Handle ELF compressed header alignment correctly by setting up the section alignment correctly for the Elf32_Chdr or Elf64_Chdr type and respect the ch_addralign field when decompressing the section data.

	PR binutils/23919
binutils* readelf.c (dump_sections_as_strings): Remove bogus addralign check.
	(dump_sections_as_bytes): Likewise.
	(load_specific_debug_sections): Likewise.
	* testsuite/binutils-all/dw2-3.rS: Adjust alignment.
	* testsuite/binutils-all/dw2-3.rt: Likewise.

bfd	* bfd.c (bfd_update_compression_header): Explicitly set alignment.
	(bfd_check_compression_header): Add uncompressed_alignment_power
	argument. Check ch_addralign is a power of 2.
	* bfd-in2.h: Regenerated.
	* compress.c (bfd_compress_section_contents): Get and set
	orig_uncompressed_alignment_pow if section is decompressed.
	(bfd_is_section_compressed_with_header): Add and get
	uncompressed_align_pow_p argument.
	(bfd_is_section_compressed): Add uncompressed_align_power argument
	to bfd_is_section_compressed_with_header call.
	(bfd_init_section_decompress_status): Get and set
	uncompressed_alignment_power.
	* elf.c (_bfd_elf_make_section_from_shdr): Add
	uncompressed_align_power argument to
	bfd_is_section_compressed_with_header call.

1 files changed, 15 insertions, 5 deletions

diff --git a/bfd/bfd.c b/bfd/bfd.c
index 15becd7..2b65829 100644
--- a/bfd/bfd.c
+++ b/bfd/bfd.c
@@ -2332,6 +2332,8 @@ bfd_update_compression_header (bfd *abfd, bfd_byte *contents,
 		  bfd_put_32 (abfd, sec->size, &echdr->ch_size);
 		  bfd_put_32 (abfd, 1 << sec->alignment_power,
 			      &echdr->ch_addralign);
+		  /* bfd_log2 (alignof (Elf32_Chdr)) */
+		  bfd_set_section_alignment (abfd, sec, 2);
 		}
 	      else
 		{
@@ -2342,6 +2344,8 @@ bfd_update_compression_header (bfd *abfd, bfd_byte *contents,
 		  bfd_put_64 (abfd, sec->size, &echdr->ch_size);
 		  bfd_put_64 (abfd, 1 << sec->alignment_power,
 			      &echdr->ch_addralign);
+		  /* bfd_log2 (alignof (Elf64_Chdr)) */
+		  bfd_set_section_alignment (abfd, sec, 3);
 		}
 	    }
 	  else
@@ -2354,6 +2358,8 @@ bfd_update_compression_header (bfd *abfd, bfd_byte *contents,
 		 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 (abfd, sec, 0);
 	    }
 	}
     }
@@ -2368,12 +2374,14 @@ bfd_update_compression_header (bfd *abfd, bfd_byte *contents,
    SYNOPSIS
 	bfd_boolean bfd_check_compression_header
 	  (bfd *abfd, bfd_byte *contents, asection *sec,
-	  bfd_size_type *uncompressed_size);
+	  bfd_size_type *uncompressed_size,
+	  unsigned int *uncompressed_alignment_power);
 
 DESCRIPTION
 	Check the compression header at CONTENTS of SEC in ABFD and
-	store the uncompressed size in UNCOMPRESSED_SIZE if the
-	compression header is valid.
+	store the uncompressed size in UNCOMPRESSED_SIZE and the
+	uncompressed data alignment in UNCOMPRESSED_ALIGNMENT_POWER
+	if the compression header is valid.
 
 RETURNS
 	Return TRUE if the compression header is valid.
@@ -2382,7 +2390,8 @@ RETURNS
 bfd_boolean
 bfd_check_compression_header (bfd *abfd, bfd_byte *contents,
 			      asection *sec,
-			      bfd_size_type *uncompressed_size)
+			      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)
@@ -2404,9 +2413,10 @@ bfd_check_compression_header (bfd *abfd, bfd_byte *contents,
 	  chdr.ch_addralign = bfd_get_64 (abfd, &echdr->ch_addralign);
 	}
       if (chdr.ch_type == ELFCOMPRESS_ZLIB
-	  && chdr.ch_addralign == 1U << sec->alignment_power)
+	  && chdr.ch_addralign == (1U << bfd_log2 (chdr.ch_addralign)))
 	{
 	  *uncompressed_size = chdr.ch_size;
+	  *uncompressed_alignment_power = bfd_log2 (chdr.ch_addralign);
 	  return TRUE;
 	}
     }