From b44ee3a8cf21294eeb079ffbada7eeb559a9c6b4 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Sat, 1 Dec 2018 05:42:33 -0800 Subject: [PATCH] x86: Delay setting the iplt section alignment Delay setting its alignment until we know it is non-empty. Otherwise an empty iplt section may change vma and lma of the following sections, which triggers moving dot of the following section backwards, resulting in a warning and section lma not being set properly. It later leads to a "File truncated" error. bfd/ PR ld/23930 * elfxx-x86.c (_bfd_x86_elf_size_dynamic_sections): Update the iplt section alignment if it is non-empty. (_bfd_x86_elf_link_setup_gnu_properties): Set plt.iplt_alignment and delay setting the iplt section alignment. * elfxx-x86.h (elf_x86_plt_layout): Add iplt_alignment. ld/ PR ld/23930 * testsuite/ld-i386/i386.exp: Run pr23930. * testsuite/ld-i386/pr23930.d: New file. * testsuite/ld-x86-64/pr23930-32.t: Likewise. * testsuite/ld-x86-64/pr23930-x32.d: Likewise. * testsuite/ld-x86-64/pr23930.d: Likewise. * testsuite/ld-x86-64/pr23930.t: Likewise. * testsuite/ld-x86-64/pr23930a.s: Likewise. * testsuite/ld-x86-64/pr23930b.s: Likewise. * testsuite/ld-x86-64/x86-64.exp: Run pr23930 and pr23930-x32. --- bfd/ChangeLog | 9 +++++++++ bfd/elfxx-x86.c | 30 +++++++++++++++++++++++------- bfd/elfxx-x86.h | 3 +++ ld/ChangeLog | 13 +++++++++++++ ld/testsuite/ld-i386/i386.exp | 1 + ld/testsuite/ld-i386/pr23930.d | 11 +++++++++++ ld/testsuite/ld-x86-64/pr23930-32.t | 10 ++++++++++ ld/testsuite/ld-x86-64/pr23930-x32.d | 11 +++++++++++ ld/testsuite/ld-x86-64/pr23930.d | 11 +++++++++++ ld/testsuite/ld-x86-64/pr23930.t | 10 ++++++++++ ld/testsuite/ld-x86-64/pr23930a.s | 7 +++++++ ld/testsuite/ld-x86-64/pr23930b.s | 14 ++++++++++++++ ld/testsuite/ld-x86-64/x86-64.exp | 2 ++ 13 files changed, 125 insertions(+), 7 deletions(-) create mode 100644 ld/testsuite/ld-i386/pr23930.d create mode 100644 ld/testsuite/ld-x86-64/pr23930-32.t create mode 100644 ld/testsuite/ld-x86-64/pr23930-x32.d create mode 100644 ld/testsuite/ld-x86-64/pr23930.d create mode 100644 ld/testsuite/ld-x86-64/pr23930.t create mode 100644 ld/testsuite/ld-x86-64/pr23930a.s create mode 100644 ld/testsuite/ld-x86-64/pr23930b.s diff --git a/bfd/ChangeLog b/bfd/ChangeLog index e0eb155..3210b0c 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,12 @@ +2018-12-01 H.J. Lu + + PR ld/23930 + * elfxx-x86.c (_bfd_x86_elf_size_dynamic_sections): Update + the iplt section alignment if it is non-empty. + (_bfd_x86_elf_link_setup_gnu_properties): Set plt.iplt_alignment + and delay setting the iplt section alignment. + * elfxx-x86.h (elf_x86_plt_layout): Add iplt_alignment. + 2018-11-30 Nick Clifton PR 23942 diff --git a/bfd/elfxx-x86.c b/bfd/elfxx-x86.c index 05f5c6a..40aac66 100644 --- a/bfd/elfxx-x86.c +++ b/bfd/elfxx-x86.c @@ -1275,6 +1275,14 @@ _bfd_x86_elf_size_dynamic_sections (bfd *output_bfd, if ((s->flags & SEC_HAS_CONTENTS) == 0) continue; + /* NB: Initially, the iplt section has minimal alignment to + avoid moving dot of the following section backwards when + it is empty. Update its section alignment now since it + is non-empty. */ + if (s == htab->elf.iplt) + bfd_set_section_alignment (s->owner, s, + htab->plt.iplt_alignment); + /* Allocate memory for the section contents. We use bfd_zalloc here in case unused entries are not reclaimed before the section's contents are written out. This should not happen, @@ -2907,15 +2915,23 @@ error_alignment: } } - if (normal_target) + /* The .iplt section is used for IFUNC symbols in static + executables. */ + sec = htab->elf.iplt; + if (sec != NULL) { - /* The .iplt section is used for IFUNC symbols in static - executables. */ - sec = htab->elf.iplt; - if (sec != NULL - && !bfd_set_section_alignment (sec->owner, sec, - plt_alignment)) + /* NB: Delay setting its alignment until we know it is non-empty. + Otherwise an empty iplt section may change vma and lma of the + following sections, which triggers moving dot of the following + section backwards, resulting in a warning and section lma not + being set properly. It later leads to a "File truncated" + error. */ + if (!bfd_set_section_alignment (sec->owner, sec, 0)) goto error_alignment; + + htab->plt.iplt_alignment = (normal_target + ? plt_alignment + : bed->plt_alignment); } return pbfd; diff --git a/bfd/elfxx-x86.h b/bfd/elfxx-x86.h index 9648438..d153623 100644 --- a/bfd/elfxx-x86.h +++ b/bfd/elfxx-x86.h @@ -389,6 +389,9 @@ struct elf_x86_plt_layout This is only used for x86-64. */ unsigned int plt_got_insn_size; + /* Alignment of the .iplt section. */ + unsigned int iplt_alignment; + /* .eh_frame covering the .plt section. */ const bfd_byte *eh_frame_plt; unsigned int eh_frame_plt_size; diff --git a/ld/ChangeLog b/ld/ChangeLog index e203edc..80fd06c 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,16 @@ +2018-12-01 H.J. Lu + + PR ld/23930 + * testsuite/ld-i386/i386.exp: Run pr23930. + * testsuite/ld-i386/pr23930.d: New file. + * testsuite/ld-x86-64/pr23930-32.t: Likewise. + * testsuite/ld-x86-64/pr23930-x32.d: Likewise. + * testsuite/ld-x86-64/pr23930.d: Likewise. + * testsuite/ld-x86-64/pr23930.t: Likewise. + * testsuite/ld-x86-64/pr23930a.s: Likewise. + * testsuite/ld-x86-64/pr23930b.s: Likewise. + * testsuite/ld-x86-64/x86-64.exp: Run pr23930 and pr23930-x32. +--- 2018-11-30 Alan Modra * testsuite/ld-powerpc/pr23937.d, diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp index 76577c4..f86a54d 100644 --- a/ld/testsuite/ld-i386/i386.exp +++ b/ld/testsuite/ld-i386/i386.exp @@ -482,6 +482,7 @@ run_dump_test "pr23486b" run_dump_test "pr23486c" run_dump_test "pr23486d" run_dump_test "pr23854" +run_dump_test "pr23930" if { !([istarget "i?86-*-linux*"] || [istarget "i?86-*-gnu*"] diff --git a/ld/testsuite/ld-i386/pr23930.d b/ld/testsuite/ld-i386/pr23930.d new file mode 100644 index 0000000..e9da510 --- /dev/null +++ b/ld/testsuite/ld-i386/pr23930.d @@ -0,0 +1,11 @@ +#source: ../ld-x86-64/pr23930a.s +#source: ../ld-x86-64/pr23930b.s +#as: --32 +#ld: -m elf_i386 -z separate-code -z norelro -T ../ld-x86-64/pr23930-32.t +#objdump: --disassemble=main + +#... +[a-f0-9]+
: +[a-f0-9]+: 31 c0 xor %eax,%eax +[a-f0-9]+: c3 ret +#pass diff --git a/ld/testsuite/ld-x86-64/pr23930-32.t b/ld/testsuite/ld-x86-64/pr23930-32.t new file mode 100644 index 0000000..29b5309 --- /dev/null +++ b/ld/testsuite/ld-x86-64/pr23930-32.t @@ -0,0 +1,10 @@ +PHDRS { + text PT_LOAD; +} + +SECTIONS +{ + . = (0x8000000f + ALIGN(0x1000000, 0x1000000)); + .text : AT(ADDR(.text) - 0x8000000f) { + } :text +} diff --git a/ld/testsuite/ld-x86-64/pr23930-x32.d b/ld/testsuite/ld-x86-64/pr23930-x32.d new file mode 100644 index 0000000..b01d2b9 --- /dev/null +++ b/ld/testsuite/ld-x86-64/pr23930-x32.d @@ -0,0 +1,11 @@ +#source: pr23930a.s +#source: pr23930b.s +#as: --x32 +#ld: -m elf32_x86_64 -z separate-code -z norelro -T pr23930-32.t +#objdump: --disassemble=main + +#... +[a-f0-9]+
: +[a-f0-9]+: 31 c0 xor %eax,%eax +[a-f0-9]+: c3 retq +#pass diff --git a/ld/testsuite/ld-x86-64/pr23930.d b/ld/testsuite/ld-x86-64/pr23930.d new file mode 100644 index 0000000..c849b68 --- /dev/null +++ b/ld/testsuite/ld-x86-64/pr23930.d @@ -0,0 +1,11 @@ +#source: pr23930a.s +#source: pr23930b.s +#as: --64 +#ld: -m elf_x86_64 -z separate-code -z norelro -T pr23930.t +#objdump: --disassemble=main + +#... +[a-f0-9]+
: +[a-f0-9]+: 31 c0 xor %eax,%eax +[a-f0-9]+: c3 retq +#pass diff --git a/ld/testsuite/ld-x86-64/pr23930.t b/ld/testsuite/ld-x86-64/pr23930.t new file mode 100644 index 0000000..2255ed3 --- /dev/null +++ b/ld/testsuite/ld-x86-64/pr23930.t @@ -0,0 +1,10 @@ +PHDRS { + text PT_LOAD; +} + +SECTIONS +{ + . = (0xffffffff8000000f + ALIGN(0x1000000, 0x1000000)); + .text : AT(ADDR(.text) - 0xffffffff8000000f) { + } :text +} diff --git a/ld/testsuite/ld-x86-64/pr23930a.s b/ld/testsuite/ld-x86-64/pr23930a.s new file mode 100644 index 0000000..e1679a9 --- /dev/null +++ b/ld/testsuite/ld-x86-64/pr23930a.s @@ -0,0 +1,7 @@ + .text + .globl other + .type other, @function +other: + xorl %eax, %eax + ret + .size other, .-other diff --git a/ld/testsuite/ld-x86-64/pr23930b.s b/ld/testsuite/ld-x86-64/pr23930b.s new file mode 100644 index 0000000..e4859c7 --- /dev/null +++ b/ld/testsuite/ld-x86-64/pr23930b.s @@ -0,0 +1,14 @@ + .text + .globl orig + .type orig, @function +orig: + xorl %eax, %eax + ret + .size orig, .-orig + .section .text.startup,"ax",@progbits + .globl main + .type main, @function +main: + xorl %eax, %eax + ret + .size main, .-main diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp index 8e5348d..b51ad7c 100644 --- a/ld/testsuite/ld-x86-64/x86-64.exp +++ b/ld/testsuite/ld-x86-64/x86-64.exp @@ -422,6 +422,8 @@ run_dump_test "pr23486c-x32" run_dump_test "pr23486d" run_dump_test "pr23486d-x32" run_dump_test "pr23854" +run_dump_test "pr23930" +run_dump_test "pr23930-x32" if { ![istarget "x86_64-*-linux*"] && ![istarget "x86_64-*-nacl*"]} { return -- 2.7.4