mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-11-23 01:53:38 +08:00
bfd/ELF: restrict file alignment for object files
While for executables properly aligning sections within the file can be quite relevant, the same is of pretty little importance for relocatable object files. Avoid passing "true" into _bfd_elf_assign_file_position_for_section() when dealing with object files, but compensate minimally by applying log_file_align in such cases as a cap to the alignment put in place.
This commit is contained in:
Jan Beulich
parent
873e7b6cf6
commit
1f1b5e506b
@ -2540,7 +2540,7 @@ extern long _bfd_elf_link_lookup_local_dynindx
|
||||
extern bool _bfd_elf_compute_section_file_positions
|
||||
(bfd *, struct bfd_link_info *);
|
||||
extern file_ptr _bfd_elf_assign_file_position_for_section
|
||||
(Elf_Internal_Shdr *, file_ptr, bool);
|
||||
(Elf_Internal_Shdr *, file_ptr, bool, unsigned char);
|
||||
extern bool _bfd_elf_modify_headers
|
||||
(bfd *, struct bfd_link_info *);
|
||||
|
||||
|
||||
44
bfd/elf.c
44
bfd/elf.c
@ -4572,10 +4572,23 @@ align_file_position (file_ptr off, int align)
|
||||
file_ptr
|
||||
_bfd_elf_assign_file_position_for_section (Elf_Internal_Shdr *i_shdrp,
|
||||
file_ptr offset,
|
||||
bool align)
|
||||
bool align,
|
||||
unsigned char log_file_align)
|
||||
{
|
||||
if (align && i_shdrp->sh_addralign > 1)
|
||||
offset = BFD_ALIGN (offset, i_shdrp->sh_addralign & -i_shdrp->sh_addralign);
|
||||
if (i_shdrp->sh_addralign > 1)
|
||||
{
|
||||
file_ptr salign = i_shdrp->sh_addralign & -i_shdrp->sh_addralign;
|
||||
|
||||
if (align)
|
||||
offset = BFD_ALIGN (offset, salign);
|
||||
else if (log_file_align)
|
||||
{
|
||||
/* Heuristic: Cap alignment at log_file_align. */
|
||||
file_ptr falign = 1u << log_file_align;
|
||||
|
||||
offset = BFD_ALIGN (offset, salign < falign ? salign : falign);
|
||||
}
|
||||
}
|
||||
i_shdrp->sh_offset = offset;
|
||||
if (i_shdrp->bfd_section != NULL)
|
||||
i_shdrp->bfd_section->filepos = offset;
|
||||
@ -4663,18 +4676,18 @@ _bfd_elf_compute_section_file_positions (bfd *abfd,
|
||||
off = elf_next_file_pos (abfd);
|
||||
|
||||
hdr = & elf_symtab_hdr (abfd);
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true);
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true, 0);
|
||||
|
||||
if (elf_symtab_shndx_list (abfd) != NULL)
|
||||
{
|
||||
hdr = & elf_symtab_shndx_list (abfd)->hdr;
|
||||
if (hdr->sh_size != 0)
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true);
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true, 0);
|
||||
/* FIXME: What about other symtab_shndx sections in the list ? */
|
||||
}
|
||||
|
||||
hdr = &elf_tdata (abfd)->strtab_hdr;
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true);
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true, 0);
|
||||
|
||||
elf_next_file_pos (abfd) = off;
|
||||
|
||||
@ -6548,8 +6561,8 @@ assign_file_positions_for_non_load_sections (bfd *abfd,
|
||||
else
|
||||
align = hdr->sh_addralign & -hdr->sh_addralign;
|
||||
off += vma_page_aligned_bias (hdr->sh_addr, off, align);
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off,
|
||||
false);
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, false,
|
||||
bed->s->log_file_align);
|
||||
}
|
||||
else if (((hdr->sh_type == SHT_REL || hdr->sh_type == SHT_RELA)
|
||||
&& hdr->bfd_section == NULL)
|
||||
@ -6566,7 +6579,7 @@ assign_file_positions_for_non_load_sections (bfd *abfd,
|
||||
|| hdr == i_shdrpp[elf_shstrtab_sec (abfd)])
|
||||
hdr->sh_offset = -1;
|
||||
else
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true);
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true, 0);
|
||||
}
|
||||
elf_next_file_pos (abfd) = off;
|
||||
|
||||
@ -6803,7 +6816,8 @@ assign_file_positions_except_relocs (bfd *abfd,
|
||||
hdr->sh_offset = -1;
|
||||
}
|
||||
else
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, true);
|
||||
off = _bfd_elf_assign_file_position_for_section (hdr, off, false,
|
||||
0);
|
||||
}
|
||||
|
||||
elf_next_file_pos (abfd) = off;
|
||||
@ -7018,7 +7032,7 @@ _bfd_elf_assign_file_positions_for_non_load (bfd *abfd)
|
||||
Elf_Internal_Shdr **shdrpp, **end_shdrpp;
|
||||
Elf_Internal_Shdr *shdrp;
|
||||
Elf_Internal_Ehdr *i_ehdrp;
|
||||
const struct elf_backend_data *bed;
|
||||
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
|
||||
|
||||
/* Skip non-load sections without section header. */
|
||||
if ((abfd->flags & BFD_NO_SECTION_HEADER) != 0)
|
||||
@ -7086,7 +7100,10 @@ _bfd_elf_assign_file_positions_for_non_load (bfd *abfd)
|
||||
sec->contents = NULL;
|
||||
}
|
||||
|
||||
off = _bfd_elf_assign_file_position_for_section (shdrp, off, true);
|
||||
off = _bfd_elf_assign_file_position_for_section (shdrp, off,
|
||||
(abfd->flags & (EXEC_P | DYNAMIC))
|
||||
|| bfd_get_format (abfd) == bfd_core,
|
||||
bed->s->log_file_align);
|
||||
}
|
||||
}
|
||||
|
||||
@ -7095,11 +7112,10 @@ _bfd_elf_assign_file_positions_for_non_load (bfd *abfd)
|
||||
_bfd_elf_strtab_finalize (elf_shstrtab (abfd));
|
||||
shdrp = &elf_tdata (abfd)->shstrtab_hdr;
|
||||
shdrp->sh_size = _bfd_elf_strtab_size (elf_shstrtab (abfd));
|
||||
off = _bfd_elf_assign_file_position_for_section (shdrp, off, true);
|
||||
off = _bfd_elf_assign_file_position_for_section (shdrp, off, true, 0);
|
||||
|
||||
/* Place the section headers. */
|
||||
i_ehdrp = elf_elfheader (abfd);
|
||||
bed = get_elf_backend_data (abfd);
|
||||
off = align_file_position (off, 1 << bed->s->log_file_align);
|
||||
i_ehdrp->e_shoff = off;
|
||||
off += i_ehdrp->e_shnum * i_ehdrp->e_shentsize;
|
||||
|
||||
@ -12926,7 +12926,7 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
|
||||
{
|
||||
file_ptr off = elf_next_file_pos (abfd);
|
||||
|
||||
_bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
|
||||
_bfd_elf_assign_file_position_for_section (symtab_hdr, off, true, 0);
|
||||
|
||||
/* Note that at this point elf_next_file_pos (abfd) is
|
||||
incorrect. We do not yet know the size of the .symtab section.
|
||||
@ -13370,7 +13370,7 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
|
||||
symtab_shndx_hdr->sh_size = amt;
|
||||
|
||||
off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
|
||||
off, true);
|
||||
off, true, 0);
|
||||
|
||||
if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
|
||||
|| (bfd_write (flinfo.symshndxbuf, amt, abfd) != amt))
|
||||
@ -13394,7 +13394,7 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
|
||||
symstrtab_hdr->sh_addralign = 1;
|
||||
|
||||
off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr,
|
||||
off, true);
|
||||
off, true, 0);
|
||||
elf_next_file_pos (abfd) = off;
|
||||
|
||||
if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
|
||||
|
||||
@ -10,9 +10,9 @@ There are 5 section headers, starting at offset 0x[0-9a-f]+:
|
||||
Section Headers:
|
||||
\[Nr\] Name Type Addr Off Size ES Flg Lk Inf Al
|
||||
\[ 0\] NULL 00000000 000000 000000 00 0 0 0
|
||||
\[ 1\] .text PROGBITS 00000000 000040 00001b 00 AX 0 0 16
|
||||
\[ 2\] .data PROGBITS 00000000 00005b 000000 00 WA 0 0 1
|
||||
\[ 3\] .bss NOBITS 00000000 00005b 000000 00 WA 0 0 1
|
||||
\[ 4\] .shstrtab STRTAB 00000000 [0-9a-f]+ 00001c 00 . 0 0 1
|
||||
\[ 1\] .text PROGBITS 00000000 0000.. 00001b 00 AX 0 0 16
|
||||
\[ 2\] .data PROGBITS 00000000 0000.. 000000 00 WA 0 0 1
|
||||
\[ 3\] .bss NOBITS 00000000 0000.. 000000 00 WA 0 0 1
|
||||
\[ 4\] .shstrtab STRTAB 00000000 0000.. 00001c 00 .. 0 0 1
|
||||
Key to Flags:
|
||||
#...
|
||||
|
||||
@ -10,9 +10,9 @@ There are 5 section headers, starting at offset 0x[0-9a-f]+:
|
||||
Section Headers:
|
||||
\[Nr\] Name Type Addr Off Size ES Flg Lk Inf Al
|
||||
\[ 0\] NULL 00000000 000000 000000 00 0 0 0
|
||||
\[ 1\] .text PROGBITS 00000000 000040 00001b 00 AX 0 0 16
|
||||
\[ 2\] .data PROGBITS 00000000 00005b 000000 00 WA 0 0 1
|
||||
\[ 3\] .bss NOBITS 00000000 00005b 000000 00 WA 0 0 1
|
||||
\[ 4\] .shstrtab STRTAB 00000000 [0-9a-f]+ 00001c 00 .* 0 0 1
|
||||
\[ 1\] .text PROGBITS 00000000 0000.. 00001b 00 AX 0 0 16
|
||||
\[ 2\] .data PROGBITS 00000000 0000.. 000000 00 WA 0 0 1
|
||||
\[ 3\] .bss NOBITS 00000000 0000.. 000000 00 WA 0 0 1
|
||||
\[ 4\] .shstrtab STRTAB 00000000 0000.. 00001c 00 .. 0 0 1
|
||||
Key to Flags:
|
||||
#...
|
||||
|
||||
@ -10,7 +10,7 @@ Section Headers:
|
||||
# MIPS targets put .rela.text here.
|
||||
#...
|
||||
+\[ .\] .* +PROGBITS +00000000 0000(3c|40|44|48|50) 0000(04|10) 00 +WA +0 +0 +(.|..)
|
||||
+\[ .\] .* +NOBITS +00000000 0000(40|44|48|4c|60) 000000 00 +WA +0 +0 +(.|..)
|
||||
+\[ .\] .* +NOBITS +00000000 0+[0-9a-f]+ 000000 00 +WA +0 +0 +(.|..)
|
||||
# ARM targets put .ARM.attributes here.
|
||||
# MIPS targets put .reginfo, .mdebug, .MIPS.abiflags and .gnu.attributes here.
|
||||
# v850 targets put .call_table_data and .call_table_text here.
|
||||
|
||||
@ -11,10 +11,10 @@ Section Headers:
|
||||
Size EntSize Flags Link Info Align
|
||||
\[ 0\] NULL 0000000000000000 00000000
|
||||
0000000000000000 0000000000000000 0 0 0
|
||||
\[ 1\] \.text PROGBITS 0000000000000000 00000040
|
||||
\[ 1\] \.text PROGBITS 0000000000000000 000000..
|
||||
0000000000000000 0000000000000000 AX 0 0 1
|
||||
\[ 2\] \.data PROGBITS 0000000000000000 00000040
|
||||
\[ 2\] \.data PROGBITS 0000000000000000 000000..
|
||||
0000000000000008 0000000000000000 WA 0 0 64
|
||||
\[ 3\] \.bss NOBITS 0000000000000000 00000080
|
||||
\[ 3\] \.bss NOBITS 0000000000000000 000000..
|
||||
000000000000000c 0000000000000000 WA 0 0 64
|
||||
#...
|
||||
|
||||
@ -4,7 +4,7 @@
|
||||
#readelf: -u
|
||||
#target: [is_elf_format]
|
||||
|
||||
Unwind section '.ARM.exidx' at offset 0x5c contains 1 entry:
|
||||
Unwind section '.ARM.exidx' at offset 0x[0-9a-f]+ contains 1 entry:
|
||||
|
||||
0x0: @0x0
|
||||
Compact model index: 1
|
||||
|
||||
@ -8,15 +8,15 @@ Section Headers:
|
||||
Size EntSize Flags Link Info Align
|
||||
\[ 0\] NULL 0000000000000000 00000000
|
||||
0000000000000000 0000000000000000 0 0 0
|
||||
\[ 1\] \.group GROUP 0000000000000000 00000040
|
||||
\[ 1\] \.group GROUP 0000000000000000 [0-9a-f]+
|
||||
0000000000000008 0000000000000004 6 6 4
|
||||
\[ 2\] \.text PROGBITS 0000000000000000 00000050
|
||||
\[ 2\] \.text PROGBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000000 0000000000000000 AX 0 0 16
|
||||
\[ 3\] \.data PROGBITS 0000000000000000 00000050
|
||||
\[ 3\] \.data PROGBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000000 0000000000000000 WA 0 0 1
|
||||
\[ 4\] \.bss NOBITS 0000000000000000 00000050
|
||||
\[ 4\] \.bss NOBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000000 0000000000000000 WA 0 0 1
|
||||
\[ 5\] \.text PROGBITS 0000000000000000 00000050
|
||||
\[ 5\] \.text PROGBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000010 0000000000000000 AXG 0 0 16
|
||||
\[ 6\] \.symtab SYMTAB 0000000000000000 .*
|
||||
00000000000000c0 0000000000000018 7 8 8
|
||||
|
||||
@ -9,19 +9,19 @@ Section Headers:
|
||||
Size EntSize Flags Link Info Align
|
||||
\[ 0\] NULL 0000000000000000 00000000
|
||||
0000000000000000 0000000000000000 0 0 0
|
||||
\[ 1\] \.group GROUP 0000000000000000 00000040
|
||||
\[ 1\] \.group GROUP 0000000000000000 [0-9a-f]+
|
||||
0000000000000014 0000000000000004 9 5 4
|
||||
\[ 2\] \.text PROGBITS 0000000000000000 00000060
|
||||
\[ 2\] \.text PROGBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000000 0000000000000000 AX 0 0 16
|
||||
\[ 3\] \.data PROGBITS 0000000000000000 00000060
|
||||
\[ 3\] \.data PROGBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000000 0000000000000000 WA 0 0 1
|
||||
\[ 4\] \.bss NOBITS 0000000000000000 00000060
|
||||
\[ 4\] \.bss NOBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000000 0000000000000000 WA 0 0 1
|
||||
\[ 5\] \.gnu\.linkonce\.t\.f PROGBITS 0000000000000000 00000060
|
||||
\[ 5\] \.gnu\.linkonce\.t\.f PROGBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000000 0000000000000000 AXG 0 0 16
|
||||
\[ 6\] \.gnu\.linkonce\.ia6 PROGBITS 0000000000000000 00000060
|
||||
\[ 6\] \.gnu\.linkonce\.ia6 PROGBITS 0000000000000000 [0-9a-f]+
|
||||
0000000000000010 0000000000000000 AG 0 0 8
|
||||
\[ 7\] \.gnu\.linkonce\.ia6 IA_64_UNWIND 0000000000000000 00000070
|
||||
\[ 7\] \.gnu\.linkonce\.ia6 IA_64_UNWIND 0000000000000000 [0-9a-f]+
|
||||
0000000000000018 0000000000000000 ALG 5 5 8
|
||||
\[ 8\] \.rela\.gnu\.linkonc RELA 0000000000000000 .*
|
||||
0000000000000048 0000000000000018 IG 9 7 8
|
||||
|
||||
@ -1,11 +1,11 @@
|
||||
#readelf: -Sr -T -x1 -x4
|
||||
There are 11 section headers, starting at offset .*:
|
||||
#...
|
||||
\[ 4\] \.MMIX\.spec_data\.2 PROGBITS 0+ 0+48
|
||||
\[ 4\] \.MMIX\.spec_data\.2 PROGBITS 0+ [0-9a-f]+
|
||||
0+10 0+ 0 0 8
|
||||
\[ 5\] \.rela\.MMIX\.spec_d RELA 0+ .*
|
||||
+0+30 0+18 +I +8 +4 +8
|
||||
\[ 6\] \.MMIX\.spec_data\.3 PROGBITS 0+ 0+58
|
||||
\[ 6\] \.MMIX\.spec_data\.3 PROGBITS 0+ [0-9a-f]+
|
||||
0+8 0+ 0 0 8
|
||||
\[ 7\] \.rela\.MMIX\.spec_d RELA 0+ .*
|
||||
+0+18 +0+18 +I +8 +6 +8
|
||||
|
||||
@ -1,11 +1,11 @@
|
||||
#...
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_info PROGBITS +0+ 0+28a 0+42 00 +E 0 +0 1
|
||||
\[[ 0-9]+\] .rela.gnu.debuglto_.debug_info RELA +0+ 0+810 0+f0 18 +I 26 17 8
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_abbrev PROGBITS +0+ 0+2cc 0+26 00 +E 0 +0 1
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_macro PROGBITS +0+ 0+2f2 0+2a 00 +E 0 +0 1
|
||||
\[[ 0-9]+\] .rela.gnu.debuglto_.debug_macro RELA +0+ 0+900 0+60 18 +I 26 20 8
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_macro PROGBITS +0+ 0+31c 0+10 00 GE 0 +0 1
|
||||
\[[ 0-9]+\] .rela.gnu.debuglto_.debug_macro RELA +0+ 0+960 0+30 18 IG 26 22 8
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_line PROGBITS +0+ 0+32c 0+8a 00 +E 0 +0 1
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_str PROGBITS +0+ 0+3b6 0+15c 01 MSE 0 +0 1
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_info PROGBITS +0+ [0-9a-f]+ 0+42 00 +E 0 +0 1
|
||||
\[[ 0-9]+\] .rela.gnu.debuglto_.debug_info RELA +0+ [0-9a-f]+ 0+f0 18 +I 26 17 8
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_abbrev PROGBITS +0+ [0-9a-f]+ 0+26 00 +E 0 +0 1
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_macro PROGBITS +0+ [0-9a-f]+ 0+2a 00 +E 0 +0 1
|
||||
\[[ 0-9]+\] .rela.gnu.debuglto_.debug_macro RELA +0+ [0-9a-f]+ 0+60 18 +I 26 20 8
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_macro PROGBITS +0+ [0-9a-f]+ 0+10 00 GE 0 +0 1
|
||||
\[[ 0-9]+\] .rela.gnu.debuglto_.debug_macro RELA +0+ [0-9a-f]+ 0+30 18 IG 26 22 8
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_line PROGBITS +0+ [0-9a-f]+ 0+8a 00 +E 0 +0 1
|
||||
\[[ 0-9]+\] .gnu.debuglto_.debug_str PROGBITS +0+ [0-9a-f]+ 0+15c 01 MSE 0 +0 1
|
||||
#pass
|
||||
|
||||
Loading…
Reference in New Issue
Block a user