Author: Peter Collingbourne Date: 2021-02-11T15:05:18-08:00 New Revision: c314f5ede8249ef20fff1de45c2c31156b1950d4
URL: https://github.com/llvm/llvm-project/commit/c314f5ede8249ef20fff1de45c2c31156b1950d4 DIFF: https://github.com/llvm/llvm-project/commit/c314f5ede8249ef20fff1de45c2c31156b1950d4.diff LOG: ObjectFileELF: Test whether reloc_header is non-null instead of asserting. It is possible for the GetSectionHeaderByIndex lookup to fail because the previous FindSectionContainingFileAddress lookup found a segment instead of a section. This is possible if the binary does not have a PLT (which means that lld will in some circumstances set DT_JMPREL to 0, which is typically an address that is part of the ELF headers and not in a section) and may also be possible if the section headers have been stripped. To handle this possibility, replace the assert with an if. Differential Revision: https://reviews.llvm.org/D93438 Added: lldb/test/Shell/ObjectFile/ELF/null-jmprel.yaml Modified: lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp Removed: ################################################################################ diff --git a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp index cad9ce218b10..df0586367832 100644 --- a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp +++ b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp @@ -2770,14 +2770,14 @@ Symtab *ObjectFileELF::GetSymtab() { user_id_t reloc_id = reloc_section->GetID(); const ELFSectionHeaderInfo *reloc_header = GetSectionHeaderByIndex(reloc_id); - assert(reloc_header); + if (reloc_header) { + if (m_symtab_up == nullptr) + m_symtab_up = + std::make_unique<Symtab>(reloc_section->GetObjectFile()); - if (m_symtab_up == nullptr) - m_symtab_up = - std::make_unique<Symtab>(reloc_section->GetObjectFile()); - - ParseTrampolineSymbols(m_symtab_up.get(), symbol_id, reloc_header, - reloc_id); + ParseTrampolineSymbols(m_symtab_up.get(), symbol_id, reloc_header, + reloc_id); + } } } diff --git a/lldb/test/Shell/ObjectFile/ELF/null-jmprel.yaml b/lldb/test/Shell/ObjectFile/ELF/null-jmprel.yaml new file mode 100644 index 000000000000..ae151ba8cdc1 --- /dev/null +++ b/lldb/test/Shell/ObjectFile/ELF/null-jmprel.yaml @@ -0,0 +1,148 @@ +# RUN: yaml2obj %s -o %t +# RUN: lldb-test symbols %t | FileCheck %s + +# CHECK: _DYNAMIC +# CHECK: _start + +--- !ELF +FileHeader: + Class: ELFCLASS64 + Data: ELFDATA2LSB + Type: ET_DYN + Machine: EM_X86_64 + Entry: 0x1000 +ProgramHeaders: + - Type: PT_PHDR + Flags: [ PF_R ] + VAddr: 0x40 + Align: 0x8 + - Type: PT_LOAD + Flags: [ PF_R ] + FirstSec: .dynsym + LastSec: .dynstr + Align: 0x1000 + - Type: PT_LOAD + Flags: [ PF_X, PF_R ] + FirstSec: .text + LastSec: .text + VAddr: 0x1000 + Align: 0x1000 + - Type: PT_LOAD + Flags: [ PF_W, PF_R ] + FirstSec: .data + LastSec: .bss + VAddr: 0x2000 + Align: 0x1000 + - Type: PT_DYNAMIC + Flags: [ PF_W, PF_R ] + FirstSec: .data + LastSec: .dynamic + VAddr: 0x2000 + Align: 0x8 + - Type: PT_GNU_RELRO + Flags: [ PF_R ] + FirstSec: .data + LastSec: .bss + VAddr: 0x2000 + - Type: PT_GNU_STACK + Flags: [ PF_W, PF_R ] + Align: 0x0 +Sections: + - Name: .dynsym + Type: SHT_DYNSYM + Flags: [ SHF_ALLOC ] + Address: 0x1C8 + Link: .dynstr + AddressAlign: 0x8 + EntSize: 0x18 + - Name: .gnu.hash + Type: SHT_GNU_HASH + Flags: [ SHF_ALLOC ] + Address: 0x1F8 + Link: .dynsym + AddressAlign: 0x8 + Header: + SymNdx: 0x1 + Shift2: 0x6 + BloomFilter: [ 0x4000000000100 ] + HashBuckets: [ 0x1 ] + HashValues: [ 0xEDDB6233 ] + - Name: .hash + Type: SHT_HASH + Flags: [ SHF_ALLOC ] + Address: 0x218 + Link: .dynsym + AddressAlign: 0x4 + Bucket: [ 1, 0 ] + Chain: [ 0, 0 ] + - Name: .dynstr + Type: SHT_STRTAB + Flags: [ SHF_ALLOC ] + Address: 0x230 + AddressAlign: 0x1 + - Name: .text + Type: SHT_PROGBITS + Flags: [ SHF_ALLOC, SHF_EXECINSTR ] + Address: 0x1000 + AddressAlign: 0x1 + Offset: 0x1000 + Content: C3 + - Name: .data + Type: SHT_PROGBITS + Flags: [ SHF_WRITE, SHF_ALLOC ] + Address: 0x2000 + AddressAlign: 0x1 + Offset: 0x2000 + - Name: .dynamic + Type: SHT_DYNAMIC + Flags: [ SHF_WRITE, SHF_ALLOC ] + Address: 0x2000 + Link: .dynstr + AddressAlign: 0x8 + Entries: + - Tag: DT_SYMTAB + Value: 0x1C8 + - Tag: DT_SYMENT + Value: 0x18 + - Tag: DT_STRTAB + Value: 0x230 + - Tag: DT_STRSZ + Value: 0x8 + - Tag: DT_GNU_HASH + Value: 0x1F8 + - Tag: DT_HASH + Value: 0x218 + - Tag: DT_JMPREL + Value: 0x0 + - Tag: DT_PLTRELSZ + Value: 0x0 + - Tag: DT_NULL + Value: 0x0 + - Name: .bss + Type: SHT_NOBITS + Flags: [ SHF_WRITE, SHF_ALLOC ] + Address: 0x3000 + AddressAlign: 0x1 + - Name: .comment + Type: SHT_PROGBITS + Flags: [ SHF_MERGE, SHF_STRINGS ] + AddressAlign: 0x1 + EntSize: 0x1 + Content: 4C696E6B65723A204C4C4420372E302E3000 +Symbols: + - Name: _DYNAMIC + Section: .dynamic + Value: 0x2000 + Other: [ STV_HIDDEN ] + - Name: _start + Type: STT_FUNC + Section: .text + Binding: STB_GLOBAL + Value: 0x1000 +DynamicSymbols: + - Name: _start + Type: STT_FUNC + Section: .text + Binding: STB_GLOBAL + Value: 0x1000 +... _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
