diff options
Diffstat (limited to 'subx')
| -rw-r--r-- | subx/012elf.cc | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/subx/012elf.cc b/subx/012elf.cc index 7bdbc548..85eb406a 100644 --- a/subx/012elf.cc +++ b/subx/012elf.cc @@ -57,11 +57,14 @@ void load_elf_contents(uint8_t* elf_contents, size_t size, int argc, char* argv[ // unused: e_shnum // unused: e_shstrndx + set<uint32_t> overlap; // to detect overlapping segments for (size_t i = 0; i < e_phnum; ++i) - load_segment_from_program_header(elf_contents, i, size, e_phoff + i*e_phentsize, e_ehsize); + load_segment_from_program_header(elf_contents, i, size, e_phoff + i*e_phentsize, e_ehsize, overlap); // initialize code and stack + assert(overlap.find(STACK_SEGMENT) == overlap.end()); Mem.push_back(vma(STACK_SEGMENT)); + assert(overlap.find(AFTER_STACK) == overlap.end()); Reg[ESP].u = AFTER_STACK; Reg[EBP].u = 0; EIP = e_entry; @@ -74,6 +77,7 @@ void load_elf_contents(uint8_t* elf_contents, size_t size, int argc, char* argv[ for (int i = argc-1; i >= /*skip 'subx_bin' and 'run'*/2; --i) { push(argv_data); for (size_t j = 0; j <= strlen(argv[i]); ++j) { + assert(overlap.find(argv_data) == overlap.end()); // don't bother comparing ARGV and STACK write_mem_u8(argv_data, argv[i][j]); argv_data += sizeof(char); assert(argv_data < ARGV_DATA_SEGMENT + SEGMENT_SIZE); @@ -89,7 +93,7 @@ void push(uint32_t val) { write_mem_u32(Reg[ESP].u, val); } -void load_segment_from_program_header(uint8_t* elf_contents, int segment_index, size_t size, uint32_t offset, uint32_t e_ehsize) { +void load_segment_from_program_header(uint8_t* elf_contents, int segment_index, size_t size, uint32_t offset, uint32_t e_ehsize, set<uint32_t>& overlap) { uint32_t p_type = u32_in(&elf_contents[offset]); trace(90, "load") << "program header at offset " << offset << ": type " << p_type << end(); if (p_type != 1) { @@ -114,8 +118,11 @@ void load_segment_from_program_header(uint8_t* elf_contents, int segment_index, trace(90, "load") << "blitting file offsets (" << p_offset << ", " << (p_offset+p_filesz) << ") to addresses (" << p_vaddr << ", " << (p_vaddr+p_memsz) << ')' << end(); if (size > p_memsz) size = p_memsz; Mem.push_back(vma(p_vaddr)); - for (size_t i = 0; i < p_filesz; ++i) + for (size_t i = 0; i < p_filesz; ++i) { + assert(overlap.find(p_vaddr+i) == overlap.end()); write_mem_u8(p_vaddr+i, elf_contents[p_offset+i]); + overlap.insert(p_vaddr+i); + } if (segment_index == 0 && End_of_program < p_vaddr+p_memsz) End_of_program = p_vaddr+p_memsz; } |