Fix: nm: SEGV on unknow address at nm.c:718 in print_symname

PR 30886 * elf-bfd.h (struct elf_obj_tdata): Add dt_strsz field.
  * elf.c (_bfd_elf_get_dynamic_symbols): Add a NUL byte at the end of the string table. Initialise the dt_strsz field. (_bfd_elf_slurp_version_tables): Only free the contents if they were malloc'ed. Add checks before setting string pointers in the dt_strtab buffer.
This commit is contained in:
Nick Clifton 2023-09-28 12:37:59 +01:00
parent 2654f77d14
commit 6136093c0d
3 changed files with 42 additions and 9 deletions

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@ -1,3 +1,14 @@
2023-09-28 Nick Clifton <nickc@redhat.com>
PR 30886
* elf-bfd.h (struct elf_obj_tdata): Add dt_strsz field.
* elf.c (_bfd_elf_get_dynamic_symbols): Add a NUL byte at the end
of the string table.
Initialise the dt_strsz field.
(_bfd_elf_slurp_version_tables): Only free the contents if they
were malloc'ed.
Add checks before setting string pointers in the dt_strtab buffer.
2023-09-27 Nick Clifton <nickc@redhat.com>
PR 30885

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@ -2039,7 +2039,8 @@ struct elf_obj_tdata
size_t dt_symtab_count;
size_t dt_verdef_count;
size_t dt_verneed_count;
char *dt_strtab;
char * dt_strtab;
size_t dt_strsz;
elf_section_list * symtab_shndx_list;
bfd_vma gp; /* The gp value */
unsigned int gp_size; /* The gp size */

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@ -2102,9 +2102,11 @@ _bfd_elf_get_dynamic_symbols (bfd *abfd, Elf_Internal_Phdr *phdr,
goto error_return;
/* Dynamic string table must be valid until ABFD is closed. */
strbuf = (char *) _bfd_alloc_and_read (abfd, dt_strsz, dt_strsz);
strbuf = (char *) _bfd_alloc_and_read (abfd, dt_strsz + 1, dt_strsz);
if (strbuf == NULL)
goto error_return;
/* Since this is a string table, make sure that it is terminated. */
strbuf[dt_strsz] = 0;
/* Get the real symbol count from DT_HASH or DT_GNU_HASH. Prefer
DT_HASH since it is simpler than DT_GNU_HASH. */
@ -2356,6 +2358,7 @@ _bfd_elf_get_dynamic_symbols (bfd *abfd, Elf_Internal_Phdr *phdr,
empty_gnu_hash:
elf_tdata (abfd)->dt_strtab = strbuf;
elf_tdata (abfd)->dt_strsz = dt_strsz;
elf_tdata (abfd)->dt_symtab = isymbuf;
elf_tdata (abfd)->dt_symtab_count = symcount;
elf_tdata (abfd)->dt_versym = versym;
@ -9396,6 +9399,7 @@ bool
_bfd_elf_slurp_version_tables (bfd *abfd, bool default_imported_symver)
{
bfd_byte *contents = NULL;
bool free_contents = false;
unsigned int freeidx = 0;
size_t amt;
@ -9438,6 +9442,7 @@ _bfd_elf_slurp_version_tables (bfd *abfd, bool default_imported_symver)
if (contents == NULL)
goto error_return_verref;
free_contents = true;
verneed_size = hdr->sh_size;
verneed_count = hdr->sh_info;
}
@ -9471,8 +9476,13 @@ _bfd_elf_slurp_version_tables (bfd *abfd, bool default_imported_symver)
iverneed->vn_bfd = abfd;
if (elf_use_dt_symtab_p (abfd))
iverneed->vn_filename
= elf_tdata (abfd)->dt_strtab + iverneed->vn_file;
{
if (iverneed->vn_file < elf_tdata (abfd)->dt_strsz)
iverneed->vn_filename
= elf_tdata (abfd)->dt_strtab + iverneed->vn_file;
else
iverneed->vn_filename = NULL;
}
else
iverneed->vn_filename
= bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
@ -9508,8 +9518,13 @@ _bfd_elf_slurp_version_tables (bfd *abfd, bool default_imported_symver)
_bfd_elf_swap_vernaux_in (abfd, evernaux, ivernaux);
if (elf_use_dt_symtab_p (abfd))
ivernaux->vna_nodename
= elf_tdata (abfd)->dt_strtab + ivernaux->vna_name;
{
if (ivernaux->vna_name < elf_tdata (abfd)->dt_strsz)
ivernaux->vna_nodename
= elf_tdata (abfd)->dt_strtab + ivernaux->vna_name;
else
ivernaux->vna_nodename = NULL;
}
else
ivernaux->vna_nodename
= bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
@ -9703,8 +9718,13 @@ _bfd_elf_slurp_version_tables (bfd *abfd, bool default_imported_symver)
_bfd_elf_swap_verdaux_in (abfd, everdaux, iverdaux);
if (elf_use_dt_symtab_p (abfd))
iverdaux->vda_nodename
= elf_tdata (abfd)->dt_strtab + iverdaux->vda_name;
{
if (iverdaux->vda_name < elf_tdata (abfd)->dt_strsz)
iverdaux->vda_nodename
= elf_tdata (abfd)->dt_strtab + iverdaux->vda_name;
else
iverdaux->vda_nodename = NULL;
}
else
iverdaux->vda_nodename
= bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
@ -9799,7 +9819,8 @@ _bfd_elf_slurp_version_tables (bfd *abfd, bool default_imported_symver)
return true;
error_return:
free (contents);
if (free_contents)
free (contents);
return false;
}