MAX_ARGC_ENVC};
 
 /// Parameters for a [`Cmdsize`](crate::Hypercall::Cmdsize) hypercall which provides the lengths of the items in the argument end environment vector.
 #[repr(C, packed)]
@@ -84,7 +84,7 @@ pub struct WriteParams {
 	/// File descriptor of the file.
 	pub fd: i32,
 	/// Buffer to be written into the file.
-	pub buf: GuestPhysAddr,
+	pub buf: GuestVirtAddr,
 	/// Number of bytes in the buffer to be written.
 	pub len: usize,
 }
@@ -96,7 +96,7 @@ pub struct ReadPrams {
 	/// File descriptor of the file.
 	pub fd: i32,
 	/// Buffer to read the file into.
-	pub buf: GuestPhysAddr,
+	pub buf: GuestVirtAddr,
 	/// Number of bytes to read into the buffer.
 	pub len: usize,
 	/// Number of bytes read on success. `-1` on failure.