From 0b69c59656f564d1aa68ec6b5c1b0be55475a864 Mon Sep 17 00:00:00 2001 From: Alex Brachet Date: Fri, 6 Sep 2019 02:27:55 +0000 Subject: [PATCH] [yaml2obj] Make e_phoff and e_phentsize 0 if there are no program headers Summary: It says [[ http://www.sco.com/developers/gabi/latest/ch4.eheader.html | here ]] that if there are no program headers than e_phoff should be 0, but currently it is always set after the header. GNU's `readelf` (but not `llvm-readelf`) complains about this: `readelf: Warning: possibly corrupt ELF header - it has a non-zero program header offset, but no program headers`. Reviewers: jhenderson, grimar, MaskRay, rupprecht Reviewed By: jhenderson, grimar, MaskRay Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D67054 llvm-svn: 371162 --- llvm/lib/ObjectYAML/ELFEmitter.cpp | 4 ++-- llvm/test/tools/yaml2obj/elf-no-phdrs.yaml | 15 +++++++++++++++ 2 files changed, 17 insertions(+), 2 deletions(-) create mode 100644 llvm/test/tools/yaml2obj/elf-no-phdrs.yaml diff --git a/llvm/lib/ObjectYAML/ELFEmitter.cpp b/llvm/lib/ObjectYAML/ELFEmitter.cpp index 362a943..e3dcd8c 100644 --- a/llvm/lib/ObjectYAML/ELFEmitter.cpp +++ b/llvm/lib/ObjectYAML/ELFEmitter.cpp @@ -224,10 +224,10 @@ void ELFState::writeELFHeader(ContiguousBlobAccumulator &CBA, raw_ostream Header.e_machine = Doc.Header.Machine; Header.e_version = EV_CURRENT; Header.e_entry = Doc.Header.Entry; - Header.e_phoff = sizeof(Header); + Header.e_phoff = Doc.ProgramHeaders.size() ? sizeof(Header) : 0; Header.e_flags = Doc.Header.Flags; Header.e_ehsize = sizeof(Elf_Ehdr); - Header.e_phentsize = sizeof(Elf_Phdr); + Header.e_phentsize = Doc.ProgramHeaders.size() ? sizeof(Elf_Phdr) : 0; Header.e_phnum = Doc.ProgramHeaders.size(); Header.e_shentsize = diff --git a/llvm/test/tools/yaml2obj/elf-no-phdrs.yaml b/llvm/test/tools/yaml2obj/elf-no-phdrs.yaml new file mode 100644 index 0000000..e056b80 --- /dev/null +++ b/llvm/test/tools/yaml2obj/elf-no-phdrs.yaml @@ -0,0 +1,15 @@ +## Check that e_phoff and e_phentsize are set to 0 when there are no +## program headers. + +# RUN: yaml2obj %s -o %t +# RUN: llvm-readobj --file-headers %t | FileCheck %s + +# CHECK: ProgramHeaderOffset: 0x0{{$}} +# CHECK: ProgramHeaderEntrySize: 0{{$}} + +--- !ELF +FileHeader: + Class: ELFCLASS64 + Data: ELFDATA2LSB + Type: ET_REL + Machine: EM_X86_64 -- 2.7.4