diff --git a/src/header/sys_time/mod.rs b/src/header/sys_time/mod.rs
index 9eecc9fdad..3d6193996d 100644
--- a/src/header/sys_time/mod.rs
+++ b/src/header/sys_time/mod.rs
@@ -2,6 +2,9 @@
 //!
 //! See <https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_time.h.html>.
 
+// TODO: set this for entire crate when possible
+#![deny(unsafe_op_in_unsafe_fn)]
+
 use crate::{
     c_str::CStr,
     error::ResultExt,
@@ -85,7 +88,7 @@ pub struct timezone {
 #[deprecated]
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn getitimer(which: c_int, value: *mut itimerval) -> c_int {
-    Sys::getitimer(which, &mut *value)
+    Sys::getitimer(which, unsafe { &mut *value })
         .map(|()| 0)
         .or_minus_one_errno()
 }
@@ -101,7 +104,7 @@ pub unsafe extern "C" fn getitimer(which: c_int, value: *mut itimerval) -> c_int
 #[deprecated]
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn gettimeofday(tp: *mut timeval, tzp: *mut timezone) -> c_int {
-    Sys::gettimeofday(Out::nonnull(tp), Out::nullable(tzp))
+    Sys::gettimeofday(unsafe { Out::nonnull(tp) }, unsafe { Out::nullable(tzp) })
         .map(|()| 0)
         .or_minus_one_errno()
 }
@@ -121,7 +124,7 @@ pub unsafe extern "C" fn setitimer(
     ovalue: *mut itimerval,
 ) -> c_int {
     // TODO setitimer is unimplemented on Redox
-    Sys::setitimer(which, &*value, ovalue.as_mut())
+    Sys::setitimer(which, unsafe { &*value }, unsafe { ovalue.as_mut() })
         .map(|()| 0)
         .or_minus_one_errno()
 }
@@ -133,7 +136,7 @@ pub unsafe extern "C" fn setitimer(
 /// Specifications Issue 6, and then unmarked in Issue 7.
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn utimes(path: *const c_char, times: *const timeval) -> c_int {
-    let path = CStr::from_ptr(path);
+    let path = unsafe { CStr::from_ptr(path) };
     // Nullptr is valid here, it means "use current time"
     let times_spec = if times.is_null() {
         null()
@@ -141,18 +144,18 @@ pub unsafe extern "C" fn utimes(path: *const c_char, times: *const timeval) -> c
         {
             [
                 timespec {
-                    tv_sec: (*times.offset(0)).tv_sec,
-                    tv_nsec: ((*times.offset(0)).tv_usec as c_long) * 1000,
+                    tv_sec: unsafe { (*times.offset(0)).tv_sec },
+                    tv_nsec: (unsafe { (*times.offset(0)).tv_usec } as c_long) * 1000,
                 },
                 timespec {
-                    tv_sec: (*times.offset(1)).tv_sec,
-                    tv_nsec: ((*times.offset(1)).tv_usec as c_long) * 1000,
+                    tv_sec: unsafe { (*times.offset(1)).tv_sec },
+                    tv_nsec: (unsafe { (*times.offset(1)).tv_usec } as c_long) * 1000,
                 },
             ]
         }
         .as_ptr()
     };
-    Sys::utimens(path, times_spec)
+    unsafe { Sys::utimens(path, times_spec) }
         .map(|()| 0)
         .or_minus_one_errno()
 }