Merge pull request #688 from aya-rs/get-fd-owned

sys: bpf_prog_get_fd_by_id returns OwnedFd

aya/src/programs/lirc_mode2.rs

@@ -1,5 +1,5 @@
 //! Lirc programs.
-use std::os::fd::{AsRawFd, RawFd};
+use std::os::fd::{AsRawFd, IntoRawFd as _, RawFd};
 
 use crate::{
     generated::{bpf_attach_type::BPF_LIRC_MODE2, bpf_prog_type::BPF_PROG_TYPE_LIRC_MODE2},
@@ -101,12 +101,12 @@ impl LircMode2 {
                 io_error,
             })?;
 
-            prog_fds.push(fd as RawFd);
+            prog_fds.push(fd);
         }
 
         Ok(prog_fds
             .into_iter()
-            .map(|prog_fd| LircLink::new(prog_fd, target_fd.as_raw_fd()))
+            .map(|prog_fd| LircLink::new(prog_fd.into_raw_fd(), target_fd.as_raw_fd()))
             .collect())
     }
 }

aya/src/programs/mod.rs

@@ -69,7 +69,7 @@ use libc::ENOSPC;
 use std::{
     ffi::CString,
     io,
-    os::unix::io::{AsRawFd, RawFd},
+    os::fd::{AsRawFd, IntoRawFd as _, RawFd},
     path::{Path, PathBuf},
 };
 use thiserror::Error;
@@ -955,7 +955,7 @@ impl ProgramInfo {
                 call: "bpf_prog_get_fd_by_id",
                 io_error,
             })?;
-        Ok(fd as RawFd)
+        Ok(fd.into_raw_fd())
     }
 
     /// Loads a program from a pinned path in bpffs.
@@ -1003,14 +1003,12 @@ impl Iterator for ProgramsIter {
                             io_error,
                         })
                         .and_then(|fd| {
-                            let info = bpf_prog_get_info_by_fd(fd)
+                            bpf_prog_get_info_by_fd(fd.as_raw_fd())
                                 .map_err(|io_error| ProgramError::SyscallError {
                                     call: "bpf_prog_get_info_by_fd",
                                     io_error,
                                 })
-                                .map(ProgramInfo);
-                            unsafe { libc::close(fd) };
-                            info
+                                .map(ProgramInfo)
                         }),
                 )
             }

aya/src/sys/bpf.rs

@@ -3,7 +3,7 @@ use std::{
     ffi::{CStr, CString},
     io,
     mem::{self, MaybeUninit},
-    os::unix::io::RawFd,
+    os::fd::{FromRawFd as _, OwnedFd, RawFd},
     slice,
 };
 
@@ -460,13 +460,23 @@ pub(crate) fn bpf_prog_query(
     ret
 }
 
-pub(crate) fn bpf_prog_get_fd_by_id(prog_id: u32) -> Result<RawFd, io::Error> {
+pub(crate) fn bpf_prog_get_fd_by_id(prog_id: u32) -> Result<OwnedFd, io::Error> {
     let mut attr = unsafe { mem::zeroed::<bpf_attr>() };
 
     attr.__bindgen_anon_6.__bindgen_anon_1.prog_id = prog_id;
 
     match sys_bpf(bpf_cmd::BPF_PROG_GET_FD_BY_ID, &attr) {
-        Ok(v) => Ok(v as RawFd),
+        Ok(v) => {
+            let v = v.try_into().map_err(|_err| {
+                // _err is std::num::TryFromIntError or std::convert::Infallible depending on
+                // target, so we can't ascribe.
+                io::Error::new(
+                    io::ErrorKind::InvalidData,
+                    format!("bpf_prog_get_fd_by_id: invalid fd returned: {}", v),
+                )
+            })?;
+            Ok(unsafe { OwnedFd::from_raw_fd(v) })
+        }
         Err((_, err)) => Err(err),
     }
 }