From ee1a066d1b41d82c2e6a67fc749fef7c2e8868bf Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Fri, 31 Jul 2026 07:00:52 +0800 Subject: [PATCH] x86: Disallow ".long foo@PLT - .L4" for PLT32 relocation Disallow ".long foo@PLT - .L4" and only allow ".slong foo@PLT - .L4" for PLT32 relocation. gas/ PR gas/34423 * config/tc-i386.c (cons_slong): New. (x86_cons): Return BFD_RELOC_X86_64_PC32_TO_PLT32 or BFD_RELOC_386_PC32_TO_PLT32 only if cons_slong is true. (signed_cons): Set cons_slong to true before calling cons and set it to false afterwards. (tc_gen_reloc): Update BFD_RELOC_X86_64_PC32_TO_PLT32 comments. * testsuite/gas/i386/ilp32/reloc64.l: Revert commit 53902b30c66. * testsuite/gas/i386/ilp32/reloc64.s: Likewise. * testsuite/gas/i386/reloc32.l: Likewise. * testsuite/gas/i386/reloc32.s: Likewise. * testsuite/gas/i386/reloc64.l: Likewise. * testsuite/gas/i386/plt.s: Replace .long with .slong. * testsuite/gas/i386/x86-64-jump-table.s: Likewise. ld/ PR gas/34423 * testsuite/ld-x86-64/x86-64-jump-table.s: Replace .long with .slong. Signed-off-by: H.J. Lu --- gas/config/tc-i386.c | 12 +++++++++--- gas/testsuite/gas/i386/ilp32/reloc64.l | 3 ++- gas/testsuite/gas/i386/ilp32/reloc64.s | 2 +- gas/testsuite/gas/i386/plt.s | 8 ++++---- gas/testsuite/gas/i386/reloc32.l | 4 ++-- gas/testsuite/gas/i386/reloc32.s | 2 +- gas/testsuite/gas/i386/reloc64.l | 3 ++- gas/testsuite/gas/i386/reloc64.s | 2 +- gas/testsuite/gas/i386/x86-64-jump-table.s | 10 +++++----- ld/testsuite/ld-x86-64/x86-64-jump-table.s | 10 +++++----- 10 files changed, 32 insertions(+), 24 deletions(-) diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c index 67badd29298..b61e1eb49e6 100644 --- a/gas/config/tc-i386.c +++ b/gas/config/tc-i386.c @@ -13374,6 +13374,10 @@ output_imm (fragS *insn_start_frag, offsetT insn_start_off) reloc is needed. We use this hook to get the correct .got reloc. */ static int cons_sign = -1; +/* This hook is used by x86_cons to allow ".slong foo@PLT - .L4", but + not ".long foo@PLT - .L4". */ +static bool cons_slong = false; + void x86_cons_fix_new (fragS *frag, unsigned int off, unsigned int len, expressionS *exp, bfd_reloc_code_real_type r) @@ -13553,10 +13557,10 @@ x86_cons (expressionS *exp, int size) || got_reloc == BFD_RELOC_32_PLT_PCREL) && exp->X_op != O_symbol) { - /* Allow directives like ".long foo@PLT - .L4". + /* Allow directives like ".slong foo@PLT - .L4". BFD_RELOC_X86_64_PC32_TO_PLT32 has an explicit addend and BFD_RELOC_386_PC32_TO_PLT32 has an implicit addend. */ - if (size == 4 && exp->X_op == O_subtract) + if (cons_slong && size == 4 && exp->X_op == O_subtract) got_reloc = (object_64bit ? BFD_RELOC_X86_64_PC32_TO_PLT32 : BFD_RELOC_386_PC32_TO_PLT32); @@ -13592,7 +13596,9 @@ signed_cons (int size) { if (object_64bit) cons_sign = 1; + cons_slong = true; cons (size); + cons_slong = false; cons_sign = -1; } @@ -18770,7 +18776,7 @@ tc_gen_reloc (asection *section ATTRIBUTE_UNUSED, fixS *fixp) rel->addend = fixp->fx_offset - fixp->fx_size; break; case BFD_RELOC_X86_64_PC32_TO_PLT32: - /* This came from a directive like ".long foo@PLT - .L4". + /* This came from a directive like ".slong foo@PLT - .L4". Generate R_X86_64_PLT32 with addend computed like R_X86_64_PC32 so that PLT entry is used to resolve this PC32 relocation. */ diff --git a/gas/testsuite/gas/i386/ilp32/reloc64.l b/gas/testsuite/gas/i386/ilp32/reloc64.l index 08c2702cdb7..14a111d763f 100644 --- a/gas/testsuite/gas/i386/ilp32/reloc64.l +++ b/gas/testsuite/gas/i386/ilp32/reloc64.l @@ -103,6 +103,8 @@ .*:176: Info: .* .*:3: Error: .* .*:177: Info: .* +.*:3: Error: .* +.*:190: Info: .* .*:193: Error: .* too large for field of 4 bytes at .* .*:194: Error: .* too large for field of 4 bytes at .* .*:195: Error: .* too large for field of 4 bytes at .* @@ -111,7 +113,6 @@ .*:197: Error: .* too large for field of 1 byte at .* .*:198: Error: .* too large for field of 2 bytes at .* .*:198: Error: .* too large for field of 1 byte at .* -.*:190: Error: can't resolve xtrn - _start .*:201: Error: .* too large for field of 4 bytes at .* .*:202: Error: .* too large for field of 2 bytes at .* .*:203: Error: .* too large for field of 2 bytes at .* diff --git a/gas/testsuite/gas/i386/ilp32/reloc64.s b/gas/testsuite/gas/i386/ilp32/reloc64.s index a4ccdb29916..db2d2acdf5d 100644 --- a/gas/testsuite/gas/i386/ilp32/reloc64.s +++ b/gas/testsuite/gas/i386/ilp32/reloc64.s @@ -187,7 +187,7 @@ bad .byte xtrn@tpoff .quad xtrn - 0x80000000 .long xtrn@got - 4 .long xtrn@got + 4 -bad .long xtrn@plt - _start +bad .long xtrn@plt - . .text bad add $x+0x123456789, %rax diff --git a/gas/testsuite/gas/i386/plt.s b/gas/testsuite/gas/i386/plt.s index c854c3fe739..5274b6c5a5f 100644 --- a/gas/testsuite/gas/i386/plt.s +++ b/gas/testsuite/gas/i386/plt.s @@ -1,7 +1,7 @@ .section .rodata .L4: - .long foo1@PLT - .L4 - .long foo2@PLT - .L4 - .long foo3@PLT - .L4 - .long foo4@PLT - .L4 + .slong foo1@PLT - .L4 + .slong foo2@PLT - .L4 + .slong foo3@PLT - .L4 + .slong foo4@PLT - .L4 diff --git a/gas/testsuite/gas/i386/reloc32.l b/gas/testsuite/gas/i386/reloc32.l index 31c71a0be28..71c65212dc9 100644 --- a/gas/testsuite/gas/i386/reloc32.l +++ b/gas/testsuite/gas/i386/reloc32.l @@ -131,6 +131,6 @@ .*:160: Info: .* .*:3: Error: .* .*:161: Info: .* -.*:56: Error: .* -.*:164: Error: .* +.*:3: Error: .* +.*:164: Info: .* #pass diff --git a/gas/testsuite/gas/i386/reloc32.s b/gas/testsuite/gas/i386/reloc32.s index 0ba69eae4d0..5616cd57e3f 100644 --- a/gas/testsuite/gas/i386/reloc32.s +++ b/gas/testsuite/gas/i386/reloc32.s @@ -161,7 +161,7 @@ bad .byte xtrn@ntpoff bad .byte xtrn@tpoff .long xtrn@got + 4 .long xtrn@got - 4 -bad .long xtrn@plt - _start +bad .long xtrn@plt - . .text movl $ptr@PLT, %eax diff --git a/gas/testsuite/gas/i386/reloc64.l b/gas/testsuite/gas/i386/reloc64.l index d84d9042958..c60c45d139a 100644 --- a/gas/testsuite/gas/i386/reloc64.l +++ b/gas/testsuite/gas/i386/reloc64.l @@ -163,4 +163,5 @@ .*:219: Info: .* .*:3: Error: .* .*:220: Info: .* -.*:227: Error: can't resolve xtrn - ptr +.*:3: Error: .* +.*:227: Info: .* diff --git a/gas/testsuite/gas/i386/reloc64.s b/gas/testsuite/gas/i386/reloc64.s index f248964813f..5c0f4136a09 100644 --- a/gas/testsuite/gas/i386/reloc64.s +++ b/gas/testsuite/gas/i386/reloc64.s @@ -224,7 +224,7 @@ bad .byte xtrn@gotplt mov xtrn(,%ebx), %eax vgatherdps %xmm2, xtrn(,%xmm1), %xmm0 addr32 vgatherdps %xmm2, xtrn(,%xmm1), %xmm0 -bad .long xtrn@plt - ptr +bad .long xtrn@plt - . .text movabs $ptr@GOT, %rax diff --git a/gas/testsuite/gas/i386/x86-64-jump-table.s b/gas/testsuite/gas/i386/x86-64-jump-table.s index aefffad8f65..f9957630b38 100644 --- a/gas/testsuite/gas/i386/x86-64-jump-table.s +++ b/gas/testsuite/gas/i386/x86-64-jump-table.s @@ -23,9 +23,9 @@ foo: .section .rodata .p2align 2 .L4: - .long bar0@plt-.L4 - .long bar1@PLT-.L4 - .long .Lbar2-.L4 - .long bar3@PLT-.L4 - .long bar4@plt-.L4 + .slong bar0@plt-.L4 + .slong bar1@PLT-.L4 + .slong .Lbar2-.L4 + .slong bar3@PLT-.L4 + .slong bar4@plt-.L4 .section .note.GNU-stack,"",@progbits diff --git a/ld/testsuite/ld-x86-64/x86-64-jump-table.s b/ld/testsuite/ld-x86-64/x86-64-jump-table.s index bd06f714469..84049d879bf 100644 --- a/ld/testsuite/ld-x86-64/x86-64-jump-table.s +++ b/ld/testsuite/ld-x86-64/x86-64-jump-table.s @@ -22,9 +22,9 @@ foo: .section .rodata .p2align 2 .L4: - .long bar0@plt-.L4 - .long bar1@PLT-.L4 - .long .Lbar2-.L4 - .long bar3@PLT-.L4 - .long bar4@plt-.L4 + .slong bar0@plt-.L4 + .slong bar1@PLT-.L4 + .slong .Lbar2-.L4 + .slong bar3@PLT-.L4 + .slong bar4@plt-.L4 .section .note.GNU-stack,"",@progbits -- 2.55.0