/* Compressed section support (intended for debug sections).
- Copyright (C) 2008-2022 Free Software Foundation, Inc.
+ Copyright (C) 2008-2023 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
#include "elf-bfd.h"
#include "libbfd.h"
#include "safe-ctype.h"
+#include "libiberty.h"
#define MAX_COMPRESSION_HEADER_SIZE 24
/*
CODE_FRAGMENT
+.{* Types of compressed DWARF debug sections. *}
+.enum compressed_debug_section_type
+.{
+. COMPRESS_DEBUG_NONE = 0,
+. COMPRESS_DEBUG_GNU_ZLIB = 1 << 1,
+. COMPRESS_DEBUG_GABI_ZLIB = 1 << 2,
+. COMPRESS_DEBUG_ZSTD = 1 << 3,
+. COMPRESS_UNKNOWN = 1 << 4
+.};
+.
+.{* Tuple for compressed_debug_section_type and their name. *}
+.struct compressed_type_tuple
+.{
+. enum compressed_debug_section_type type;
+. const char *name;
+.};
+.
+.{* Compression header ch_type values. *}
+.enum compression_type
+.{
+. ch_none = 0,
+. ch_compress_zlib = 1 , {* Compressed with zlib. *}
+. ch_compress_zstd = 2 {* Compressed with zstd (www.zstandard.org). *}
+.};
+.
.static inline char *
.bfd_debug_name_to_zdebug (bfd *abfd, const char *name)
.{
.
*/
+/* Display texts for type of compressed DWARF debug sections. */
+static const struct compressed_type_tuple compressed_debug_section_names[] =
+{
+ { COMPRESS_DEBUG_NONE, "none" },
+ { COMPRESS_DEBUG_GABI_ZLIB, "zlib" },
+ { COMPRESS_DEBUG_GNU_ZLIB, "zlib-gnu" },
+ { COMPRESS_DEBUG_GABI_ZLIB, "zlib-gabi" },
+ { COMPRESS_DEBUG_ZSTD, "zstd" },
+};
+
+/*
+FUNCTION
+ bfd_get_compression_algorithm
+SYNOPSIS
+ enum compressed_debug_section_type
+ bfd_get_compression_algorithm (const char *name);
+DESCRIPTION
+ Return compressed_debug_section_type from a string representation.
+*/
+enum compressed_debug_section_type
+bfd_get_compression_algorithm (const char *name)
+{
+ for (unsigned i = 0; i < ARRAY_SIZE (compressed_debug_section_names); ++i)
+ if (strcasecmp (compressed_debug_section_names[i].name, name) == 0)
+ return compressed_debug_section_names[i].type;
+
+ return COMPRESS_UNKNOWN;
+}
+
+/*
+FUNCTION
+ bfd_get_compression_algorithm_name
+SYNOPSIS
+ const char *bfd_get_compression_algorithm_name
+ (enum compressed_debug_section_type type);
+DESCRIPTION
+ Return compression algorithm name based on the type.
+*/
+const char *
+bfd_get_compression_algorithm_name (enum compressed_debug_section_type type)
+{
+ for (unsigned i = 0; i < ARRAY_SIZE (compressed_debug_section_names); ++i)
+ if (type == compressed_debug_section_names[i].type)
+ return compressed_debug_section_names[i].name;
+
+ return NULL;
+}
+
+/*
+FUNCTION
+ bfd_update_compression_header
+
+SYNOPSIS
+ void bfd_update_compression_header
+ (bfd *abfd, bfd_byte *contents, asection *sec);
+
+DESCRIPTION
+ Set the compression header at CONTENTS of SEC in ABFD and update
+ elf_section_flags for compression.
+*/
+
+void
+bfd_update_compression_header (bfd *abfd, bfd_byte *contents,
+ asection *sec)
+{
+ if ((abfd->flags & BFD_COMPRESS) == 0)
+ abort ();
+
+ switch (bfd_get_flavour (abfd))
+ {
+ case bfd_target_elf_flavour:
+ if ((abfd->flags & BFD_COMPRESS_GABI) != 0)
+ {
+ const struct elf_backend_data *bed = get_elf_backend_data (abfd);
+ struct bfd_elf_section_data * esd = elf_section_data (sec);
+ enum compression_type ch_type = (abfd->flags & BFD_COMPRESS_ZSTD
+ ? ch_compress_zstd
+ : ch_compress_zlib);
+
+ /* Set the SHF_COMPRESSED bit. */
+ elf_section_flags (sec) |= SHF_COMPRESSED;
+
+ if (bed->s->elfclass == ELFCLASS32)
+ {
+ Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) contents;
+ bfd_put_32 (abfd, ch_type, &echdr->ch_type);
+ bfd_put_32 (abfd, sec->size, &echdr->ch_size);
+ bfd_put_32 (abfd, 1u << sec->alignment_power,
+ &echdr->ch_addralign);
+ /* bfd_log2 (alignof (Elf32_Chdr)) */
+ bfd_set_section_alignment (sec, 2);
+ esd->this_hdr.sh_addralign = 4;
+ }
+ else
+ {
+ Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) contents;
+ bfd_put_32 (abfd, ch_type, &echdr->ch_type);
+ bfd_put_32 (abfd, 0, &echdr->ch_reserved);
+ bfd_put_64 (abfd, sec->size, &echdr->ch_size);
+ bfd_put_64 (abfd, UINT64_C (1) << sec->alignment_power,
+ &echdr->ch_addralign);
+ /* bfd_log2 (alignof (Elf64_Chdr)) */
+ bfd_set_section_alignment (sec, 3);
+ esd->this_hdr.sh_addralign = 8;
+ }
+ break;
+ }
+
+ /* Clear the SHF_COMPRESSED bit. */
+ elf_section_flags (sec) &= ~SHF_COMPRESSED;
+ /* Fall through. */
+
+ default:
+ /* Write the zlib header. It should be "ZLIB" followed by
+ the uncompressed section size, 8 bytes in big-endian
+ order. */
+ memcpy (contents, "ZLIB", 4);
+ bfd_putb64 (sec->size, contents + 4);
+ /* No way to keep the original alignment, just use 1 always. */
+ bfd_set_section_alignment (sec, 0);
+ break;
+ }
+}
+
+/* Check the compression header at CONTENTS of SEC in ABFD and store the
+ ch_type in CH_TYPE, uncompressed size in UNCOMPRESSED_SIZE, and the
+ uncompressed data alignment in UNCOMPRESSED_ALIGNMENT_POWER if the
+ compression header is valid. */
+
+static bool
+bfd_check_compression_header (bfd *abfd, bfd_byte *contents,
+ asection *sec,
+ enum compression_type *ch_type,
+ bfd_size_type *uncompressed_size,
+ unsigned int *uncompressed_alignment_power)
+{
+ if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
+ && (elf_section_flags (sec) & SHF_COMPRESSED) != 0)
+ {
+ Elf_Internal_Chdr chdr;
+ const struct elf_backend_data *bed = get_elf_backend_data (abfd);
+ if (bed->s->elfclass == ELFCLASS32)
+ {
+ Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) contents;
+ chdr.ch_type = bfd_get_32 (abfd, &echdr->ch_type);
+ chdr.ch_size = bfd_get_32 (abfd, &echdr->ch_size);
+ chdr.ch_addralign = bfd_get_32 (abfd, &echdr->ch_addralign);
+ }
+ else
+ {
+ Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) contents;
+ chdr.ch_type = bfd_get_32 (abfd, &echdr->ch_type);
+ chdr.ch_size = bfd_get_64 (abfd, &echdr->ch_size);
+ chdr.ch_addralign = bfd_get_64 (abfd, &echdr->ch_addralign);
+ }
+ *ch_type = chdr.ch_type;
+ if ((chdr.ch_type == ch_compress_zlib
+ || chdr.ch_type == ch_compress_zstd)
+ && chdr.ch_addralign == (chdr.ch_addralign & -chdr.ch_addralign))
+ {
+ *uncompressed_size = chdr.ch_size;
+ *uncompressed_alignment_power = bfd_log2 (chdr.ch_addralign);
+ return true;
+ }
+ }
+
+ return false;
+}
+
+/*
+FUNCTION
+ bfd_get_compression_header_size
+
+SYNOPSIS
+ int bfd_get_compression_header_size (bfd *abfd, asection *sec);
+
+DESCRIPTION
+ Return the size of the compression header of SEC in ABFD.
+*/
+
+int
+bfd_get_compression_header_size (bfd *abfd, asection *sec)
+{
+ if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
+ {
+ if (sec == NULL)
+ {
+ if (!(abfd->flags & BFD_COMPRESS_GABI))
+ return 0;
+ }
+ else if (!(elf_section_flags (sec) & SHF_COMPRESSED))
+ return 0;
+
+ if (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS32)
+ return sizeof (Elf32_External_Chdr);
+ else
+ return sizeof (Elf64_External_Chdr);
+ }
+
+ return 0;
+}
+
+/*
+FUNCTION
+ bfd_convert_section_setup
+
+SYNOPSIS
+ bool bfd_convert_section_setup
+ (bfd *ibfd, asection *isec, bfd *obfd,
+ const char **new_name, bfd_size_type *new_size);
+
+DESCRIPTION
+ Do early setup for objcopy, when copying @var{isec} in input
+ BFD @var{ibfd} to output BFD @var{obfd}. Returns the name and
+ size of the output section.
+*/
+
+bool
+bfd_convert_section_setup (bfd *ibfd, asection *isec, bfd *obfd,
+ const char **new_name, bfd_size_type *new_size)
+{
+ bfd_size_type hdr_size;
+
+ if ((isec->flags & SEC_DEBUGGING) != 0
+ && (isec->flags & SEC_HAS_CONTENTS) != 0)
+ {
+ const char *name = *new_name;
+
+ if ((obfd->flags & (BFD_DECOMPRESS | BFD_COMPRESS_GABI)) != 0)
+ {
+ /* When we decompress or compress with SHF_COMPRESSED,
+ convert section name from .zdebug_* to .debug_*. */
+ if (startswith (name, ".zdebug_"))
+ {
+ name = bfd_zdebug_name_to_debug (obfd, name);
+ if (name == NULL)
+ return false;
+ }
+ }
+
+ /* PR binutils/18087: Compression does not always make a
+ section smaller. So only rename the section when
+ compression has actually taken place. If input section
+ name is .zdebug_*, we should never compress it again. */
+ else if (isec->compress_status == COMPRESS_SECTION_DONE
+ && startswith (name, ".debug_"))
+ {
+ name = bfd_debug_name_to_zdebug (obfd, name);
+ if (name == NULL)
+ return false;
+ }
+ *new_name = name;
+ }
+ *new_size = bfd_section_size (isec);
+
+ /* Do nothing if either input or output aren't ELF. */
+ if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
+ || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
+ return true;
+
+ /* Do nothing if ELF classes of input and output are the same. */
+ if (get_elf_backend_data (ibfd)->s->elfclass
+ == get_elf_backend_data (obfd)->s->elfclass)
+ return true;
+
+ /* Convert GNU property size. */
+ if (startswith (isec->name, NOTE_GNU_PROPERTY_SECTION_NAME))
+ {
+ *new_size = _bfd_elf_convert_gnu_property_size (ibfd, obfd);
+ return true;
+ }
+
+ /* Do nothing if input file will be decompressed. */
+ if ((ibfd->flags & BFD_DECOMPRESS))
+ return true;
+
+ /* Do nothing if the input section isn't a SHF_COMPRESSED section. */
+ hdr_size = bfd_get_compression_header_size (ibfd, isec);
+ if (hdr_size == 0)
+ return true;
+
+ /* Adjust the size of the output SHF_COMPRESSED section. */
+ if (hdr_size == sizeof (Elf32_External_Chdr))
+ *new_size += sizeof (Elf64_External_Chdr) - sizeof (Elf32_External_Chdr);
+ else
+ *new_size -= sizeof (Elf64_External_Chdr) - sizeof (Elf32_External_Chdr);
+ return true;
+}
+
+/*
+FUNCTION
+ bfd_convert_section_contents
+
+SYNOPSIS
+ bool bfd_convert_section_contents
+ (bfd *ibfd, asection *isec, bfd *obfd,
+ bfd_byte **ptr, bfd_size_type *ptr_size);
+
+DESCRIPTION
+ Convert the contents, stored in @var{*ptr}, of the section
+ @var{isec} in input BFD @var{ibfd} to output BFD @var{obfd}
+ if needed. The original buffer pointed to by @var{*ptr} may
+ be freed and @var{*ptr} is returned with memory malloc'd by this
+ function, and the new size written to @var{ptr_size}.
+*/
+
+bool
+bfd_convert_section_contents (bfd *ibfd, sec_ptr isec, bfd *obfd,
+ bfd_byte **ptr, bfd_size_type *ptr_size)
+{
+ bfd_byte *contents;
+ bfd_size_type ihdr_size, ohdr_size, size;
+ Elf_Internal_Chdr chdr;
+ bool use_memmove;
+
+ /* Do nothing if either input or output aren't ELF. */
+ if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
+ || bfd_get_flavour (obfd) != bfd_target_elf_flavour)
+ return true;
+
+ /* Do nothing if ELF classes of input and output are the same. */
+ if (get_elf_backend_data (ibfd)->s->elfclass
+ == get_elf_backend_data (obfd)->s->elfclass)
+ return true;
+
+ /* Convert GNU properties. */
+ if (startswith (isec->name, NOTE_GNU_PROPERTY_SECTION_NAME))
+ return _bfd_elf_convert_gnu_properties (ibfd, isec, obfd, ptr,
+ ptr_size);
+
+ /* Do nothing if input file will be decompressed. */
+ if ((ibfd->flags & BFD_DECOMPRESS))
+ return true;
+
+ /* Do nothing if the input section isn't a SHF_COMPRESSED section. */
+ ihdr_size = bfd_get_compression_header_size (ibfd, isec);
+ if (ihdr_size == 0)
+ return true;
+
+ /* PR 25221. Check for corrupt input sections. */
+ if (ihdr_size > bfd_get_section_limit (ibfd, isec))
+ /* FIXME: Issue a warning about a corrupt
+ compression header size field ? */
+ return false;
+
+ contents = *ptr;
+
+ /* Convert the contents of the input SHF_COMPRESSED section to
+ output. Get the input compression header and the size of the
+ output compression header. */
+ if (ihdr_size == sizeof (Elf32_External_Chdr))
+ {
+ Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) contents;
+ chdr.ch_type = bfd_get_32 (ibfd, &echdr->ch_type);
+ chdr.ch_size = bfd_get_32 (ibfd, &echdr->ch_size);
+ chdr.ch_addralign = bfd_get_32 (ibfd, &echdr->ch_addralign);
+
+ ohdr_size = sizeof (Elf64_External_Chdr);
+
+ use_memmove = false;
+ }
+ else if (ihdr_size != sizeof (Elf64_External_Chdr))
+ {
+ /* FIXME: Issue a warning about a corrupt
+ compression header size field ? */
+ return false;
+ }
+ else
+ {
+ Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) contents;
+ chdr.ch_type = bfd_get_32 (ibfd, &echdr->ch_type);
+ chdr.ch_size = bfd_get_64 (ibfd, &echdr->ch_size);
+ chdr.ch_addralign = bfd_get_64 (ibfd, &echdr->ch_addralign);
+
+ ohdr_size = sizeof (Elf32_External_Chdr);
+ use_memmove = true;
+ }
+
+ size = bfd_section_size (isec) - ihdr_size + ohdr_size;
+ if (!use_memmove)
+ {
+ contents = (bfd_byte *) bfd_malloc (size);
+ if (contents == NULL)
+ return false;
+ }
+
+ /* Write out the output compression header. */
+ if (ohdr_size == sizeof (Elf32_External_Chdr))
+ {
+ Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) contents;
+ bfd_put_32 (obfd, chdr.ch_type, &echdr->ch_type);
+ bfd_put_32 (obfd, chdr.ch_size, &echdr->ch_size);
+ bfd_put_32 (obfd, chdr.ch_addralign, &echdr->ch_addralign);
+ }
+ else
+ {
+ Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) contents;
+ bfd_put_32 (obfd, chdr.ch_type, &echdr->ch_type);
+ bfd_put_32 (obfd, 0, &echdr->ch_reserved);
+ bfd_put_64 (obfd, chdr.ch_size, &echdr->ch_size);
+ bfd_put_64 (obfd, chdr.ch_addralign, &echdr->ch_addralign);
+ }
+
+ /* Copy the compressed contents. */
+ if (use_memmove)
+ memmove (contents + ohdr_size, *ptr + ihdr_size, size - ohdr_size);
+ else
+ {
+ memcpy (contents + ohdr_size, *ptr + ihdr_size, size - ohdr_size);
+ free (*ptr);
+ *ptr = contents;
+ }
+
+ *ptr_size = size;
+ return true;
+}
+
static bool
decompress_contents (bool is_zstd, bfd_byte *compressed_buffer,
bfd_size_type compressed_size,
int orig_header_size;
bfd_size_type uncompressed_size;
unsigned int uncompressed_alignment_pow;
- unsigned int ch_type = 0;
+ enum compression_type ch_type = ch_none;
int new_header_size = bfd_get_compression_header_size (abfd, NULL);
bool compressed
= bfd_is_section_compressed_info (abfd, sec,
overhead in .zdebug* section. */
if (!new_header_size)
new_header_size = 12;
- if (ch_type == 0)
+ if (ch_type == ch_none)
orig_header_size = 12;
input_buffer = sec->contents;
/* If we are converting between zlib-gnu and zlib-gabi then the
compressed contents just need to be moved. */
- update = (ch_type < ELFCOMPRESS_ZSTD
+ update = (ch_type < ch_compress_zstd
&& (abfd->flags & BFD_COMPRESS_ZSTD) == 0);
/* Uncompress when not just moving contents or when compressed
if (buffer == NULL)
return 0;
- if (!decompress_contents (ch_type == ELFCOMPRESS_ZSTD,
+ if (!decompress_contents (ch_type == ch_compress_zstd,
input_buffer + orig_header_size,
zlib_size, buffer, buffer_size))
{
if (compressed_size >= uncompressed_size)
{
memcpy (buffer, input_buffer, uncompressed_size);
- elf_section_flags (sec) &= ~SHF_COMPRESSED;
+ if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
+ elf_section_flags (sec) &= ~SHF_COMPRESSED;
sec->compress_status = COMPRESS_SECTION_NONE;
}
else
bool
bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
{
- bfd_size_type sz = bfd_get_section_limit_octets (abfd, sec);
+ bfd_size_type readsz = bfd_get_section_limit_octets (abfd, sec);
+ bfd_size_type allocsz = bfd_get_section_alloc_size (abfd, sec);
bfd_byte *p = *ptr;
bool ret;
bfd_size_type save_size;
unsigned int compression_header_size;
const unsigned int compress_status = sec->compress_status;
- if (sz == 0)
+ if (allocsz == 0)
{
*ptr = NULL;
return true;
_bfd_error_handler
/* xgettext:c-format */
(_("error: %pB(%pA) is too large (%#" PRIx64 " bytes)"),
- abfd, sec, (uint64_t) sz);
+ abfd, sec, (uint64_t) readsz);
return false;
}
case COMPRESS_SECTION_NONE:
if (p == NULL)
{
- p = (bfd_byte *) bfd_malloc (sz);
+ p = (bfd_byte *) bfd_malloc (allocsz);
if (p == NULL)
{
/* PR 20801: Provide a more helpful error message. */
_bfd_error_handler
/* xgettext:c-format */
(_("error: %pB(%pA) is too large (%#" PRIx64 " bytes)"),
- abfd, sec, (uint64_t) sz);
+ abfd, sec, (uint64_t) allocsz);
return false;
}
}
- if (!bfd_get_section_contents (abfd, sec, p, 0, sz))
+ if (!bfd_get_section_contents (abfd, sec, p, 0, readsz))
{
if (*ptr != p)
free (p);
goto fail_compressed;
if (p == NULL)
- p = (bfd_byte *) bfd_malloc (sz);
+ p = (bfd_byte *) bfd_malloc (allocsz);
if (p == NULL)
goto fail_compressed;
bool is_zstd = compress_status == DECOMPRESS_SECTION_ZSTD;
if (!decompress_contents (
is_zstd, compressed_buffer + compression_header_size,
- sec->compressed_size - compression_header_size, p, sz))
+ sec->compressed_size - compression_header_size, p, readsz))
{
bfd_set_error (bfd_error_bad_value);
if (p != *ptr)
return false;
if (p == NULL)
{
- p = (bfd_byte *) bfd_malloc (sz);
+ p = (bfd_byte *) bfd_malloc (allocsz);
if (p == NULL)
return false;
*ptr = p;
}
/* PR 17512; file: 5bc29788. */
if (p != sec->contents)
- memcpy (p, sec->contents, sz);
+ memcpy (p, sec->contents, readsz);
return true;
default:
int *compression_header_size_p,
bfd_size_type *uncompressed_size_p,
unsigned int *uncompressed_alignment_power_p,
- unsigned int *ch_type);
+ enum compression_type *ch_type);
DESCRIPTION
Return @code{TRUE} if @var{section} is compressed. Compression
int *compression_header_size_p,
bfd_size_type *uncompressed_size_p,
unsigned int *uncompressed_align_pow_p,
- unsigned int *ch_type)
+ enum compression_type *ch_type)
{
bfd_byte header[MAX_COMPRESSION_HEADER_SIZE];
int compression_header_size;
int compression_header_size;
bfd_size_type uncompressed_size;
unsigned int uncompressed_align_power;
- unsigned int ch_type;
+ enum compression_type ch_type;
return (bfd_is_section_compressed_info (abfd, sec,
&compression_header_size,
&uncompressed_size,
int header_size;
bfd_size_type uncompressed_size;
unsigned int uncompressed_alignment_power = 0;
- unsigned int ch_type;
+ enum compression_type ch_type;
z_stream strm;
compression_header_size = bfd_get_compression_header_size (abfd, sec);
return false;
}
uncompressed_size = bfd_getb64 (header + 4);
- ch_type = 0;
+ ch_type = ch_none;
}
else if (!bfd_check_compression_header (abfd, header, sec,
&ch_type,
sec->compressed_size = sec->size;
sec->size = uncompressed_size;
bfd_set_section_alignment (sec, uncompressed_alignment_power);
- sec->compress_status = (ch_type == ELFCOMPRESS_ZSTD
+ sec->compress_status = (ch_type == ch_compress_zstd
? DECOMPRESS_SECTION_ZSTD : DECOMPRESS_SECTION_ZLIB);
return true;
|| sec->size == 0
|| sec->rawsize != 0
|| sec->contents != NULL
- || sec->compress_status != COMPRESS_SECTION_NONE)
+ || sec->compress_status != COMPRESS_SECTION_NONE
+ || _bfd_section_size_insane (abfd, sec))
{
bfd_set_error (bfd_error_invalid_operation);
return false;
if (!bfd_get_section_contents (abfd, sec, uncompressed_buffer,
0, uncompressed_size))
- return false;
+ {
+ free (uncompressed_buffer);
+ return false;
+ }
sec->contents = uncompressed_buffer;
if (bfd_compress_section_contents (abfd, sec) == 0)