PR 33020 segv in _bfd_elf_strtab_offset

The PR fuzzer testcase creates a SHT_NOBITS .debug_info section, then
triggers a bug in --compress-debug-sections=zlib whereby sh_name is
set to -1 in elf_fake_sections as a flag to indicate the name is not
set yet (may change to zdebug_*), but the section never hits the debug
compression code in assign_file_positions_for_non_load_sections that
is responsible for setting sh_name.

	PR 33020
	* elf.c (_bfd_elf_init_reloc_shdr): Rename delay_st_name_p
	param to delay_sh_name_p.
	(elf_fake_sections): Rename delay_st_name_p to delay_sh_name_p.
	Don't set delay_sh_name_p for no contents debug sections.

diff --git a/bfd/elf.c b/bfd/elf.c
index 3073f860621f390dd5f6dabb8795bb8f6ec36c6f..5175d508d18f2ef961d3622ac94f30c7a2f3479d 100644 (file)
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -3469,7 +3469,7 @@ _bfd_elf_init_reloc_shdr (bfd *abfd,
                          struct bfd_elf_section_reloc_data *reldata,
                          const char *sec_name,
                          bool use_rela_p,
-                         bool delay_st_name_p)
+                         bool delay_sh_name_p)
 {
   Elf_Internal_Shdr *rel_hdr;
   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
@@ -3480,7 +3480,7 @@ _bfd_elf_init_reloc_shdr (bfd *abfd,
     return false;
   reldata->hdr = rel_hdr;
 
-  if (delay_st_name_p)
+  if (delay_sh_name_p)
     rel_hdr->sh_name = (unsigned int) -1;
   else if (!_bfd_elf_set_reloc_sh_name (abfd, rel_hdr, sec_name,
                                        use_rela_p))
@@ -3526,7 +3526,7 @@ elf_fake_sections (bfd *abfd, asection *asect, void *fsarg)
   Elf_Internal_Shdr *this_hdr;
   unsigned int sh_type;
   const char *name = asect->name;
-  bool delay_st_name_p = false;
+  bool delay_sh_name_p = false;
   bfd_vma mask;
 
   if (arg->failed)
@@ -3543,16 +3543,17 @@ elf_fake_sections (bfd *abfd, asection *asect, void *fsarg)
       && (abfd->flags & BFD_COMPRESS) != 0
       && (asect->flags & SEC_DEBUGGING) != 0
       && (asect->flags & SEC_ALLOC) == 0
+      && (asect->flags & SEC_HAS_CONTENTS) != 0
       && name[1] == 'd'
       && name[6] == '_')
     {
       /* If this section will be compressed, delay adding section
         name to section name section after it is compressed in
         _bfd_elf_assign_file_positions_for_non_load.  */
-      delay_st_name_p = true;
+      delay_sh_name_p = true;
     }
 
-  if (delay_st_name_p)
+  if (delay_sh_name_p)
     this_hdr->sh_name = (unsigned int) -1;
   else
     {
@@ -3751,14 +3752,14 @@ elf_fake_sections (bfd *abfd, asection *asect, void *fsarg)
        {
          if (esd->rel.count && esd->rel.hdr == NULL
              && !_bfd_elf_init_reloc_shdr (abfd, &esd->rel, name,
-                                           false, delay_st_name_p))
+                                           false, delay_sh_name_p))
            {
              arg->failed = true;
              return;
            }
          if (esd->rela.count && esd->rela.hdr == NULL
              && !_bfd_elf_init_reloc_shdr (abfd, &esd->rela, name,
-                                           true, delay_st_name_p))
+                                           true, delay_sh_name_p))
            {
              arg->failed = true;
              return;
@@ -3769,7 +3770,7 @@ elf_fake_sections (bfd *abfd, asection *asect, void *fsarg)
                                           ? &esd->rela : &esd->rel),
                                          name,
                                          asect->use_rela_p,
-                                         delay_st_name_p))
+                                         delay_sh_name_p))
        {
          arg->failed = true;
          return;