diff --git a/compiler/rustc_codegen_ssa/src/back/metadata.rs b/compiler/rustc_codegen_ssa/src/back/metadata.rs index d5d843702c003..baf674cf9eba6 100644 --- a/compiler/rustc_codegen_ssa/src/back/metadata.rs +++ b/compiler/rustc_codegen_ssa/src/back/metadata.rs @@ -12,6 +12,7 @@ use object::{ use snap::write::FrameEncoder; +use object::elf::NT_GNU_PROPERTY_TYPE_0; use rustc_data_structures::memmap::Mmap; use rustc_data_structures::owned_slice::try_slice_owned; use rustc_data_structures::sync::MetadataRef; @@ -93,6 +94,46 @@ pub(super) fn search_for_section<'a>( .map_err(|e| format!("failed to read {} section in '{}': {}", section, path.display(), e)) } +fn add_gnu_property_note( + file: &mut write::Object<'static>, + architecture: Architecture, + binary_format: BinaryFormat, +) { + // check bti protection + if binary_format != BinaryFormat::Elf + || !matches!(architecture, Architecture::X86_64 | Architecture::Aarch64) + { + return; + } + + let section = file.add_section( + file.segment_name(StandardSegment::Data).to_vec(), + b".note.gnu.property".to_vec(), + SectionKind::Note, + ); + let mut data: Vec = Vec::new(); + let n_namsz: u32 = 4; // Size of the n_name field + let n_descsz: u32 = 16; // Size of the n_desc field + let n_type: u32 = NT_GNU_PROPERTY_TYPE_0; // Type of note descriptor + let values = [n_namsz, n_descsz, n_type]; + values.map(|v| data.extend_from_slice(&(v.to_le_bytes()))); + data.push(b'G'); // Owner of the program property note + data.push(b'N'); + data.push(b'U'); + data.push(0); + let pr_type: u32 = match architecture { + Architecture::X86_64 => 0xc0000002, + Architecture::Aarch64 => 0xc0000000, + _ => unreachable!(), + }; + let pr_datasz: u32 = 4; //size of the pr_data field + let pr_data: u32 = 3; //program property descriptor + let pr_padding: u32 = 3; + let values = [pr_type, pr_datasz, pr_data, pr_padding]; + values.map(|v| data.extend_from_slice(&(v.to_le_bytes()))); + file.append_section_data(section, &data, 4); +} + pub(crate) fn create_object_file(sess: &Session) -> Option> { let endianness = match sess.target.options.endian { Endian::Little => Endianness::Little, @@ -205,6 +246,7 @@ pub(crate) fn create_object_file(sess: &Session) -> Option elf::ELFOSABI_NONE, }; let abi_version = 0; + add_gnu_property_note(&mut file, architecture, binary_format); file.flags = FileFlags::Elf { os_abi, abi_version, e_flags }; Some(file) }