diff --git a/Cargo.lock b/Cargo.lock
index 8b8a05f9..d471cf8c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,6 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "acpi"
@@ -127,9 +127,9 @@ dependencies = [
 
 [[package]]
 name = "defmt"
-version = "0.3.5"
+version = "0.3.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a8a2d011b2fee29fb7d659b83c43fce9a2cb4df453e16d441a51448e448f3f98"
+checksum = "86f6162c53f659f65d00619fe31f14556a6e9f8752ccc4a41bd177ffcf3d6130"
 dependencies = [
  "bitflags 1.3.2",
  "defmt-macros",
@@ -137,22 +137,22 @@ dependencies = [
 
 [[package]]
 name = "defmt-macros"
-version = "0.3.6"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "54f0216f6c5acb5ae1a47050a6645024e6edafc2ee32d421955eccfef12ef92e"
+checksum = "9d135dd939bad62d7490b0002602d35b358dce5fd9233a709d3c1ef467d4bde6"
 dependencies = [
  "defmt-parser",
- "proc-macro-error",
+ "proc-macro-error2",
  "proc-macro2",
  "quote",
- "syn 2.0.41",
+ "syn 2.0.90",
 ]
 
 [[package]]
 name = "defmt-parser"
-version = "0.3.3"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "269924c02afd7f94bc4cecbfa5c379f6ffcf9766b3408fe63d22c728654eccd0"
+checksum = "3983b127f13995e68c1e29071e5d115cd96f215ccb5e6812e3728cd6f92653b3"
 dependencies = [
  "thiserror",
 ]
@@ -416,27 +416,25 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
 
 [[package]]
-name = "proc-macro-error"
-version = "1.0.4"
+name = "proc-macro-error-attr2"
+version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da25490ff9892aab3fcf7c36f08cfb902dd3e71ca0f9f9517bea02a73a5ce38c"
+checksum = "96de42df36bb9bba5542fe9f1a054b8cc87e172759a1868aa05c1f3acc89dfc5"
 dependencies = [
- "proc-macro-error-attr",
  "proc-macro2",
  "quote",
- "syn 1.0.109",
- "version_check",
 ]
 
 [[package]]
-name = "proc-macro-error-attr"
-version = "1.0.4"
+name = "proc-macro-error2"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a1be40180e52ecc98ad80b184934baf3d0d29f979574e439af5a55274b35f869"
+checksum = "11ec05c52be0a07b08061f7dd003e7d7092e0472bc731b4af7bb1ef876109802"
 dependencies = [
+ "proc-macro-error-attr2",
  "proc-macro2",
  "quote",
- "version_check",
+ "syn 2.0.90",
 ]
 
 [[package]]
@@ -447,18 +445,18 @@ checksum = "dc375e1527247fe1a97d8b7156678dfe7c1af2fc075c9a4db3690ecd2a148068"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.70"
+version = "1.0.92"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "39278fbbf5fb4f646ce651690877f89d1c5811a3d4acb27700c1cb3cdb78fd3b"
+checksum = "37d3544b3f2748c54e147655edb5025752e2303145b5aefb3c3ea2c78b973bb0"
 dependencies = [
  "unicode-ident",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.33"
+version = "1.0.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5267fca4496028628a95160fc423a33e8b2e6af8a5302579e322e4b520293cae"
+checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
 dependencies = [
  "proc-macro2",
 ]
@@ -581,9 +579,9 @@ dependencies = [
 
 [[package]]
 name = "smoltcp"
-version = "0.11.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a1a996951e50b5971a2c8c0fa05a381480d70a933064245c4a223ddc87ccc97"
+checksum = "dad095989c1533c1c266d9b1e8d70a1329dd3723c3edac6d03bbd67e7bf6f4bb"
 dependencies = [
  "bitflags 1.3.2",
  "byteorder",
@@ -645,9 +643,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.41"
+version = "2.0.90"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "44c8b28c477cc3bf0e7966561e3460130e1255f7a1cf71931075f1c5e7a7e269"
+checksum = "919d3b74a5dd0ccd15aeb8f93e7006bd9e14c295087c9896a110f490752bcf31"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -662,22 +660,22 @@ checksum = "55937e1799185b12863d447f42597ed69d9928686b8d88a1df17376a097d8369"
 
 [[package]]
 name = "thiserror"
-version = "1.0.51"
+version = "2.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f11c217e1416d6f036b870f14e0413d480dbf28edbee1f877abaf0206af43bb7"
+checksum = "2f49a1853cf82743e3b7950f77e0f4d622ca36cf4317cba00c767838bac8d490"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.51"
+version = "2.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "01742297787513b79cf8e29d1056ede1313e2420b7b3b15d0a768b4921f549df"
+checksum = "8381894bb3efe0c4acac3ded651301ceee58a15d47c2e34885ed1908ad667061"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.41",
+ "syn 2.0.90",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 4e52496c..5f0c7490 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -36,7 +36,7 @@ rand = { version = "0.8.5", default-features = false }
 rand_hc = "0.3.1"
 raw-cpuid = "11.2.0"
 sha2 = { version = "0.10.8", default-features = false, features = ["force-soft"] }
-smoltcp = { version = "0.11.0", default-features = false, features = ["alloc", "medium-ethernet", "socket-tcp", "socket-udp", "socket-dhcpv4", "proto-ipv4", "proto-dhcpv4"] }
+smoltcp = { version = "0.12.0", default-features = false, features = ["alloc", "medium-ethernet", "socket-tcp", "socket-udp", "socket-dhcpv4", "proto-ipv4", "proto-dhcpv4"] }
 spin = "0.9.8"
 time = { version = "0.2.27", default-features = false }
 geodate = { version = "0.5.0", default-features = false }
diff --git a/src/api/syscall.rs b/src/api/syscall.rs
index 9241a569..4d7601a7 100644
--- a/src/api/syscall.rs
+++ b/src/api/syscall.rs
@@ -4,6 +4,7 @@ use crate::sys::fs::{FileInfo, FileType};
 use crate::sys::syscall::number::*;
 use crate::syscall;
 
+use core::convert::TryInto;
 use core::convert::TryFrom;
 use core::sync::atomic::{fence, Ordering};
 use smoltcp::wire::{IpAddress, Ipv4Address};
@@ -127,7 +128,9 @@ pub fn poll(list: &[(usize, IO)]) -> Option<(usize, IO)> {
 }
 
 pub fn connect(handle: usize, addr: IpAddress, port: u16) -> Result<(), ()> {
-    let buf = addr.as_bytes();
+    let IpAddress::Ipv4(addr) = addr; // Only IPv4 is supported
+    let tmp = addr.octets();
+    let buf = tmp.as_slice();
     let ptr = buf.as_ptr() as usize;
     let len = buf.len();
     let res = unsafe { syscall!(CONNECT, handle, ptr, len, port) } as isize;
@@ -148,16 +151,18 @@ pub fn listen(handle: usize, port: u16) -> Result<(), ()> {
 }
 
 pub fn accept(handle: usize) -> Result<IpAddress, ()> {
-    let addr = IpAddress::v4(0, 0, 0, 0);
-    let buf = addr.as_bytes();
+    let addr = Ipv4Address::new(0, 0, 0, 0);
+    let tmp = addr.octets();
+    let buf = tmp.as_slice();
     let ptr = buf.as_ptr() as usize;
     let len = buf.len();
     let res = unsafe { syscall!(ACCEPT, handle, ptr, len) } as isize;
     if res >= 0 {
-        Ok(IpAddress::from(Ipv4Address::from_bytes(buf)))
-    } else {
-        Err(())
+        if let Ok(buf) = buf.try_into() {
+            return Ok(IpAddress::from(Ipv4Address::from_octets(buf)));
+        }
     }
+    Err(())
 }
 
 pub fn alloc(size: usize, align: usize) -> *mut u8 {
diff --git a/src/lib.rs b/src/lib.rs
index 62b48321..46b4dced 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,10 +1,11 @@
 #![no_std]
 #![cfg_attr(test, no_main)]
-#![feature(vec_pop_if)]
 #![feature(abi_x86_interrupt)]
 #![feature(alloc_error_handler)]
-#![feature(naked_functions)]
 #![feature(custom_test_frameworks)]
+#![feature(ip_from)]
+#![feature(naked_functions)]
+#![feature(vec_pop_if)]
 #![test_runner(crate::test_runner)]
 #![reexport_test_harness_main = "test_main"]
 
diff --git a/src/sys/net/mod.rs b/src/sys/net/mod.rs
index 00cc6854..439a4981 100644
--- a/src/sys/net/mod.rs
+++ b/src/sys/net/mod.rs
@@ -141,11 +141,11 @@ pub struct RxToken {
 }
 
 impl smoltcp::phy::RxToken for RxToken {
-    fn consume<R, F>(mut self, f: F) -> R
+    fn consume<R, F>(self, f: F) -> R
     where
-        F: FnOnce(&mut [u8]) -> R,
+        F: FnOnce(&[u8]) -> R,
     {
-        f(&mut self.buffer)
+        f(&self.buffer)
     }
 }
 
diff --git a/src/sys/syscall/mod.rs b/src/sys/syscall/mod.rs
index 8d0286ef..452cc6fb 100644
--- a/src/sys/syscall/mod.rs
+++ b/src/sys/syscall/mod.rs
@@ -6,6 +6,7 @@ use crate::sys;
 use crate::sys::fs::FileInfo;
 
 use core::arch::asm;
+use core::convert::TryInto;
 use smoltcp::wire::IpAddress;
 use smoltcp::wire::Ipv4Address;
 
@@ -104,9 +105,13 @@ pub fn dispatcher(
             let ptr = sys::process::ptr_from_addr(arg2 as u64);
             let len = arg3;
             let buf = unsafe { core::slice::from_raw_parts(ptr, len) };
-            let addr = IpAddress::from(Ipv4Address::from_bytes(buf));
-            let port = arg4 as u16;
-            service::connect(handle, addr, port) as usize
+            if let Ok(buf) = buf.try_into() {
+                let addr = IpAddress::from(Ipv4Address::from_octets(buf));
+                let port = arg4 as u16;
+                service::connect(handle, addr, port) as usize
+            } else {
+                -1 as isize as usize
+            }
         }
         number::LISTEN => {
             let handle = arg1;
@@ -118,8 +123,8 @@ pub fn dispatcher(
             let ptr = sys::process::ptr_from_addr(arg2 as u64);
             let len = arg3;
             let buf = unsafe { core::slice::from_raw_parts_mut(ptr, len) };
-            if let Ok(addr) = service::accept(handle) {
-                buf[0..len].clone_from_slice(addr.as_bytes());
+            if let Ok(IpAddress::Ipv4(addr)) = service::accept(handle) {
+                buf[0..len].clone_from_slice(&addr.octets());
                 0
             } else {
                 -1 as isize as usize
diff --git a/src/usr/host.rs b/src/usr/host.rs
index 75d82ade..d7910f3d 100644
--- a/src/usr/host.rs
+++ b/src/usr/host.rs
@@ -168,11 +168,15 @@ pub fn resolve(name: &str) -> Result<IpAddress, ResponseCode> {
                             // the last 4 bytes
                             let n = message.datagram.len();
                             let data = &message.datagram[(n - 4)..];
-                            let ipv4 = Ipv4Address::from_bytes(data);
-                            if ipv4.is_unspecified() {
-                                Err(ResponseCode::NameError) // FIXME
+                            if let Ok(data) = data.try_into() {
+                                let ipv4 = Ipv4Address::from_octets(data);
+                                if ipv4.is_unspecified() {
+                                    Err(ResponseCode::NameError) // FIXME
+                                } else {
+                                    Ok(IpAddress::from(ipv4))
+                                }
                             } else {
-                                Ok(IpAddress::from(ipv4))
+                                Err(ResponseCode::NameError) // FIXME
                             }
                         }
                         code => Err(code),