diff --git a/lld/ELF/Relocations.cpp b/lld/ELF/Relocations.cpp index 4aa27b0a71bc1..2268121827f64 100644 --- a/lld/ELF/Relocations.cpp +++ b/lld/ELF/Relocations.cpp @@ -1687,6 +1687,17 @@ template void elf::scanRelocations(Ctx &ctx) { outerFn(); } +RelocationBaseSection &elf::getIRelativeSection(Ctx &ctx) { + // Prior to Android V, there was a bug that caused RELR relocations to be + // applied after packed relocations. This meant that resolvers referenced by + // IRELATIVE relocations in the packed relocation section would read + // unrelocated globals with RELR relocations when + // --pack-relative-relocs=android+relr is enabled. Work around this by placing + // IRELATIVE in .rela.plt. + return ctx.arg.androidPackDynRelocs ? *ctx.in.relaPlt + : *ctx.mainPart->relaDyn; +} + static bool handleNonPreemptibleIfunc(Ctx &ctx, Symbol &sym, uint16_t flags) { // Handle a reference to a non-preemptible ifunc. These are special in a // few ways: @@ -1736,17 +1747,9 @@ static bool handleNonPreemptibleIfunc(Ctx &ctx, Symbol &sym, uint16_t flags) { // original section/value pairs. For non-GOT non-PLT relocation case below, we // may alter section/value, so create a copy of the symbol to make // section/value fixed. - // - // Prior to Android V, there was a bug that caused RELR relocations to be - // applied after packed relocations. This meant that resolvers referenced by - // IRELATIVE relocations in the packed relocation section would read - // unrelocated globals with RELR relocations when - // --pack-relative-relocs=android+relr is enabled. Work around this by placing - // IRELATIVE in .rela.plt. auto *directSym = makeDefined(cast(sym)); directSym->allocateAux(ctx); - auto &dyn = - ctx.arg.androidPackDynRelocs ? *ctx.in.relaPlt : *ctx.mainPart->relaDyn; + auto &dyn = getIRelativeSection(ctx); addPltEntry(ctx, *ctx.in.iplt, *ctx.in.igotPlt, dyn, ctx.target->iRelativeRel, *directSym); sym.allocateAux(ctx); diff --git a/lld/ELF/Relocations.h b/lld/ELF/Relocations.h index 71cea0220e04c..7ca203257ea87 100644 --- a/lld/ELF/Relocations.h +++ b/lld/ELF/Relocations.h @@ -22,6 +22,7 @@ class Symbol; class InputSection; class InputSectionBase; class OutputSection; +class RelocationBaseSection; class SectionBase; // Represents a relocation type, such as R_X86_64_PC32 or R_ARM_THM_CALL. @@ -356,6 +357,8 @@ sortRels(Relocs> rels, return {}; } +RelocationBaseSection &getIRelativeSection(Ctx &ctx); + // Returns true if Expr refers a GOT entry. Note that this function returns // false for TLS variables even though they need GOT, because TLS variables uses // GOT differently than the regular variables. diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp index f10cc54c05a0c..49616fa03e63c 100644 --- a/lld/ELF/Writer.cpp +++ b/lld/ELF/Writer.cpp @@ -844,11 +844,15 @@ template void Writer::setReservedSymbolSections() { ctx.sym.globalOffsetTable->section = sec; } - // .rela_iplt_{start,end} mark the start and the end of .rel[a].dyn. - if (ctx.sym.relaIpltStart && ctx.mainPart->relaDyn->isNeeded()) { - ctx.sym.relaIpltStart->section = ctx.mainPart->relaDyn.get(); - ctx.sym.relaIpltEnd->section = ctx.mainPart->relaDyn.get(); - ctx.sym.relaIpltEnd->value = ctx.mainPart->relaDyn->getSize(); + // .rela_iplt_{start,end} mark the start and the end of the section containing + // IRELATIVE relocations. + if (ctx.sym.relaIpltStart) { + auto &dyn = getIRelativeSection(ctx); + if (dyn.isNeeded()) { + ctx.sym.relaIpltStart->section = &dyn; + ctx.sym.relaIpltEnd->section = &dyn; + ctx.sym.relaIpltEnd->value = dyn.getSize(); + } } PhdrEntry *last = nullptr; diff --git a/lld/test/ELF/pack-dyn-relocs-ifunc.s b/lld/test/ELF/pack-dyn-relocs-ifunc.s index 6168d06f99d9e..b6000df3d6160 100644 --- a/lld/test/ELF/pack-dyn-relocs-ifunc.s +++ b/lld/test/ELF/pack-dyn-relocs-ifunc.s @@ -47,3 +47,28 @@ _start: .globl bar bar: ret + +#--- c.s + +# RUN: llvm-mc -filetype=obj -triple=aarch64-linux-android c.s -o c.o +# RUN: ld.lld --pack-dyn-relocs=android c.o -o c +# RUN: llvm-readelf -sS c | FileCheck --check-prefix=STATIC %s + +# STATIC: .rela.plt RELA 0000000000200158 000158 000018 18 AI 0 5 8 +# STATIC: 0000000000200158 0 NOTYPE LOCAL HIDDEN 1 __rela_iplt_start +# STATIC: 0000000000200170 0 NOTYPE LOCAL HIDDEN 1 __rela_iplt_end + +.text +.type foo, %gnu_indirect_function +.globl foo +foo: + ret + +.globl _start +_start: + bl foo + +.data +.balign 8 +.quad __rela_iplt_start +.quad __rela_iplt_end