Fix invalid memory access attempting to read the compression header of a too-small compressed section.

PR binutils/21149
	* readelf.c (get_compression_header): Add size parameter.  Check
	size against sizeof compression header before attempting to
	extract the header.
	(process_section_headers): Pass size to get_compression_header.
	(dump_section_as_strings): Likewise.
	(dump_section_as_bytes): Likewise.
	(load_specific_debug_section): Likewise.
This commit is contained in:
Nick Clifton 2017-02-13 14:52:48 +00:00
parent 4aeb00ad3c
commit ebdf1ebfa5
2 changed files with 29 additions and 5 deletions

View File

@ -1,3 +1,14 @@
2017-02-13 Nick Clifton <nickc@redhat.com>
PR binutils/21149
* readelf.c (get_compression_header): Add size parameter. Check
size against sizeof compression header before attempting to
extract the header.
(process_section_headers): Pass size to get_compression_header.
(dump_section_as_strings): Likewise.
(dump_section_as_bytes): Likewise.
(load_specific_debug_section): Likewise.
2017-02-13 Nick Clifton <nickc@redhat.com>
PR binutils/21148

View File

@ -5715,12 +5715,18 @@ get_elf_section_flags (bfd_vma sh_flags)
}
static unsigned int
get_compression_header (Elf_Internal_Chdr *chdr, unsigned char *buf)
get_compression_header (Elf_Internal_Chdr *chdr, unsigned char *buf, bfd_size_type size)
{
if (is_32bit_elf)
{
Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) buf;
if (size < sizeof (* echdr))
{
error (_("Compressed section is too small even for a compression header\n"));
return 0;
}
chdr->ch_type = BYTE_GET (echdr->ch_type);
chdr->ch_size = BYTE_GET (echdr->ch_size);
chdr->ch_addralign = BYTE_GET (echdr->ch_addralign);
@ -5730,6 +5736,12 @@ get_compression_header (Elf_Internal_Chdr *chdr, unsigned char *buf)
{
Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) buf;
if (size < sizeof (* echdr))
{
error (_("Compressed section is too small even for a compression header\n"));
return 0;
}
chdr->ch_type = BYTE_GET (echdr->ch_type);
chdr->ch_size = BYTE_GET (echdr->ch_size);
chdr->ch_addralign = BYTE_GET (echdr->ch_addralign);
@ -6311,7 +6323,7 @@ process_section_headers (FILE * file)
{
Elf_Internal_Chdr chdr;
(void) get_compression_header (&chdr, buf);
(void) get_compression_header (&chdr, buf, sizeof (buf));
if (chdr.ch_type == ELFCOMPRESS_ZLIB)
printf (" ZLIB, ");
@ -12643,7 +12655,8 @@ dump_section_as_strings (Elf_Internal_Shdr * section, FILE * file)
{
Elf_Internal_Chdr chdr;
unsigned int compression_header_size
= get_compression_header (& chdr, (unsigned char *) start);
= get_compression_header (& chdr, (unsigned char *) start,
num_bytes);
if (chdr.ch_type != ELFCOMPRESS_ZLIB)
{
@ -12777,7 +12790,7 @@ dump_section_as_bytes (Elf_Internal_Shdr * section,
{
Elf_Internal_Chdr chdr;
unsigned int compression_header_size
= get_compression_header (& chdr, start);
= get_compression_header (& chdr, start, section_size);
if (chdr.ch_type != ELFCOMPRESS_ZLIB)
{
@ -12930,7 +12943,7 @@ load_specific_debug_section (enum dwarf_section_display_enum debug,
return 0;
}
compression_header_size = get_compression_header (&chdr, start);
compression_header_size = get_compression_header (&chdr, start, size);
if (chdr.ch_type != ELFCOMPRESS_ZLIB)
{