From ab7fede88eddf004994f8769e3c7ac145628f5b4 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Tue, 18 Nov 2014 11:03:09 -0800 Subject: [PATCH] Check PC-relative offset overflow in PLT entry This patch checks PC-relative offset overflow in pushq instruction in x86-64 PLT entry. bfd/ PR ld/17618 * elf64-x86-64.c (elf_x86_64_finish_dynamic_symbol): Check PC-relative offset overflow in PLT entry. ld/testsuite/ PR ld/17618 * ld-x86-64/x86-64.exp: Run pr17618 for Linux target. * ld-x86-64/pr17618.d: New file. * ld-x86-64/pr17618.s: Likewise. --- bfd/ChangeLog | 6 ++++++ bfd/elf64-x86-64.c | 27 +++++++++++++++++++-------- ld/testsuite/ChangeLog | 8 ++++++++ ld/testsuite/ld-x86-64/pr17618.d | 4 ++++ ld/testsuite/ld-x86-64/pr17618.s | 18 ++++++++++++++++++ ld/testsuite/ld-x86-64/x86-64.exp | 7 +++++++ 6 files changed, 62 insertions(+), 8 deletions(-) create mode 100644 ld/testsuite/ld-x86-64/pr17618.d create mode 100644 ld/testsuite/ld-x86-64/pr17618.s diff --git a/bfd/ChangeLog b/bfd/ChangeLog index f606e1516b8..579cca27d58 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,9 @@ +2014-11-18 H.J. Lu + + PR ld/17618 + * elf64-x86-64.c (elf_x86_64_finish_dynamic_symbol): Check + PC-relative offset overflow in PLT entry. + 2014-11-18 Nick Clifton PR binutils/17512 diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c index 20f45a917c9..432ab588546 100644 --- a/bfd/elf64-x86-64.c +++ b/bfd/elf64-x86-64.c @@ -4749,6 +4749,8 @@ elf_x86_64_finish_dynamic_symbol (bfd *output_bfd, bfd_byte *loc; asection *plt, *gotplt, *relplt, *resolved_plt; const struct elf_backend_data *bed; + bfd_boolean gotplt_after_plt; + int32_t plt_got_pcrel_offset; /* When building a static executable, use .iplt, .igot.plt and .rela.iplt sections for STT_GNU_IFUNC symbols. */ @@ -4853,14 +4855,23 @@ elf_x86_64_finish_dynamic_symbol (bfd *output_bfd, /* Put offset the PC-relative instruction referring to the GOT entry, subtracting the size of that instruction. */ - bfd_put_32 (output_bfd, - (gotplt->output_section->vma - + gotplt->output_offset - + got_offset - - resolved_plt->output_section->vma - - resolved_plt->output_offset - - plt_offset - - plt_got_insn_size), + plt_got_pcrel_offset = (gotplt->output_section->vma + + gotplt->output_offset + + got_offset + - resolved_plt->output_section->vma + - resolved_plt->output_offset + - plt_offset + - plt_got_insn_size); + + /* Check PC-relative offset overflow in PLT entry. */ + gotplt_after_plt = (gotplt->output_section->vma + > resolved_plt->output_section->vma); + if ((gotplt_after_plt && plt_got_pcrel_offset < 0) + || (!gotplt_after_plt && plt_got_pcrel_offset > 0)) + info->callbacks->einfo (_("%F%B: PC-relative offset overflow in PLT entry for `%s'\n"), + output_bfd, h->root.root.string); + + bfd_put_32 (output_bfd, plt_got_pcrel_offset, resolved_plt->contents + plt_offset + plt_got_offset); /* Fill in the entry in the global offset table, initially this diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog index a8aa37dc05e..72b4bb97038 100644 --- a/ld/testsuite/ChangeLog +++ b/ld/testsuite/ChangeLog @@ -1,3 +1,11 @@ +2014-11-18 H.J. Lu + + PR ld/17618 + * ld-x86-64/x86-64.exp: Run pr17618 for Linux target. + + * ld-x86-64/pr17618.d: New file. + * ld-x86-64/pr17618.s: Likewise. + 2014-11-18 H.J. Lu * ld-x86-64/mpx.exp: Always run mpx3 and mpx4 tests in 64-bit. diff --git a/ld/testsuite/ld-x86-64/pr17618.d b/ld/testsuite/ld-x86-64/pr17618.d new file mode 100644 index 00000000000..e640b4044ec --- /dev/null +++ b/ld/testsuite/ld-x86-64/pr17618.d @@ -0,0 +1,4 @@ +#name: PLT PC-relative offset overflow check +#as: --64 +#ld: -shared -melf_x86_64 +#error: .*PC-relative offset overflow in PLT entry for `bar' diff --git a/ld/testsuite/ld-x86-64/pr17618.s b/ld/testsuite/ld-x86-64/pr17618.s new file mode 100644 index 00000000000..39102e07978 --- /dev/null +++ b/ld/testsuite/ld-x86-64/pr17618.s @@ -0,0 +1,18 @@ + .text + .globl foo + .type foo, @function +foo: + call bar@PLT + .size foo, .-foo + + .globl gap + .type gap, @function +gap: + jmp .L0 + .space 0x40000000, 0x90 +.L0: + jmp .L2 + .space 0x3fdfff14, 0x90 +.L2: + .size gap, .-gap + .section .note.GNU-stack,"",@progbits diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp index a9b68ff2133..7f09458d01f 100644 --- a/ld/testsuite/ld-x86-64/x86-64.exp +++ b/ld/testsuite/ld-x86-64/x86-64.exp @@ -333,3 +333,10 @@ if { [isnative] && [which $CC] != 0 } { {dummy.s} {{readelf {-s --wide} x86-64-x32.rd}} "x86-64-x32"} } } + +if { ![istarget "x86_64-*-linux*"]} { + return +} + +# Linux only tests +run_dump_test "pr17618" -- 2.30.2