Merge pull request #3984 from noahmbright/unix_shims

Clear `eval_libc` errors from unix shims

Author: RalfJung

src/tools/miri/src/shims/foreign_items.rs

@@ -447,8 +447,7 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
 }else{
 // If this does not fit in an isize, return null and, on Unix, set errno.
 if this.target_os_is_unix(){
-let einval = this.eval_libc("ENOMEM");
- this.set_last_error(einval)?;
+ this.set_last_error(LibcError("ENOMEM"))?;
 }
  this.write_null(dest)?;
 }
@@ -464,8 +463,7 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
 }else{
 // On size overflow, return null and, on Unix, set errno.
 if this.target_os_is_unix(){
-let einval = this.eval_libc("ENOMEM");
- this.set_last_error(einval)?;
+ this.set_last_error(LibcError("ENOMEM"))?;
 }
  this.write_null(dest)?;
 }
@@ -486,8 +484,7 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
 }else{
 // If this does not fit in an isize, return null and, on Unix, set errno.
 if this.target_os_is_unix(){
-let einval = this.eval_libc("ENOMEM");
- this.set_last_error(einval)?;
+ this.set_last_error(LibcError("ENOMEM"))?;
 }
  this.write_null(dest)?;
 }

src/tools/miri/src/shims/time.rs

@@ -81,9 +81,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 }elseif relative_clocks.contains(&clk_id){
  this.machine.clock.now().duration_since(this.machine.clock.epoch())
 }else{
-let einval = this.eval_libc("EINVAL");
- this.set_last_error(einval)?;
-returninterp_ok(Scalar::from_i32(-1));
+return this.set_last_error_and_return_i32(LibcError("EINVAL"));
 };
 
 let tv_sec = duration.as_secs();
@@ -109,9 +107,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 // Using tz is obsolete and should always be null
 let tz = this.read_pointer(tz_op)?;
 if !this.ptr_is_null(tz)? {
-let einval = this.eval_libc("EINVAL");
- this.set_last_error(einval)?;
-returninterp_ok(Scalar::from_i32(-1));
+return this.set_last_error_and_return_i32(LibcError("EINVAL"));
 }
 
 let duration = system_time_to_duration(&SystemTime::now())?;
@@ -323,9 +319,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 let duration = match this.read_timespec(&req)? {
 Some(duration) => duration,
 None => {
-let einval = this.eval_libc("EINVAL");
- this.set_last_error(einval)?;
-returninterp_ok(Scalar::from_i32(-1));
+return this.set_last_error_and_return_i32(LibcError("EINVAL"));
 }
 };
 

src/tools/miri/src/shims/unix/foreign_items.rs

@@ -362,8 +362,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 // FreeBSD: https://man.freebsd.org/cgi/man.cgi?query=reallocarray
 match this.compute_size_in_bytes(Size::from_bytes(size), nmemb){
 None => {
-let enmem = this.eval_libc("ENOMEM");
- this.set_last_error(enmem)?;
+ this.set_last_error(LibcError("ENOMEM"))?;
  this.write_null(dest)?;
 }
 Some(len) => {
@@ -653,13 +652,10 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 let chunk_size = CpuAffinityMask::chunk_size(this);
 
 if this.ptr_is_null(mask)? {
-let efault = this.eval_libc("EFAULT");
- this.set_last_error(efault)?;
- this.write_int(-1, dest)?;
+ this.set_last_error_and_return(LibcError("EFAULT"), dest)?;
 }elseif cpusetsize == 0 || cpusetsize.checked_rem(chunk_size).unwrap() != 0{
 // we only copy whole chunks of size_of::<c_ulong>()
- this.set_last_error(LibcError("EINVAL"))?;
- this.write_int(-1, dest)?;
+ this.set_last_error_and_return(LibcError("EINVAL"), dest)?;
 }elseifletSome(cpuset) = this.machine.thread_cpu_affinity.get(&thread_id){
 let cpuset = cpuset.clone();
 // we only copy whole chunks of size_of::<c_ulong>()
@@ -668,9 +664,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
  this.write_null(dest)?;
 }else{
 // The thread whose ID is pid could not be found
-let esrch = this.eval_libc("ESRCH");
- this.set_last_error(esrch)?;
- this.write_int(-1, dest)?;
+ this.set_last_error_and_return(LibcError("ESRCH"), dest)?;
 }
 }
 "sched_setaffinity" => {
@@ -695,9 +689,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 };
 
 if this.ptr_is_null(mask)? {
-let efault = this.eval_libc("EFAULT");
- this.set_last_error(efault)?;
- this.write_int(-1, dest)?;
+ this.set_last_error_and_return(LibcError("EFAULT"), dest)?;
 }else{
 // NOTE: cpusetsize might be smaller than `CpuAffinityMask::CPU_MASK_BYTES`.
 // Any unspecified bytes are treated as zero here (none of the CPUs are configured).
@@ -713,8 +705,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 }
 None => {
 // The intersection between the mask and the available CPUs was empty.
- this.set_last_error(LibcError("EINVAL"))?;
- this.write_int(-1, dest)?;
+ this.set_last_error_and_return(LibcError("EINVAL"), dest)?;
 }
 }
 }
@@ -770,9 +761,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 // macOS: https://keith.github.io/xcode-man-pages/getentropy.2.html
 // Solaris/Illumos: https://illumos.org/man/3C/getentropy
 if bufsize > 256{
-let err = this.eval_libc("EIO");
- this.set_last_error(err)?;
- this.write_int(-1, dest)?;
+ this.set_last_error_and_return(LibcError("EIO"), dest)?;
 }else{
  this.gen_random(buf, bufsize)?;
  this.write_null(dest)?;

src/tools/miri/src/shims/unix/fs.rs

@@ -787,13 +787,13 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 let ecode = if path.is_absolute() || dirfd == this.eval_libc_i32("AT_FDCWD"){
 // since `path` is provided, either absolute or
 // relative to CWD, `EACCES` is the most relevant.
-this.eval_libc("EACCES")
+LibcError("EACCES")
 }else{
 // `dirfd` is set to target file, and `path` is empty
 // (or we would have hit the `throw_unsup_format`
 // above). `EACCES` would violate the spec.
 assert!(empty_path_flag);
-this.eval_libc("EBADF")
+LibcError("EBADF")
 };
 return this.set_last_error_and_return_i32(ecode);
 }
@@ -1031,8 +1031,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 // Reject if isolation is enabled.
 ifletIsolatedOp::Reject(reject_with) = this.machine.isolated_op{
  this.reject_in_isolation("`readdir`", reject_with)?;
-let eacc = this.eval_libc("EBADF");
- this.set_last_error(eacc)?;
+ this.set_last_error(LibcError("EBADF"))?;
 returninterp_ok(Scalar::null_ptr(this));
 }
 
@@ -1449,11 +1448,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 if fd.is_tty(this.machine.communicate()){
 returninterp_ok(Scalar::from_i32(1));
 }else{
-this.eval_libc("ENOTTY")
+LibcError("ENOTTY")
 }
 }else{
 // FD does not exist
-this.eval_libc("EBADF")
+LibcError("EBADF")
 };
  this.set_last_error(error)?;
 interp_ok(Scalar::from_i32(0))
@@ -1473,8 +1472,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 // Reject if isolation is enabled.
 ifletIsolatedOp::Reject(reject_with) = this.machine.isolated_op{
  this.reject_in_isolation("`realpath`", reject_with)?;
-let eacc = this.eval_libc("EACCES");
- this.set_last_error(eacc)?;
+ this.set_last_error(LibcError("EACCES"))?;
 returninterp_ok(Scalar::from_target_usize(0, this));
 }
 
@@ -1504,8 +1502,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 // Note that we do not explicitly handle `FILENAME_MAX`
 // (different from `PATH_MAX` above) as it is Linux-specific and
 // seems like a bit of a mess anyway: <https://eklitzke.org/path-max-is-tricky>.
-let enametoolong = this.eval_libc("ENAMETOOLONG");
- this.set_last_error(enametoolong)?;
+ this.set_last_error(LibcError("ENAMETOOLONG"))?;
 returninterp_ok(Scalar::from_target_usize(0, this));
 }
  processed_ptr

src/tools/miri/src/shims/unix/linux/mem.rs

@@ -24,7 +24,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 // old_address must be a multiple of the page size
 #[allow(clippy::arithmetic_side_effects)]// PAGE_SIZE is nonzero
 if old_address.addr().bytes() % this.machine.page_size != 0 || new_size == 0{
- this.set_last_error(this.eval_libc("EINVAL"))?;
+ this.set_last_error(LibcError("EINVAL"))?;
 returninterp_ok(this.eval_libc("MAP_FAILED"));
 }
 
@@ -38,7 +38,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
 if flags & this.eval_libc_i32("MREMAP_MAYMOVE") == 0{
 // We only support MREMAP_MAYMOVE, so not passing the flag is just a failure
- this.set_last_error(this.eval_libc("EINVAL"))?;
+ this.set_last_error(LibcError("EINVAL"))?;
 returninterp_ok(this.eval_libc("MAP_FAILED"));
 }
 

src/tools/miri/src/shims/unix/linux/sync.rs

@@ -158,9 +158,7 @@ pub fn futex<'tcx>(
 }else{
 // The futex value doesn't match the expected value, so we return failure
 // right away without sleeping: -1 and errno set to EAGAIN.
-let eagain = this.eval_libc("EAGAIN");
- this.set_last_error(eagain)?;
- this.write_scalar(Scalar::from_target_isize(-1, this), dest)?;
+ this.set_last_error_and_return(LibcError("EAGAIN"), dest)?;
 }
 }
 // FUTEX_WAKE: (int *addr, int op = FUTEX_WAKE, int val)

src/tools/miri/src/shims/unix/mem.rs

@@ -57,11 +57,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
 // First, we do some basic argument validation as required by mmap
 if(flags &(map_private | map_shared)).count_ones() != 1{
- this.set_last_error(this.eval_libc("EINVAL"))?;
+ this.set_last_error(LibcError("EINVAL"))?;
 returninterp_ok(this.eval_libc("MAP_FAILED"));
 }
 if length == 0{
- this.set_last_error(this.eval_libc("EINVAL"))?;
+ this.set_last_error(LibcError("EINVAL"))?;
 returninterp_ok(this.eval_libc("MAP_FAILED"));
 }
 
@@ -103,11 +103,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
 let align = this.machine.page_align();
 letSome(map_length) = length.checked_next_multiple_of(this.machine.page_size)else{
- this.set_last_error(this.eval_libc("EINVAL"))?;
+ this.set_last_error(LibcError("EINVAL"))?;
 returninterp_ok(this.eval_libc("MAP_FAILED"));
 };
 if map_length > this.target_usize_max(){
- this.set_last_error(this.eval_libc("EINVAL"))?;
+ this.set_last_error(LibcError("EINVAL"))?;
 returninterp_ok(this.eval_libc("MAP_FAILED"));
 }
 
@@ -141,7 +141,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 return this.set_last_error_and_return_i32(LibcError("EINVAL"));
 };
 if length > this.target_usize_max(){
- this.set_last_error(this.eval_libc("EINVAL"))?;
+ this.set_last_error(LibcError("EINVAL"))?;
 returninterp_ok(this.eval_libc("MAP_FAILED"));
 }