From 4c398cc06d333fcb04772c04ea18db68587e8a1f Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Mon, 3 May 2021 13:25:12 +0200 Subject: [PATCH] x86: don't request useless overflow checking Relocations with a bitsize matching the architecture's address width can't usefully use an overflow checking approach other than "dont" or "signed": All others involve perhaps complex calculations in _bfd_relocate_contents() (or, not as severe, in bfd_check_overflow()) without ever finding anything to complain about - because of the address width masking applied. Avoid this unnecessary overhead and switch all such reloc types to "dont". Note that "signed" checking with rela relocations (i.e. x86-64 here) is only going to be useful if the addend actually got passed to _bfd_relocate_contents() (and maybe others) instead of bogusly adding in prior section contents (which apparently is assumed to be zero, and hence again no overflow would ever be detected). See https://sourceware.org/pipermail/binutils/2021-April/116164.html. --- bfd/ChangeLog | 7 ++++++ bfd/elf32-i386.c | 54 +++++++++++++++++++++++----------------------- bfd/elf64-x86-64.c | 26 +++++++++++----------- 3 files changed, 47 insertions(+), 40 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index cdcf5d76167..2659710787a 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,10 @@ +2021-05-03 Jan Beulich + + * elf32-i386.c (elf_howto_table): Switch all 32-bit relocs to + complain_overflow_dont. + * elf64-x86-64.c (x86_64_elf_howto_table): Switch all 64-bit + relocs to complain_overflow_dont. + 2021-05-03 Alan Modra * elf32-ppc.c (allocate_dynrelocs): Keep dyn_relocs for undefweak diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c index ffe764422ff..4451f9b451c 100644 --- a/bfd/elf32-i386.c +++ b/bfd/elf32-i386.c @@ -33,34 +33,34 @@ static reloc_howto_type elf_howto_table[]= HOWTO(R_386_NONE, 0, 3, 0, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_NONE", true, 0x00000000, 0x00000000, false), - HOWTO(R_386_32, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_PC32, 0, 2, 32, true, 0, complain_overflow_bitfield, + HOWTO(R_386_PC32, 0, 2, 32, true, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_PC32", true, 0xffffffff, 0xffffffff, true), - HOWTO(R_386_GOT32, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_GOT32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_GOT32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_PLT32, 0, 2, 32, true, 0, complain_overflow_bitfield, + HOWTO(R_386_PLT32, 0, 2, 32, true, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_PLT32", true, 0xffffffff, 0xffffffff, true), - HOWTO(R_386_COPY, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_COPY, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_COPY", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_GLOB_DAT, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_GLOB_DAT, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_GLOB_DAT", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_JUMP_SLOT, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_JUMP_SLOT, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_JUMP_SLOT", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_RELATIVE, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_RELATIVE, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_RELATIVE", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_GOTOFF, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_GOTOFF, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_GOTOFF", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_GOTPC, 0, 2, 32, true, 0, complain_overflow_bitfield, + HOWTO(R_386_GOTPC, 0, 2, 32, true, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_GOTPC", true, 0xffffffff, 0xffffffff, true), @@ -72,22 +72,22 @@ static reloc_howto_type elf_howto_table[]= #define R_386_ext_offset (R_386_TLS_TPOFF - R_386_standard) /* These relocs are a GNU extension. */ - HOWTO(R_386_TLS_TPOFF, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_TPOFF, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_TPOFF", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_IE, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_IE, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_IE", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_GOTIE, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_GOTIE, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_GOTIE", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_LE, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_LE, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_LE", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_GD, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_GD, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_GD", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_LDM, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_LDM, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_LDM", true, 0xffffffff, 0xffffffff, false), HOWTO(R_386_16, 0, 1, 16, false, 0, complain_overflow_bitfield, @@ -106,40 +106,40 @@ static reloc_howto_type elf_howto_table[]= #define R_386_ext (R_386_PC8 + 1 - R_386_ext_offset) #define R_386_tls_offset (R_386_TLS_LDO_32 - R_386_ext) /* These are common with Solaris TLS implementation. */ - HOWTO(R_386_TLS_LDO_32, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_LDO_32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_LDO_32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_IE_32, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_IE_32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_IE_32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_LE_32, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_LE_32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_LE_32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_DTPMOD32, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_DTPMOD32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_DTPMOD32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_DTPOFF32, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_DTPOFF32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_DTPOFF32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_TPOFF32, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_TPOFF32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_TPOFF32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_SIZE32, 0, 2, 32, false, 0, complain_overflow_unsigned, + HOWTO(R_386_SIZE32, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_SIZE32", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_TLS_GOTDESC, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_GOTDESC, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_GOTDESC", true, 0xffffffff, 0xffffffff, false), HOWTO(R_386_TLS_DESC_CALL, 0, 3, 0, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_DESC_CALL", false, 0, 0, false), - HOWTO(R_386_TLS_DESC, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_TLS_DESC, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_TLS_DESC", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_IRELATIVE, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_IRELATIVE, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_IRELATIVE", true, 0xffffffff, 0xffffffff, false), - HOWTO(R_386_GOT32X, 0, 2, 32, false, 0, complain_overflow_bitfield, + HOWTO(R_386_GOT32X, 0, 2, 32, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_386_GOT32X", true, 0xffffffff, 0xffffffff, false), diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c index 840555c2000..83a749e6ddc 100644 --- a/bfd/elf64-x86-64.c +++ b/bfd/elf64-x86-64.c @@ -47,7 +47,7 @@ static reloc_howto_type x86_64_elf_howto_table[] = HOWTO(R_X86_64_NONE, 0, 3, 0, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_NONE", false, 0x00000000, 0x00000000, false), - HOWTO(R_X86_64_64, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_64, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_64", false, MINUS_ONE, MINUS_ONE, false), HOWTO(R_X86_64_PC32, 0, 2, 32, true, 0, complain_overflow_signed, @@ -62,13 +62,13 @@ static reloc_howto_type x86_64_elf_howto_table[] = HOWTO(R_X86_64_COPY, 0, 2, 32, false, 0, complain_overflow_bitfield, bfd_elf_generic_reloc, "R_X86_64_COPY", false, 0xffffffff, 0xffffffff, false), - HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_GLOB_DAT, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_GLOB_DAT", false, MINUS_ONE, MINUS_ONE, false), - HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_JUMP_SLOT, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_JUMP_SLOT", false, MINUS_ONE, MINUS_ONE, false), - HOWTO(R_X86_64_RELATIVE, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_RELATIVE, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_RELATIVE", false, MINUS_ONE, MINUS_ONE, false), HOWTO(R_X86_64_GOTPCREL, 0, 2, 32, true, 0, complain_overflow_signed, @@ -88,13 +88,13 @@ static reloc_howto_type x86_64_elf_howto_table[] = bfd_elf_generic_reloc, "R_X86_64_8", false, 0xff, 0xff, false), HOWTO(R_X86_64_PC8, 0, 0, 8, true, 0, complain_overflow_signed, bfd_elf_generic_reloc, "R_X86_64_PC8", false, 0xff, 0xff, true), - HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_DTPMOD64, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_DTPMOD64", false, MINUS_ONE, MINUS_ONE, false), - HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_DTPOFF64, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_DTPOFF64", false, MINUS_ONE, MINUS_ONE, false), - HOWTO(R_X86_64_TPOFF64, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_TPOFF64, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_TPOFF64", false, MINUS_ONE, MINUS_ONE, false), HOWTO(R_X86_64_TLSGD, 0, 2, 32, true, 0, complain_overflow_signed, @@ -112,10 +112,10 @@ static reloc_howto_type x86_64_elf_howto_table[] = HOWTO(R_X86_64_TPOFF32, 0, 2, 32, false, 0, complain_overflow_signed, bfd_elf_generic_reloc, "R_X86_64_TPOFF32", false, 0xffffffff, 0xffffffff, false), - HOWTO(R_X86_64_PC64, 0, 4, 64, true, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_PC64, 0, 4, 64, true, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_PC64", false, MINUS_ONE, MINUS_ONE, true), - HOWTO(R_X86_64_GOTOFF64, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_GOTOFF64, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_GOTOFF64", false, MINUS_ONE, MINUS_ONE, false), HOWTO(R_X86_64_GOTPC32, 0, 2, 32, true, 0, complain_overflow_signed, @@ -139,7 +139,7 @@ static reloc_howto_type x86_64_elf_howto_table[] = HOWTO(R_X86_64_SIZE32, 0, 2, 32, false, 0, complain_overflow_unsigned, bfd_elf_generic_reloc, "R_X86_64_SIZE32", false, 0xffffffff, 0xffffffff, false), - HOWTO(R_X86_64_SIZE64, 0, 4, 64, false, 0, complain_overflow_unsigned, + HOWTO(R_X86_64_SIZE64, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_SIZE64", false, MINUS_ONE, MINUS_ONE, false), HOWTO(R_X86_64_GOTPC32_TLSDESC, 0, 2, 32, true, 0, @@ -151,13 +151,13 @@ static reloc_howto_type x86_64_elf_howto_table[] = "R_X86_64_TLSDESC_CALL", false, 0, 0, false), HOWTO(R_X86_64_TLSDESC, 0, 4, 64, false, 0, - complain_overflow_bitfield, bfd_elf_generic_reloc, + complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_TLSDESC", false, MINUS_ONE, MINUS_ONE, false), - HOWTO(R_X86_64_IRELATIVE, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_IRELATIVE, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_IRELATIVE", false, MINUS_ONE, MINUS_ONE, false), - HOWTO(R_X86_64_RELATIVE64, 0, 4, 64, false, 0, complain_overflow_bitfield, + HOWTO(R_X86_64_RELATIVE64, 0, 4, 64, false, 0, complain_overflow_dont, bfd_elf_generic_reloc, "R_X86_64_RELATIVE64", false, MINUS_ONE, MINUS_ONE, false), HOWTO(R_X86_64_PC32_BND, 0, 2, 32, true, 0, complain_overflow_signed, -- 2.30.2