702 lines
22 KiB
C
702 lines
22 KiB
C
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/* Linux bpf specific support for 64-bit ELF
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Copyright (C) 2019-2022 Free Software Foundation, Inc.
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Contributed by Oracle Inc.
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This file is part of BFD, the Binary File Descriptor library.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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MA 02110-1301, USA. */
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#include "sysdep.h"
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#include "bfd.h"
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#include "libbfd.h"
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#include "elf-bfd.h"
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#include "elf/bpf.h"
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#include "libiberty.h"
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/* In case we're on a 32-bit machine, construct a 64-bit "-1" value. */
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#define MINUS_ONE (~ (bfd_vma) 0)
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#define BASEADDR(SEC) ((SEC)->output_section->vma + (SEC)->output_offset)
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static bfd_reloc_status_type bpf_elf_generic_reloc
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(bfd *, arelent *, asymbol *, void *, asection *, bfd *, char **);
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/* Relocation tables. */
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static reloc_howto_type bpf_elf_howto_table [] =
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{
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/* This reloc does nothing. */
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HOWTO (R_BPF_NONE, /* type */
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0, /* rightshift */
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3, /* size (0 = byte, 1 = short, 2 = long) */
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0, /* bitsize */
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false, /* pc_relative */
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0, /* bitpos */
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complain_overflow_dont, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_NONE", /* name */
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false, /* partial_inplace */
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0, /* src_mask */
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0, /* dst_mask */
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false), /* pcrel_offset */
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/* 64-immediate in LDDW instruction. */
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HOWTO (R_BPF_INSN_64, /* type */
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0, /* rightshift */
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4, /* size (0 = byte, 1 = short, 2 = long) */
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64, /* bitsize */
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false, /* pc_relative */
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32, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_INSN_64", /* name */
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true, /* partial_inplace */
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MINUS_ONE, /* src_mask */
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MINUS_ONE, /* dst_mask */
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true), /* pcrel_offset */
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/* 32-immediate in many instructions. */
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HOWTO (R_BPF_INSN_32, /* type */
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0, /* rightshift */
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2, /* size (0 = byte, 1 = short, 2 = long) */
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32, /* bitsize */
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false, /* pc_relative */
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32, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_INSN_32", /* name */
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true, /* partial_inplace */
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0xffffffff, /* src_mask */
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0xffffffff, /* dst_mask */
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true), /* pcrel_offset */
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/* 16-bit offsets in instructions. */
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HOWTO (R_BPF_INSN_16, /* type */
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0, /* rightshift */
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1, /* size (0 = byte, 1 = short, 2 = long) */
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16, /* bitsize */
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false, /* pc_relative */
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16, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_INSN_16", /* name */
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true, /* partial_inplace */
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0x0000ffff, /* src_mask */
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0x0000ffff, /* dst_mask */
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true), /* pcrel_offset */
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/* 16-bit PC-relative address in jump instructions. */
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HOWTO (R_BPF_INSN_DISP16, /* type */
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0, /* rightshift */
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1, /* size (0 = byte, 1 = short, 2 = long) */
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16, /* bitsize */
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true, /* pc_relative */
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16, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_INSN_DISP16", /* name */
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true, /* partial_inplace */
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0xffff, /* src_mask */
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0xffff, /* dst_mask */
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true), /* pcrel_offset */
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HOWTO (R_BPF_DATA_8_PCREL,
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0, /* rightshift */
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0, /* size (0 = byte, 1 = short, 2 = long) */
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8, /* bitsize */
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true, /* pc_relative */
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0, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_8_PCREL", /* name */
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true, /* partial_inplace */
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0xff, /* src_mask */
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0xff, /* dst_mask */
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true), /* pcrel_offset */
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HOWTO (R_BPF_DATA_16_PCREL,
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0, /* rightshift */
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1, /* size (0 = byte, 1 = short, 2 = long) */
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16, /* bitsize */
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true, /* pc_relative */
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0, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_16_PCREL", /* name */
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false, /* partial_inplace */
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0xffff, /* src_mask */
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0xffff, /* dst_mask */
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true), /* pcrel_offset */
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HOWTO (R_BPF_DATA_32_PCREL,
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0, /* rightshift */
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2, /* size (0 = byte, 1 = short, 2 = long) */
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32, /* bitsize */
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true, /* pc_relative */
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0, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_32_PCREL", /* name */
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false, /* partial_inplace */
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0xffffffff, /* src_mask */
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0xffffffff, /* dst_mask */
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true), /* pcrel_offset */
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HOWTO (R_BPF_DATA_8,
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0, /* rightshift */
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0, /* size (0 = byte, 1 = short, 2 = long) */
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8, /* bitsize */
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false, /* pc_relative */
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0, /* bitpos */
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complain_overflow_unsigned, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_DATA_8", /* name */
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true, /* partial_inplace */
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0xff, /* src_mask */
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0xff, /* dst_mask */
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false), /* pcrel_offset */
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HOWTO (R_BPF_DATA_16,
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0, /* rightshift */
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1, /* size (0 = byte, 1 = short, 2 = long) */
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16, /* bitsize */
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false, /* pc_relative */
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0, /* bitpos */
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complain_overflow_unsigned, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_DATA_16", /* name */
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false, /* partial_inplace */
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0xffff, /* src_mask */
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0xffff, /* dst_mask */
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false), /* pcrel_offset */
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/* 32-bit PC-relative address in call instructions. */
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HOWTO (R_BPF_INSN_DISP32, /* type */
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0, /* rightshift */
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2, /* size (0 = byte, 1 = short, 2 = long) */
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32, /* bitsize */
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true, /* pc_relative */
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32, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_INSN_DISP32", /* name */
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true, /* partial_inplace */
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0xffffffff, /* src_mask */
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0xffffffff, /* dst_mask */
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true), /* pcrel_offset */
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/* 32-bit data. */
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HOWTO (R_BPF_DATA_32, /* type */
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0, /* rightshift */
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2, /* size (0 = byte, 1 = short, 2 = long) */
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32, /* bitsize */
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false, /* pc_relative */
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0, /* bitpos */
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complain_overflow_bitfield, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_DATA_32", /* name */
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false, /* partial_inplace */
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0xffffffff, /* src_mask */
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0xffffffff, /* dst_mask */
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true), /* pcrel_offset */
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/* 64-bit data. */
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HOWTO (R_BPF_DATA_64, /* type */
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0, /* rightshift */
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4, /* size (0 = byte, 1 = short, 2 = long) */
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64, /* bitsize */
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false, /* pc_relative */
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0, /* bitpos */
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complain_overflow_bitfield, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_DATA_64", /* name */
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false, /* partial_inplace */
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0, /* src_mask */
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MINUS_ONE, /* dst_mask */
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true), /* pcrel_offset */
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HOWTO (R_BPF_DATA_64_PCREL,
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0, /* rightshift */
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4, /* size (0 = byte, 1 = short, 2 = long) */
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64, /* bitsize */
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true, /* pc_relative */
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0, /* bitpos */
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complain_overflow_signed, /* complain_on_overflow */
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bpf_elf_generic_reloc, /* special_function */
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"R_BPF_64_PCREL", /* name */
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false, /* partial_inplace */
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MINUS_ONE, /* src_mask */
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MINUS_ONE, /* dst_mask */
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true), /* pcrel_offset */
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};
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#undef AHOW
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/* Map BFD reloc types to bpf ELF reloc types. */
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static reloc_howto_type *
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bpf_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
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bfd_reloc_code_real_type code)
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{
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/* Note that the bpf_elf_howto_table is indexed by the R_ constants.
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Thus, the order that the howto records appear in the table *must*
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match the order of the relocation types defined in
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include/elf/bpf.h. */
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switch (code)
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{
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case BFD_RELOC_NONE:
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return &bpf_elf_howto_table[ (int) R_BPF_NONE];
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case BFD_RELOC_8_PCREL:
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return &bpf_elf_howto_table[ (int) R_BPF_DATA_8_PCREL];
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case BFD_RELOC_16_PCREL:
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return &bpf_elf_howto_table[ (int) R_BPF_DATA_16_PCREL];
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case BFD_RELOC_32_PCREL:
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return &bpf_elf_howto_table[ (int) R_BPF_DATA_32_PCREL];
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case BFD_RELOC_64_PCREL:
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return &bpf_elf_howto_table[ (int) R_BPF_DATA_64_PCREL];
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case BFD_RELOC_8:
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return &bpf_elf_howto_table[ (int) R_BPF_DATA_8];
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case BFD_RELOC_16:
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return &bpf_elf_howto_table[ (int) R_BPF_DATA_16];
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case BFD_RELOC_32:
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return &bpf_elf_howto_table[ (int) R_BPF_DATA_32];
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case BFD_RELOC_64:
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return &bpf_elf_howto_table[ (int) R_BPF_DATA_64];
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case BFD_RELOC_BPF_64:
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return &bpf_elf_howto_table[ (int) R_BPF_INSN_64];
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case BFD_RELOC_BPF_32:
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return &bpf_elf_howto_table[ (int) R_BPF_INSN_32];
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case BFD_RELOC_BPF_16:
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return &bpf_elf_howto_table[ (int) R_BPF_INSN_16];
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case BFD_RELOC_BPF_DISP16:
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return &bpf_elf_howto_table[ (int) R_BPF_INSN_DISP16];
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case BFD_RELOC_BPF_DISP32:
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return &bpf_elf_howto_table[ (int) R_BPF_INSN_DISP32];
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default:
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/* Pacify gcc -Wall. */
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return NULL;
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}
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return NULL;
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}
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/* Map BFD reloc names to bpf ELF reloc names. */
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static reloc_howto_type *
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bpf_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, const char *r_name)
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{
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unsigned int i;
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for (i = 0; i < ARRAY_SIZE (bpf_elf_howto_table); i++)
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if (bpf_elf_howto_table[i].name != NULL
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&& strcasecmp (bpf_elf_howto_table[i].name, r_name) == 0)
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return &bpf_elf_howto_table[i];
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return NULL;
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}
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/* Set the howto pointer for a bpf reloc. */
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static bool
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bpf_info_to_howto (bfd *abfd, arelent *bfd_reloc,
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Elf_Internal_Rela *elf_reloc)
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{
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unsigned int r_type;
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r_type = ELF64_R_TYPE (elf_reloc->r_info);
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if (r_type >= (unsigned int) R_BPF_max)
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{
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/* xgettext:c-format */
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_bfd_error_handler (_("%pB: unsupported relocation type %#x"),
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abfd, r_type);
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bfd_set_error (bfd_error_bad_value);
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return false;
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}
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bfd_reloc->howto = &bpf_elf_howto_table [r_type];
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return true;
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}
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/* Relocate an eBPF ELF section.
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The RELOCATE_SECTION function is called by the new ELF backend linker
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to handle the relocations for a section.
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The relocs are always passed as Rela structures; if the section
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actually uses Rel structures, the r_addend field will always be
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zero.
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This function is responsible for adjusting the section contents as
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necessary, and (if using Rela relocs and generating a relocatable
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output file) adjusting the reloc addend as necessary.
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|
|
This function does not have to worry about setting the reloc
|
||
|
|
address or the reloc symbol index.
|
||
|
|
|
||
|
|
LOCAL_SYMS is a pointer to the swapped in local symbols.
|
||
|
|
|
||
|
|
LOCAL_SECTIONS is an array giving the section in the input file
|
||
|
|
corresponding to the st_shndx field of each local symbol.
|
||
|
|
|
||
|
|
The global hash table entry for the global symbols can be found
|
||
|
|
via elf_sym_hashes (input_bfd).
|
||
|
|
|
||
|
|
When generating relocatable output, this function must handle
|
||
|
|
STB_LOCAL/STT_SECTION symbols specially. The output symbol is
|
||
|
|
going to be the section symbol corresponding to the output
|
||
|
|
section, which means that the addend must be adjusted
|
||
|
|
accordingly. */
|
||
|
|
|
||
|
|
#define sec_addr(sec) ((sec)->output_section->vma + (sec)->output_offset)
|
||
|
|
|
||
|
|
static int
|
||
|
|
bpf_elf_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
|
||
|
|
struct bfd_link_info *info,
|
||
|
|
bfd *input_bfd,
|
||
|
|
asection *input_section,
|
||
|
|
bfd_byte *contents,
|
||
|
|
Elf_Internal_Rela *relocs,
|
||
|
|
Elf_Internal_Sym *local_syms,
|
||
|
|
asection **local_sections)
|
||
|
|
{
|
||
|
|
Elf_Internal_Shdr *symtab_hdr;
|
||
|
|
struct elf_link_hash_entry **sym_hashes;
|
||
|
|
Elf_Internal_Rela *rel;
|
||
|
|
Elf_Internal_Rela *relend;
|
||
|
|
|
||
|
|
symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
|
||
|
|
sym_hashes = elf_sym_hashes (input_bfd);
|
||
|
|
relend = relocs + input_section->reloc_count;
|
||
|
|
|
||
|
|
for (rel = relocs; rel < relend; rel ++)
|
||
|
|
{
|
||
|
|
reloc_howto_type * howto;
|
||
|
|
unsigned long r_symndx;
|
||
|
|
Elf_Internal_Sym * sym;
|
||
|
|
asection * sec;
|
||
|
|
struct elf_link_hash_entry * h;
|
||
|
|
bfd_vma relocation;
|
||
|
|
bfd_reloc_status_type r;
|
||
|
|
const char * name = NULL;
|
||
|
|
int r_type ATTRIBUTE_UNUSED;
|
||
|
|
bfd_signed_vma addend;
|
||
|
|
bfd_byte * where;
|
||
|
|
|
||
|
|
r_type = ELF64_R_TYPE (rel->r_info);
|
||
|
|
r_symndx = ELF64_R_SYM (rel->r_info);
|
||
|
|
howto = bpf_elf_howto_table + ELF64_R_TYPE (rel->r_info);
|
||
|
|
h = NULL;
|
||
|
|
sym = NULL;
|
||
|
|
sec = NULL;
|
||
|
|
where = contents + rel->r_offset;
|
||
|
|
|
||
|
|
if (r_symndx < symtab_hdr->sh_info)
|
||
|
|
{
|
||
|
|
sym = local_syms + r_symndx;
|
||
|
|
sec = local_sections [r_symndx];
|
||
|
|
relocation = BASEADDR (sec) + sym->st_value;
|
||
|
|
|
||
|
|
name = bfd_elf_string_from_elf_section
|
||
|
|
(input_bfd, symtab_hdr->sh_link, sym->st_name);
|
||
|
|
name = name == NULL ? bfd_section_name (sec) : name;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
bool warned ATTRIBUTE_UNUSED;
|
||
|
|
bool unresolved_reloc ATTRIBUTE_UNUSED;
|
||
|
|
bool ignored ATTRIBUTE_UNUSED;
|
||
|
|
|
||
|
|
RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
|
||
|
|
r_symndx, symtab_hdr, sym_hashes,
|
||
|
|
h, sec, relocation,
|
||
|
|
unresolved_reloc, warned, ignored);
|
||
|
|
|
||
|
|
name = h->root.root.string;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (sec != NULL && discarded_section (sec))
|
||
|
|
RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
|
||
|
|
rel, 1, relend, howto, 0, contents);
|
||
|
|
|
||
|
|
if (bfd_link_relocatable (info))
|
||
|
|
continue;
|
||
|
|
|
||
|
|
switch (howto->type)
|
||
|
|
{
|
||
|
|
case R_BPF_INSN_DISP16:
|
||
|
|
case R_BPF_INSN_DISP32:
|
||
|
|
{
|
||
|
|
/* Make the relocation PC-relative, and change its unit to
|
||
|
|
64-bit words. Note we need *signed* arithmetic
|
||
|
|
here. */
|
||
|
|
relocation = ((bfd_signed_vma) relocation
|
||
|
|
- (sec_addr (input_section) + rel->r_offset));
|
||
|
|
relocation = (bfd_signed_vma) relocation / 8;
|
||
|
|
|
||
|
|
/* Get the addend from the instruction and apply it. */
|
||
|
|
addend = bfd_get (howto->bitsize, input_bfd,
|
||
|
|
contents + rel->r_offset
|
||
|
|
+ (howto->bitsize == 16 ? 2 : 4));
|
||
|
|
|
||
|
|
if ((addend & (((~howto->src_mask) >> 1) & howto->src_mask)) != 0)
|
||
|
|
addend -= (((~howto->src_mask) >> 1) & howto->src_mask) << 1;
|
||
|
|
relocation += addend;
|
||
|
|
|
||
|
|
/* Write out the relocated value. */
|
||
|
|
bfd_put (howto->bitsize, input_bfd, relocation,
|
||
|
|
contents + rel->r_offset
|
||
|
|
+ (howto->bitsize == 16 ? 2 : 4));
|
||
|
|
|
||
|
|
r = bfd_reloc_ok;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case R_BPF_DATA_8:
|
||
|
|
case R_BPF_DATA_16:
|
||
|
|
case R_BPF_DATA_32:
|
||
|
|
case R_BPF_DATA_64:
|
||
|
|
{
|
||
|
|
addend = bfd_get (howto->bitsize, input_bfd, where);
|
||
|
|
relocation += addend;
|
||
|
|
bfd_put (howto->bitsize, input_bfd, relocation, where);
|
||
|
|
|
||
|
|
r = bfd_reloc_ok;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case R_BPF_INSN_16:
|
||
|
|
{
|
||
|
|
|
||
|
|
addend = bfd_get_16 (input_bfd, where + 2);
|
||
|
|
relocation += addend;
|
||
|
|
bfd_put_16 (input_bfd, relocation, where + 2);
|
||
|
|
|
||
|
|
r = bfd_reloc_ok;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case R_BPF_INSN_32:
|
||
|
|
{
|
||
|
|
/* Write relocated value */
|
||
|
|
|
||
|
|
addend = bfd_get_32 (input_bfd, where + 4);
|
||
|
|
relocation += addend;
|
||
|
|
bfd_put_32 (input_bfd, relocation, where + 4);
|
||
|
|
|
||
|
|
r = bfd_reloc_ok;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case R_BPF_INSN_64:
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
LDDW instructions are 128 bits long, with a 64-bit immediate.
|
||
|
|
The lower 32 bits of the immediate are in the same position
|
||
|
|
as the imm32 field of other instructions.
|
||
|
|
The upper 32 bits of the immediate are stored at the end of
|
||
|
|
the instruction.
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
/* Get the addend. The upper and lower 32 bits are split.
|
||
|
|
'where' is the beginning of the 16-byte instruction. */
|
||
|
|
addend = bfd_get_32 (input_bfd, where + 4);
|
||
|
|
addend |= (bfd_get_32 (input_bfd, where + 12) << 32);
|
||
|
|
|
||
|
|
relocation += addend;
|
||
|
|
|
||
|
|
bfd_put_32 (input_bfd, (relocation & 0xFFFFFFFF), where + 4);
|
||
|
|
bfd_put_32 (input_bfd, (relocation >> 32), where + 12);
|
||
|
|
r = bfd_reloc_ok;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
default:
|
||
|
|
r = bfd_reloc_notsupported;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (r == bfd_reloc_ok)
|
||
|
|
r = bfd_check_overflow (howto->complain_on_overflow,
|
||
|
|
howto->bitsize,
|
||
|
|
howto->rightshift,
|
||
|
|
64, relocation);
|
||
|
|
|
||
|
|
if (r != bfd_reloc_ok)
|
||
|
|
{
|
||
|
|
const char * msg = NULL;
|
||
|
|
|
||
|
|
switch (r)
|
||
|
|
{
|
||
|
|
case bfd_reloc_overflow:
|
||
|
|
(*info->callbacks->reloc_overflow)
|
||
|
|
(info, (h ? &h->root : NULL), name, howto->name,
|
||
|
|
(bfd_vma) 0, input_bfd, input_section, rel->r_offset);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case bfd_reloc_undefined:
|
||
|
|
(*info->callbacks->undefined_symbol)
|
||
|
|
(info, name, input_bfd, input_section, rel->r_offset, true);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case bfd_reloc_outofrange:
|
||
|
|
msg = _("internal error: out of range error");
|
||
|
|
break;
|
||
|
|
|
||
|
|
case bfd_reloc_notsupported:
|
||
|
|
if (sym != NULL) /* Only if it's not an unresolved symbol. */
|
||
|
|
msg = _("internal error: relocation not supported");
|
||
|
|
break;
|
||
|
|
|
||
|
|
case bfd_reloc_dangerous:
|
||
|
|
msg = _("internal error: dangerous relocation");
|
||
|
|
break;
|
||
|
|
|
||
|
|
default:
|
||
|
|
msg = _("internal error: unknown error");
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (msg)
|
||
|
|
(*info->callbacks->warning) (info, msg, name, input_bfd,
|
||
|
|
input_section, rel->r_offset);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Merge backend specific data from an object file to the output
|
||
|
|
object file when linking. */
|
||
|
|
|
||
|
|
static bool
|
||
|
|
elf64_bpf_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info)
|
||
|
|
{
|
||
|
|
/* Check if we have the same endianness. */
|
||
|
|
if (! _bfd_generic_verify_endian_match (ibfd, info))
|
||
|
|
return false;
|
||
|
|
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* A generic howto special function for installing BPF relocations.
|
||
|
|
This function will be called by the assembler (via bfd_install_relocation),
|
||
|
|
and by various get_relocated_section_contents functions.
|
||
|
|
At link time, bpf_elf_relocate_section will resolve the final relocations.
|
||
|
|
|
||
|
|
BPF instructions are always big endian, and this approach avoids problems in
|
||
|
|
bfd_install_relocation. */
|
||
|
|
|
||
|
|
static bfd_reloc_status_type
|
||
|
|
bpf_elf_generic_reloc (bfd *abfd, arelent *reloc_entry, asymbol *symbol,
|
||
|
|
void *data, asection *input_section,
|
||
|
|
bfd *output_bfd ATTRIBUTE_UNUSED,
|
||
|
|
char **error_message ATTRIBUTE_UNUSED)
|
||
|
|
{
|
||
|
|
|
||
|
|
bfd_signed_vma relocation;
|
||
|
|
bfd_reloc_status_type status;
|
||
|
|
bfd_byte *where;
|
||
|
|
|
||
|
|
/* Sanity check that the address is in range. */
|
||
|
|
bfd_size_type end = bfd_get_section_limit_octets (abfd, input_section);
|
||
|
|
bfd_size_type reloc_size;
|
||
|
|
if (reloc_entry->howto->type == R_BPF_INSN_64)
|
||
|
|
reloc_size = 16;
|
||
|
|
else
|
||
|
|
reloc_size = (reloc_entry->howto->bitsize
|
||
|
|
+ reloc_entry->howto->bitpos) / 8;
|
||
|
|
|
||
|
|
if (reloc_entry->address > end
|
||
|
|
|| end - reloc_entry->address < reloc_size)
|
||
|
|
return bfd_reloc_outofrange;
|
||
|
|
|
||
|
|
/* Get the symbol value. */
|
||
|
|
if (bfd_is_com_section (symbol->section))
|
||
|
|
relocation = 0;
|
||
|
|
else
|
||
|
|
relocation = symbol->value;
|
||
|
|
|
||
|
|
if (symbol->flags & BSF_SECTION_SYM)
|
||
|
|
/* Relocation against a section symbol: add in the section base address. */
|
||
|
|
relocation += BASEADDR (symbol->section);
|
||
|
|
|
||
|
|
relocation += reloc_entry->addend;
|
||
|
|
|
||
|
|
where = (bfd_byte *) data + reloc_entry->address;
|
||
|
|
|
||
|
|
status = bfd_check_overflow (reloc_entry->howto->complain_on_overflow,
|
||
|
|
reloc_entry->howto->bitsize,
|
||
|
|
reloc_entry->howto->rightshift, 64, relocation);
|
||
|
|
|
||
|
|
if (status != bfd_reloc_ok)
|
||
|
|
return status;
|
||
|
|
|
||
|
|
/* Now finally install the relocation. */
|
||
|
|
if (reloc_entry->howto->type == R_BPF_INSN_64)
|
||
|
|
{
|
||
|
|
/* lddw is a 128-bit (!) instruction that allows loading a 64-bit
|
||
|
|
immediate into a register. the immediate is split in half, with the
|
||
|
|
lower 32 bits in the same position as the imm32 field of other
|
||
|
|
instructions, and the upper 32 bits placed at the very end of the
|
||
|
|
instruction. that is, there are 32 unused bits between them. */
|
||
|
|
|
||
|
|
bfd_put_32 (abfd, (relocation & 0xFFFFFFFF), where + 4);
|
||
|
|
bfd_put_32 (abfd, (relocation >> 32), where + 12);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
/* For other kinds of relocations, the relocated value simply goes
|
||
|
|
BITPOS bits from the start of the entry. This is always a multiple
|
||
|
|
of 8, i.e. whole bytes. */
|
||
|
|
bfd_put (reloc_entry->howto->bitsize, abfd, relocation,
|
||
|
|
where + reloc_entry->howto->bitpos / 8);
|
||
|
|
}
|
||
|
|
|
||
|
|
reloc_entry->addend = relocation;
|
||
|
|
reloc_entry->address += input_section->output_offset;
|
||
|
|
|
||
|
|
return bfd_reloc_ok;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/* The macros below configure the architecture. */
|
||
|
|
|
||
|
|
#define TARGET_LITTLE_SYM bpf_elf64_le_vec
|
||
|
|
#define TARGET_LITTLE_NAME "elf64-bpfle"
|
||
|
|
|
||
|
|
#define TARGET_BIG_SYM bpf_elf64_be_vec
|
||
|
|
#define TARGET_BIG_NAME "elf64-bpfbe"
|
||
|
|
|
||
|
|
#define ELF_ARCH bfd_arch_bpf
|
||
|
|
#define ELF_MACHINE_CODE EM_BPF
|
||
|
|
|
||
|
|
#define ELF_MAXPAGESIZE 0x100000
|
||
|
|
|
||
|
|
#define elf_info_to_howto_rel bpf_info_to_howto
|
||
|
|
#define elf_info_to_howto bpf_info_to_howto
|
||
|
|
|
||
|
|
#define elf_backend_may_use_rel_p 1
|
||
|
|
#define elf_backend_may_use_rela_p 0
|
||
|
|
#define elf_backend_default_use_rela_p 0
|
||
|
|
#define elf_backend_relocate_section bpf_elf_relocate_section
|
||
|
|
|
||
|
|
#define elf_backend_can_gc_sections 0
|
||
|
|
|
||
|
|
#define elf_symbol_leading_char '_'
|
||
|
|
#define bfd_elf64_bfd_reloc_type_lookup bpf_reloc_type_lookup
|
||
|
|
#define bfd_elf64_bfd_reloc_name_lookup bpf_reloc_name_lookup
|
||
|
|
|
||
|
|
#define bfd_elf64_bfd_merge_private_bfd_data elf64_bpf_merge_private_bfd_data
|
||
|
|
|
||
|
|
#include "elf64-target.h"
|