Merge pull request #4004 from YohDeadfall/thread-name-ice-fix

Get/set thread name shims return errors for invalid handles

12 files changed, 192 insertions, 109 deletions

diff --git a/src/tools/miri/src/concurrency/thread.rs b/src/tools/miri/src/concurrency/thread.rs
index 281242bf373..7477494281d 100644
--- a/src/tools/miri/src/concurrency/thread.rs
+++ b/src/tools/miri/src/concurrency/thread.rs
@@ -1,7 +1,6 @@
 //! Implements threads.
 
 use std::mem;
-use std::num::TryFromIntError;
 use std::sync::atomic::Ordering::Relaxed;
 use std::task::Poll;
 use std::time::{Duration, SystemTime};
@@ -127,26 +126,6 @@ impl Idx for ThreadId {
     }
 }
 
-impl TryFrom<u64> for ThreadId {
-    type Error = TryFromIntError;
-    fn try_from(id: u64) -> Result<Self, Self::Error> {
-        u32::try_from(id).map(Self)
-    }
-}
-
-impl TryFrom<i128> for ThreadId {
-    type Error = TryFromIntError;
-    fn try_from(id: i128) -> Result<Self, Self::Error> {
-        u32::try_from(id).map(Self)
-    }
-}
-
-impl From<u32> for ThreadId {
-    fn from(id: u32) -> Self {
-        Self(id)
-    }
-}
-
 impl From<ThreadId> for u64 {
     fn from(t: ThreadId) -> Self {
         t.0.into()
@@ -448,6 +427,10 @@ pub enum TimeoutAnchor {
     Absolute,
 }
 
+/// An error signaling that the requested thread doesn't exist.
+#[derive(Debug, Copy, Clone)]
+pub struct ThreadNotFound;
+
 /// A set of threads.
 #[derive(Debug)]
 pub struct ThreadManager<'tcx> {
@@ -509,6 +492,16 @@ impl<'tcx> ThreadManager<'tcx> {
         }
     }
 
+    pub fn thread_id_try_from(&self, id: impl TryInto<u32>) -> Result<ThreadId, ThreadNotFound> {
+        if let Ok(id) = id.try_into()
+            && usize::try_from(id).is_ok_and(|id| id < self.threads.len())
+        {
+            Ok(ThreadId(id))
+        } else {
+            Err(ThreadNotFound)
+        }
+    }
+
     /// Check if we have an allocation for the given thread local static for the
     /// active thread.
     fn get_thread_local_alloc_id(&self, def_id: DefId) -> Option<StrictPointer> {
@@ -534,6 +527,7 @@ impl<'tcx> ThreadManager<'tcx> {
     ) -> &mut Vec<Frame<'tcx, Provenance, FrameExtra<'tcx>>> {
         &mut self.threads[self.active_thread].stack
     }
+
     pub fn all_stacks(
         &self,
     ) -> impl Iterator<Item = (ThreadId, &[Frame<'tcx, Provenance, FrameExtra<'tcx>>])> {
@@ -868,6 +862,11 @@ trait EvalContextPrivExt<'tcx>: MiriInterpCxExt<'tcx> {
 // Public interface to thread management.
 impl<'tcx> EvalContextExt<'tcx> for crate::MiriInterpCx<'tcx> {}
 pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
+    #[inline]
+    fn thread_id_try_from(&self, id: impl TryInto<u32>) -> Result<ThreadId, ThreadNotFound> {
+        self.eval_context_ref().machine.threads.thread_id_try_from(id)
+    }
+
     /// Get a thread-specific allocation id for the given thread-local static.
     /// If needed, allocate a new one.
     fn get_or_create_thread_local_alloc(
@@ -1160,8 +1159,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     /// Set the name of the current thread. The buffer must not include the null terminator.
     #[inline]
     fn set_thread_name(&mut self, thread: ThreadId, new_thread_name: Vec<u8>) {
-        let this = self.eval_context_mut();
-        this.machine.threads.set_thread_name(thread, new_thread_name);
+        self.eval_context_mut().machine.threads.set_thread_name(thread, new_thread_name);
     }
 
     #[inline]
diff --git a/src/tools/miri/src/shims/unix/android/thread.rs b/src/tools/miri/src/shims/unix/android/thread.rs
index 1da13d48252..093b7405ccd 100644
--- a/src/tools/miri/src/shims/unix/android/thread.rs
+++ b/src/tools/miri/src/shims/unix/android/thread.rs
@@ -2,7 +2,7 @@ use rustc_abi::{ExternAbi, Size};
 use rustc_span::Symbol;
 
 use crate::helpers::check_min_arg_count;
-use crate::shims::unix::thread::EvalContextExt as _;
+use crate::shims::unix::thread::{EvalContextExt as _, ThreadNameResult};
 use crate::*;
 
 const TASK_COMM_LEN: usize = 16;
@@ -32,7 +32,7 @@ pub fn prctl<'tcx>(
             // https://www.man7.org/linux/man-pages/man2/PR_SET_NAME.2const.html
             let res =
                 this.pthread_setname_np(thread, name, TASK_COMM_LEN, /* truncate */ true)?;
-            assert!(res);
+            assert_eq!(res, ThreadNameResult::Ok);
             Scalar::from_u32(0)
         }
         op if op == pr_get_name => {
@@ -46,7 +46,7 @@ pub fn prctl<'tcx>(
                 CheckInAllocMsg::MemoryAccessTest,
             )?;
             let res = this.pthread_getname_np(thread, name, len, /* truncate*/ false)?;
-            assert!(res);
+            assert_eq!(res, ThreadNameResult::Ok);
             Scalar::from_u32(0)
         }
         op => throw_unsup_format!("Miri does not support `prctl` syscall with op={}", op),
diff --git a/src/tools/miri/src/shims/unix/foreign_items.rs b/src/tools/miri/src/shims/unix/foreign_items.rs
index d59d6712c4f..55202a08149 100644
--- a/src/tools/miri/src/shims/unix/foreign_items.rs
+++ b/src/tools/miri/src/shims/unix/foreign_items.rs
@@ -603,13 +603,13 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             }
             "pthread_join" => {
                 let [thread, retval] = this.check_shim(abi, ExternAbi::C { unwind: false }, link_name, args)?;
-                this.pthread_join(thread, retval)?;
-                this.write_null(dest)?;
+                let res = this.pthread_join(thread, retval)?;
+                this.write_scalar(res, dest)?;
             }
             "pthread_detach" => {
                 let [thread] = this.check_shim(abi, ExternAbi::C { unwind: false }, link_name, args)?;
-                this.pthread_detach(thread)?;
-                this.write_null(dest)?;
+                let res = this.pthread_detach(thread)?;
+                this.write_scalar(res, dest)?;
             }
             "pthread_self" => {
                 let [] = this.check_shim(abi, ExternAbi::C { unwind: false }, link_name, args)?;
diff --git a/src/tools/miri/src/shims/unix/linux/foreign_items.rs b/src/tools/miri/src/shims/unix/linux/foreign_items.rs
index 35658ebc2f2..85f0d6e1330 100644
--- a/src/tools/miri/src/shims/unix/linux/foreign_items.rs
+++ b/src/tools/miri/src/shims/unix/linux/foreign_items.rs
@@ -81,13 +81,17 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             "pthread_setname_np" => {
                 let [thread, name] =
                     this.check_shim(abi, ExternAbi::C { unwind: false }, link_name, args)?;
-                let res = this.pthread_setname_np(
+                let res = match this.pthread_setname_np(
                     this.read_scalar(thread)?,
                     this.read_scalar(name)?,
                     TASK_COMM_LEN,
                     /* truncate */ false,
-                )?;
-                let res = if res { Scalar::from_u32(0) } else { this.eval_libc("ERANGE") };
+                )? {
+                    ThreadNameResult::Ok => Scalar::from_u32(0),
+                    ThreadNameResult::NameTooLong => this.eval_libc("ERANGE"),
+                    // Act like we faild to open `/proc/self/task/$tid/comm`.
+                    ThreadNameResult::ThreadNotFound => this.eval_libc("ENOENT"),
+                };
                 this.write_scalar(res, dest)?;
             }
             "pthread_getname_np" => {
@@ -97,14 +101,18 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 // In case of glibc, the length of the output buffer must
                 // be not shorter than TASK_COMM_LEN.
                 let len = this.read_scalar(len)?;
-                let res = if len.to_target_usize(this)? >= TASK_COMM_LEN as u64
-                    && this.pthread_getname_np(
+                let res = if len.to_target_usize(this)? >= TASK_COMM_LEN as u64 {
+                    match this.pthread_getname_np(
                         this.read_scalar(thread)?,
                         this.read_scalar(name)?,
                         len,
                         /* truncate*/ false,
                     )? {
-                    Scalar::from_u32(0)
+                        ThreadNameResult::Ok => Scalar::from_u32(0),
+                        ThreadNameResult::NameTooLong => unreachable!(),
+                        // Act like we faild to open `/proc/self/task/$tid/comm`.
+                        ThreadNameResult::ThreadNotFound => this.eval_libc("ENOENT"),
+                    }
                 } else {
                     this.eval_libc("ERANGE")
                 };
diff --git a/src/tools/miri/src/shims/unix/macos/foreign_items.rs b/src/tools/miri/src/shims/unix/macos/foreign_items.rs
index b77b46e325d..003025916cd 100644
--- a/src/tools/miri/src/shims/unix/macos/foreign_items.rs
+++ b/src/tools/miri/src/shims/unix/macos/foreign_items.rs
@@ -181,18 +181,16 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 // are met, then the name is set and 0 is returned. Otherwise, if
                 // the specified name is lomnger than MAXTHREADNAMESIZE, then
                 // ENAMETOOLONG is returned.
-                //
-                // FIXME: the real implementation maybe returns ESRCH if the thread ID is invalid.
                 let thread = this.pthread_self()?;
-                let res = if this.pthread_setname_np(
+                let res = match this.pthread_setname_np(
                     thread,
                     this.read_scalar(name)?,
                     this.eval_libc("MAXTHREADNAMESIZE").to_target_usize(this)?.try_into().unwrap(),
                     /* truncate */ false,
                 )? {
-                    Scalar::from_u32(0)
-                } else {
-                    this.eval_libc("ENAMETOOLONG")
+                    ThreadNameResult::Ok => Scalar::from_u32(0),
+                    ThreadNameResult::NameTooLong => this.eval_libc("ENAMETOOLONG"),
+                    ThreadNameResult::ThreadNotFound => unreachable!(),
                 };
                 // Contrary to the manpage, `pthread_setname_np` on macOS still
                 // returns an integer indicating success.
@@ -210,15 +208,17 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 // https://github.com/apple-oss-distributions/libpthread/blob/c032e0b076700a0a47db75528a282b8d3a06531a/src/pthread.c#L1160-L1175.
                 // The key part is the strlcpy, which truncates the resulting value,
                 // but always null terminates (except for zero sized buffers).
-                //
-                // FIXME: the real implementation returns ESRCH if the thread ID is invalid.
-                let res = Scalar::from_u32(0);
-                this.pthread_getname_np(
+                let res = match this.pthread_getname_np(
                     this.read_scalar(thread)?,
                     this.read_scalar(name)?,
                     this.read_scalar(len)?,
                     /* truncate */ true,
-                )?;
+                )? {
+                    ThreadNameResult::Ok => Scalar::from_u32(0),
+                    // `NameTooLong` is possible when the buffer is zero sized,
+                    ThreadNameResult::NameTooLong => Scalar::from_u32(0),
+                    ThreadNameResult::ThreadNotFound => this.eval_libc("ESRCH"),
+                };
                 this.write_scalar(res, dest)?;
             }
 
diff --git a/src/tools/miri/src/shims/unix/mod.rs b/src/tools/miri/src/shims/unix/mod.rs
index 9bc310e8d0a..c8c25c636ee 100644
--- a/src/tools/miri/src/shims/unix/mod.rs
+++ b/src/tools/miri/src/shims/unix/mod.rs
@@ -21,7 +21,7 @@ pub use self::fs::{DirTable, EvalContextExt as _};
 pub use self::linux::epoll::EpollInterestTable;
 pub use self::mem::EvalContextExt as _;
 pub use self::sync::EvalContextExt as _;
-pub use self::thread::EvalContextExt as _;
+pub use self::thread::{EvalContextExt as _, ThreadNameResult};
 pub use self::unnamed_socket::EvalContextExt as _;
 
 // Make up some constants.
diff --git a/src/tools/miri/src/shims/unix/solarish/foreign_items.rs b/src/tools/miri/src/shims/unix/solarish/foreign_items.rs
index efdc64f45fc..526b64cff69 100644
--- a/src/tools/miri/src/shims/unix/solarish/foreign_items.rs
+++ b/src/tools/miri/src/shims/unix/solarish/foreign_items.rs
@@ -26,26 +26,33 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 // THREAD_NAME_MAX allows a thread name of 31+1 length
                 // https://github.com/illumos/illumos-gate/blob/7671517e13b8123748eda4ef1ee165c6d9dba7fe/usr/src/uts/common/sys/thread.h#L613
                 let max_len = 32;
-                let res = this.pthread_setname_np(
+                // See https://illumos.org/man/3C/pthread_setname_np for the error codes.
+                let res = match this.pthread_setname_np(
                     this.read_scalar(thread)?,
                     this.read_scalar(name)?,
                     max_len,
                     /* truncate */ false,
-                )?;
-                let res = if res { Scalar::from_u32(0) } else { this.eval_libc("ERANGE") };
+                )? {
+                    ThreadNameResult::Ok => Scalar::from_u32(0),
+                    ThreadNameResult::NameTooLong => this.eval_libc("ERANGE"),
+                    ThreadNameResult::ThreadNotFound => this.eval_libc("ESRCH"),
+                };
                 this.write_scalar(res, dest)?;
             }
             "pthread_getname_np" => {
                 let [thread, name, len] =
                     this.check_shim(abi, ExternAbi::C { unwind: false }, link_name, args)?;
-                // https://github.com/illumos/illumos-gate/blob/c56822be04b6c157c8b6f2281e47214c3b86f657/usr/src/lib/libc/port/threads/thr.c#L2449-L2480
-                let res = this.pthread_getname_np(
+                // See https://illumos.org/man/3C/pthread_getname_np for the error codes.
+                let res = match this.pthread_getname_np(
                     this.read_scalar(thread)?,
                     this.read_scalar(name)?,
                     this.read_scalar(len)?,
                     /* truncate */ false,
-                )?;
-                let res = if res { Scalar::from_u32(0) } else { this.eval_libc("ERANGE") };
+                )? {
+                    ThreadNameResult::Ok => Scalar::from_u32(0),
+                    ThreadNameResult::NameTooLong => this.eval_libc("ERANGE"),
+                    ThreadNameResult::ThreadNotFound => this.eval_libc("ESRCH"),
+                };
                 this.write_scalar(res, dest)?;
             }
 
diff --git a/src/tools/miri/src/shims/unix/thread.rs b/src/tools/miri/src/shims/unix/thread.rs
index 52c135f8540..3d990a1a042 100644
--- a/src/tools/miri/src/shims/unix/thread.rs
+++ b/src/tools/miri/src/shims/unix/thread.rs
@@ -2,6 +2,13 @@ use rustc_abi::ExternAbi;
 
 use crate::*;
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum ThreadNameResult {
+    Ok,
+    NameTooLong,
+    ThreadNotFound,
+}
+
 impl<'tcx> EvalContextExt<'tcx> for crate::MiriInterpCx<'tcx> {}
 pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     fn pthread_create(
@@ -30,7 +37,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         interp_ok(())
     }
 
-    fn pthread_join(&mut self, thread: &OpTy<'tcx>, retval: &OpTy<'tcx>) -> InterpResult<'tcx, ()> {
+    fn pthread_join(
+        &mut self,
+        thread: &OpTy<'tcx>,
+        retval: &OpTy<'tcx>,
+    ) -> InterpResult<'tcx, Scalar> {
         let this = self.eval_context_mut();
 
         if !this.ptr_is_null(this.read_pointer(retval)?)? {
@@ -38,22 +49,26 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             throw_unsup_format!("Miri supports pthread_join only with retval==NULL");
         }
 
-        let thread_id = this.read_scalar(thread)?.to_int(this.libc_ty_layout("pthread_t").size)?;
-        this.join_thread_exclusive(thread_id.try_into().expect("thread ID should fit in u32"))?;
+        let thread = this.read_scalar(thread)?.to_int(this.libc_ty_layout("pthread_t").size)?;
+        let Ok(thread) = this.thread_id_try_from(thread) else {
+            return interp_ok(this.eval_libc("ESRCH"));
+        };
 
-        interp_ok(())
+        this.join_thread_exclusive(thread)?;
+
+        interp_ok(Scalar::from_u32(0))
     }
 
-    fn pthread_detach(&mut self, thread: &OpTy<'tcx>) -> InterpResult<'tcx, ()> {
+    fn pthread_detach(&mut self, thread: &OpTy<'tcx>) -> InterpResult<'tcx, Scalar> {
         let this = self.eval_context_mut();
 
-        let thread_id = this.read_scalar(thread)?.to_int(this.libc_ty_layout("pthread_t").size)?;
-        this.detach_thread(
-            thread_id.try_into().expect("thread ID should fit in u32"),
-            /*allow_terminated_joined*/ false,
-        )?;
+        let thread = this.read_scalar(thread)?.to_int(this.libc_ty_layout("pthread_t").size)?;
+        let Ok(thread) = this.thread_id_try_from(thread) else {
+            return interp_ok(this.eval_libc("ESRCH"));
+        };
+        this.detach_thread(thread, /*allow_terminated_joined*/ false)?;
 
-        interp_ok(())
+        interp_ok(Scalar::from_u32(0))
     }
 
     fn pthread_self(&mut self) -> InterpResult<'tcx, Scalar> {
@@ -65,18 +80,21 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
     /// Set the name of the specified thread. If the name including the null terminator
     /// is longer or equals to `name_max_len`, then if `truncate` is set the truncated name
-    /// is used as the thread name, otherwise `false` is returned.
+    /// is used as the thread name, otherwise [`ThreadNameResult::NameTooLong`] is returned.
+    /// If the specified thread wasn't found, [`ThreadNameResult::ThreadNotFound`] is returned.
     fn pthread_setname_np(
         &mut self,
         thread: Scalar,
         name: Scalar,
         name_max_len: usize,
         truncate: bool,
-    ) -> InterpResult<'tcx, bool> {
+    ) -> InterpResult<'tcx, ThreadNameResult> {
         let this = self.eval_context_mut();
 
         let thread = thread.to_int(this.libc_ty_layout("pthread_t").size)?;
-        let thread = ThreadId::try_from(thread).unwrap();
+        let Ok(thread) = this.thread_id_try_from(thread) else {
+            return interp_ok(ThreadNameResult::ThreadNotFound);
+        };
         let name = name.to_pointer(this)?;
         let mut name = this.read_c_str(name)?.to_owned();
 
@@ -85,29 +103,32 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             if truncate {
                 name.truncate(name_max_len.saturating_sub(1));
             } else {
-                return interp_ok(false);
+                return interp_ok(ThreadNameResult::NameTooLong);
             }
         }
 
         this.set_thread_name(thread, name);
 
-        interp_ok(true)
+        interp_ok(ThreadNameResult::Ok)
     }
 
     /// Get the name of the specified thread. If the thread name doesn't fit
     /// the buffer, then if `truncate` is set the truncated name is written out,
-    /// otherwise `false` is returned.
+    /// otherwise [`ThreadNameResult::NameTooLong`] is returned. If the specified
+    /// thread wasn't found, [`ThreadNameResult::ThreadNotFound`] is returned.
     fn pthread_getname_np(
         &mut self,
         thread: Scalar,
         name_out: Scalar,
         len: Scalar,
         truncate: bool,
-    ) -> InterpResult<'tcx, bool> {
+    ) -> InterpResult<'tcx, ThreadNameResult> {
         let this = self.eval_context_mut();
 
         let thread = thread.to_int(this.libc_ty_layout("pthread_t").size)?;
-        let thread = ThreadId::try_from(thread).unwrap();
+        let Ok(thread) = this.thread_id_try_from(thread) else {
+            return interp_ok(ThreadNameResult::ThreadNotFound);
+        };
         let name_out = name_out.to_pointer(this)?;
         let len = len.to_target_usize(this)?;
 
@@ -119,8 +140,9 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         };
 
         let (success, _written) = this.write_c_str(name, name_out, len)?;
+        let res = if success { ThreadNameResult::Ok } else { ThreadNameResult::NameTooLong };
 
-        interp_ok(success)
+        interp_ok(res)
     }
 
     fn sched_yield(&mut self) -> InterpResult<'tcx, ()> {
diff --git a/src/tools/miri/src/shims/windows/foreign_items.rs b/src/tools/miri/src/shims/windows/foreign_items.rs
index fe11aa8da4a..504efed3cfd 100644
--- a/src/tools/miri/src/shims/windows/foreign_items.rs
+++ b/src/tools/miri/src/shims/windows/foreign_items.rs
@@ -10,6 +10,10 @@ use crate::shims::os_str::bytes_to_os_str;
 use crate::shims::windows::*;
 use crate::*;
 
+// The NTSTATUS STATUS_INVALID_HANDLE (0xC0000008) encoded as a HRESULT by setting the N bit.
+// (https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/0642cb2f-2075-4469-918c-4441e69c548a)
+const STATUS_INVALID_HANDLE: u32 = 0xD0000008;
+
 pub fn is_dyn_sym(name: &str) -> bool {
     // std does dynamic detection for these symbols
     matches!(
@@ -484,14 +488,14 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let thread_id =
                     this.CreateThread(security, stacksize, start, arg, flags, thread)?;
 
-                this.write_scalar(Handle::Thread(thread_id).to_scalar(this), dest)?;
+                this.write_scalar(Handle::Thread(thread_id.to_u32()).to_scalar(this), dest)?;
             }
             "WaitForSingleObject" => {
                 let [handle, timeout] =
                     this.check_shim(abi, ExternAbi::System { unwind: false }, link_name, args)?;
 
                 let ret = this.WaitForSingleObject(handle, timeout)?;
-                this.write_scalar(Scalar::from_u32(ret), dest)?;
+                this.write_scalar(ret, dest)?;
             }
             "GetCurrentThread" => {
                 let [] =
@@ -510,15 +514,20 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let name = this.read_wide_str(this.read_pointer(name)?)?;
 
                 let thread = match Handle::from_scalar(handle, this)? {
-                    Some(Handle::Thread(thread)) => thread,
-                    Some(Handle::Pseudo(PseudoHandle::CurrentThread)) => this.active_thread(),
+                    Some(Handle::Thread(thread)) => this.thread_id_try_from(thread),
+                    Some(Handle::Pseudo(PseudoHandle::CurrentThread)) => Ok(this.active_thread()),
                     _ => this.invalid_handle("SetThreadDescription")?,
                 };
+                let res = match thread {
+                    Ok(thread) => {
+                        // FIXME: use non-lossy conversion
+                        this.set_thread_name(thread, String::from_utf16_lossy(&name).into_bytes());
+                        Scalar::from_u32(0)
+                    }
+                    Err(_) => Scalar::from_u32(STATUS_INVALID_HANDLE),
+                };
 
-                // FIXME: use non-lossy conversion
-                this.set_thread_name(thread, String::from_utf16_lossy(&name).into_bytes());
-
-                this.write_null(dest)?;
+                this.write_scalar(res, dest)?;
             }
             "GetThreadDescription" => {
                 let [handle, name_ptr] =
@@ -528,20 +537,25 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let name_ptr = this.deref_pointer(name_ptr)?; // the pointer where we should store the ptr to the name
 
                 let thread = match Handle::from_scalar(handle, this)? {
-                    Some(Handle::Thread(thread)) => thread,
-                    Some(Handle::Pseudo(PseudoHandle::CurrentThread)) => this.active_thread(),
+                    Some(Handle::Thread(thread)) => this.thread_id_try_from(thread),
+                    Some(Handle::Pseudo(PseudoHandle::CurrentThread)) => Ok(this.active_thread()),
                     _ => this.invalid_handle("GetThreadDescription")?,
                 };
-                // Looks like the default thread name is empty.
-                let name = this.get_thread_name(thread).unwrap_or(b"").to_owned();
-                let name = this.alloc_os_str_as_wide_str(
-                    bytes_to_os_str(&name)?,
-                    MiriMemoryKind::WinLocal.into(),
-                )?;
-
-                this.write_scalar(Scalar::from_maybe_pointer(name, this), &name_ptr)?;
+                let (name, res) = match thread {
+                    Ok(thread) => {
+                        // Looks like the default thread name is empty.
+                        let name = this.get_thread_name(thread).unwrap_or(b"").to_owned();
+                        let name = this.alloc_os_str_as_wide_str(
+                            bytes_to_os_str(&name)?,
+                            MiriMemoryKind::WinLocal.into(),
+                        )?;
+                        (Scalar::from_maybe_pointer(name, this), Scalar::from_u32(0))
+                    }
+                    Err(_) => (Scalar::null_ptr(this), Scalar::from_u32(STATUS_INVALID_HANDLE)),
+                };
 
-                this.write_null(dest)?;
+                this.write_scalar(name, &name_ptr)?;
+                this.write_scalar(res, dest)?;
             }
 
             // Miscellaneous
@@ -630,9 +644,9 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let [handle] =
                     this.check_shim(abi, ExternAbi::System { unwind: false }, link_name, args)?;
 
-                this.CloseHandle(handle)?;
+                let ret = this.CloseHandle(handle)?;
 
-                this.write_int(1, dest)?;
+                this.write_scalar(ret, dest)?;
             }
             "GetModuleFileNameW" => {
                 let [handle, filename, size] =
diff --git a/src/tools/miri/src/shims/windows/handle.rs b/src/tools/miri/src/shims/windows/handle.rs
index 437a21534c9..b40c00efedd 100644
--- a/src/tools/miri/src/shims/windows/handle.rs
+++ b/src/tools/miri/src/shims/windows/handle.rs
@@ -14,7 +14,7 @@ pub enum PseudoHandle {
 pub enum Handle {
     Null,
     Pseudo(PseudoHandle),
-    Thread(ThreadId),
+    Thread(u32),
 }
 
 impl PseudoHandle {
@@ -51,7 +51,7 @@ impl Handle {
         match self {
             Self::Null => 0,
             Self::Pseudo(pseudo_handle) => pseudo_handle.value(),
-            Self::Thread(thread) => thread.to_u32(),
+            Self::Thread(thread) => thread,
         }
     }
 
@@ -95,7 +95,7 @@ impl Handle {
         match discriminant {
             Self::NULL_DISCRIMINANT if data == 0 => Some(Self::Null),
             Self::PSEUDO_DISCRIMINANT => Some(Self::Pseudo(PseudoHandle::from_value(data)?)),
-            Self::THREAD_DISCRIMINANT => Some(Self::Thread(data.into())),
+            Self::THREAD_DISCRIMINANT => Some(Self::Thread(data)),
             _ => None,
         }
     }
@@ -154,17 +154,22 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         )))
     }
 
-    fn CloseHandle(&mut self, handle_op: &OpTy<'tcx>) -> InterpResult<'tcx> {
+    fn CloseHandle(&mut self, handle_op: &OpTy<'tcx>) -> InterpResult<'tcx, Scalar> {
         let this = self.eval_context_mut();
 
         let handle = this.read_scalar(handle_op)?;
-
-        match Handle::from_scalar(handle, this)? {
-            Some(Handle::Thread(thread)) =>
-                this.detach_thread(thread, /*allow_terminated_joined*/ true)?,
+        let ret = match Handle::from_scalar(handle, this)? {
+            Some(Handle::Thread(thread)) => {
+                if let Ok(thread) = this.thread_id_try_from(thread) {
+                    this.detach_thread(thread, /*allow_terminated_joined*/ true)?;
+                    this.eval_windows("c", "TRUE")
+                } else {
+                    this.invalid_handle("CloseHandle")?
+                }
+            }
             _ => this.invalid_handle("CloseHandle")?,
-        }
+        };
 
-        interp_ok(())
+        interp_ok(ret)
     }
 }
diff --git a/src/tools/miri/src/shims/windows/thread.rs b/src/tools/miri/src/shims/windows/thread.rs
index fd3ef1413ed..7af15fc647c 100644
--- a/src/tools/miri/src/shims/windows/thread.rs
+++ b/src/tools/miri/src/shims/windows/thread.rs
@@ -59,14 +59,18 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         &mut self,
         handle_op: &OpTy<'tcx>,
         timeout_op: &OpTy<'tcx>,
-    ) -> InterpResult<'tcx, u32> {
+    ) -> InterpResult<'tcx, Scalar> {
         let this = self.eval_context_mut();
 
         let handle = this.read_scalar(handle_op)?;
         let timeout = this.read_scalar(timeout_op)?.to_u32()?;
 
         let thread = match Handle::from_scalar(handle, this)? {
-            Some(Handle::Thread(thread)) => thread,
+            Some(Handle::Thread(thread)) =>
+                match this.thread_id_try_from(thread) {
+                    Ok(thread) => thread,
+                    Err(_) => this.invalid_handle("WaitForSingleObject")?,
+                },
             // Unlike on posix, the outcome of joining the current thread is not documented.
             // On current Windows, it just deadlocks.
             Some(Handle::Pseudo(PseudoHandle::CurrentThread)) => this.active_thread(),
@@ -79,6 +83,6 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         this.join_thread(thread)?;
 
-        interp_ok(0)
+        interp_ok(this.eval_windows("c", "WAIT_OBJECT_0"))
     }
 }
diff --git a/src/tools/miri/tests/pass-dep/libc/pthread-threadname.rs b/src/tools/miri/tests/pass-dep/libc/pthread-threadname.rs
index 0e5b501bbcc..cf634bc6890 100644
--- a/src/tools/miri/tests/pass-dep/libc/pthread-threadname.rs
+++ b/src/tools/miri/tests/pass-dep/libc/pthread-threadname.rs
@@ -199,4 +199,29 @@ fn main() {
         .unwrap()
         .join()
         .unwrap();
+
+    // Now set the name for a non-existing thread and verify error codes.
+    // (FreeBSD doesn't return an error code.)
+    #[cfg(not(target_os = "freebsd"))]
+    {
+        let invalid_thread = 0xdeadbeef;
+        let error = {
+            cfg_if::cfg_if! {
+                if #[cfg(target_os = "linux")] {
+                    libc::ENOENT
+                } else {
+                    libc::ESRCH
+                }
+            }
+        };
+        #[cfg(not(target_os = "macos"))]
+        {
+            // macOS has no `setname` function accepting a thread id as the first argument.
+            let res = unsafe { libc::pthread_setname_np(invalid_thread, [0].as_ptr()) };
+            assert_eq!(res, error);
+        }
+        let mut buf = [0; 64];
+        let res = unsafe { libc::pthread_getname_np(invalid_thread, buf.as_mut_ptr(), buf.len()) };
+        assert_eq!(res, error);
+    }
 }