From dd68a12bc4b19c50c31fe357335bb8ee9a3322fc Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Tue, 19 Nov 2019 14:53:44 +1030 Subject: [PATCH] PR25191, internal error in _bfd_elf_set_section_contents This PR copies a fuzzed PE input file to ELF output, in the process confusing the ELF backend by copying COFF-only section flags to the output. SEC_COFF_SHARED has the same value as SEC_ELF_COMPRESS. One approach to fixing this problem is of course not to reuse flag bits, but we've run out. So this patch only copies section flags that are in the bfd_applicable_section_flags set when changing the flavour of the output file. PR 25191 * objcopy.c (is_nondebug_keep_contents_section): Use bfd_get_flavour. (copy_object): Likewise. (setup_section): Likewise. If flavour of input and output files differ, restrict section flags to the intersection of input and output bfd_applicable_section_flags. --- binutils/ChangeLog | 9 +++++++++ binutils/objcopy.c | 25 +++++++++++++++---------- 2 files changed, 24 insertions(+), 10 deletions(-) diff --git a/binutils/ChangeLog b/binutils/ChangeLog index bf6d20e596e..4fabf0cb063 100644 --- a/binutils/ChangeLog +++ b/binutils/ChangeLog @@ -1,3 +1,12 @@ +2019-11-19 Alan Modra + + PR 25191 + * objcopy.c (is_nondebug_keep_contents_section): Use bfd_get_flavour. + (copy_object): Likewise. + (setup_section): Likewise. If flavour of input and output files + differ, restrict section flags to the intersection of input and + output bfd_applicable_section_flags. + 2019-11-19 Alan Modra * bucomm.c (bfd_nonfatal_message): Add a space between program diff --git a/binutils/objcopy.c b/binutils/objcopy.c index ea6eb646b4f..551378da399 100644 --- a/binutils/objcopy.c +++ b/binutils/objcopy.c @@ -1421,16 +1421,16 @@ static bfd_boolean is_nondebug_keep_contents_section (bfd *ibfd, asection *isection) { /* Always keep ELF note sections. */ - if (ibfd->xvec->flavour == bfd_target_elf_flavour) - return (elf_section_type (isection) == SHT_NOTE); + if (bfd_get_flavour (ibfd) == bfd_target_elf_flavour) + return elf_section_type (isection) == SHT_NOTE; /* Always keep the .buildid section for PE/COFF. Strictly, this should be written "always keep the section storing the debug directory", but that may be the .text section for objects produced by some tools, which it is not sensible to keep. */ - if (ibfd->xvec->flavour == bfd_target_coff_flavour) - return (strcmp (bfd_section_name (isection), ".buildid") == 0); + if (bfd_get_flavour (ibfd) == bfd_target_coff_flavour) + return strcmp (bfd_section_name (isection), ".buildid") == 0; return FALSE; } @@ -2585,7 +2585,7 @@ copy_object (bfd *ibfd, bfd *obfd, const bfd_arch_info_type *input_arch) return FALSE; } - if (ibfd->xvec->flavour != bfd_target_elf_flavour) + if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour) { if ((do_debug_sections & compress) != 0 && do_debug_sections != compress) @@ -2683,7 +2683,7 @@ copy_object (bfd *ibfd, bfd *obfd, const bfd_arch_info_type *input_arch) pe_data_type *pe = pe_data (obfd); /* Copy PE parameters before changing them. */ - if (ibfd->xvec->flavour == bfd_target_coff_flavour + if (bfd_get_flavour (ibfd) == bfd_target_coff_flavour && bfd_pei_p (ibfd)) pe->pe_opthdr = pe_data (ibfd)->pe_opthdr; @@ -3922,11 +3922,16 @@ setup_section (bfd *ibfd, sec_ptr isection, void *obfdarg) /* Get the, possibly new, name of the output section. */ name = bfd_section_name (isection); flags = bfd_section_flags (isection); + if (bfd_get_flavour (ibfd) != bfd_get_flavour (obfd)) + { + flags &= bfd_applicable_section_flags (ibfd); + flags &= bfd_applicable_section_flags (obfd); + } name = find_section_rename (name, &flags); /* Prefix sections. */ - if ((prefix_alloc_sections_string) - && (bfd_section_flags (isection) & SEC_ALLOC)) + if (prefix_alloc_sections_string + && (bfd_section_flags (isection) & SEC_ALLOC) != 0) prefix = prefix_alloc_sections_string; else if (prefix_sections_string) prefix = prefix_sections_string; @@ -3952,7 +3957,7 @@ setup_section (bfd *ibfd, sec_ptr isection, void *obfdarg) && !is_nondebug_keep_contents_section (ibfd, isection)) { flags &= ~(SEC_HAS_CONTENTS | SEC_LOAD | SEC_GROUP); - if (obfd->xvec->flavour == bfd_target_elf_flavour) + if (bfd_get_flavour (obfd) == bfd_target_elf_flavour) { make_nobits = TRUE; @@ -4055,7 +4060,7 @@ setup_section (bfd *ibfd, sec_ptr isection, void *obfdarg) if (gsym != NULL) { gsym->flags |= BSF_KEEP; - if (ibfd->xvec->flavour == bfd_target_elf_flavour) + if (bfd_get_flavour (ibfd) == bfd_target_elf_flavour) elf_group_id (isection) = gsym; } } -- 2.30.2