ladybird/Tests/LibELF/test-elf.cpp
Kenneth Myhra 4a57be824c Userland+Tests: Convert File::read_link() from String to ErrorOr<String>
This converts the return value of File::read_link() from String to
ErrorOr<String>.

The rest of the change is to support the potential of an Error being
returned and subsequent release of the value when no Error is returned.
Unfortunately at this stage none of the places affected can utililize
our TRY() macro.
2022-03-24 11:57:51 +01:00

306 lines
9.9 KiB
C++

/*
* Copyright (c) 2021, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibC/elf.h>
#include <LibCore/File.h>
#include <LibTest/TestCase.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
TEST_CASE(test_interp_header_tiny_p_filesz)
{
char buffer[0x2000];
auto& header = *(Elf32_Ehdr*)buffer;
header.e_ident[EI_MAG0] = ELFMAG0;
header.e_ident[EI_MAG1] = ELFMAG1;
header.e_ident[EI_MAG2] = ELFMAG2;
header.e_ident[EI_MAG3] = ELFMAG3;
header.e_ident[EI_CLASS] = ELFCLASS32;
header.e_ident[EI_DATA] = ELFDATA2LSB;
header.e_ident[EI_VERSION] = EV_CURRENT;
header.e_ident[EI_OSABI] = ELFOSABI_SYSV;
header.e_ident[EI_ABIVERSION] = 0;
header.e_type = ET_REL;
header.e_version = EV_CURRENT;
header.e_ehsize = sizeof(Elf32_Ehdr);
header.e_machine = EM_386;
header.e_shentsize = sizeof(Elf32_Shdr);
header.e_phnum = 1;
header.e_phoff = 52; // inaccurate
header.e_phentsize = sizeof(Elf32_Phdr); // inaccurate
header.e_shnum = 3; // inaccurate
header.e_shoff = 1024; // inaccurate
header.e_shstrndx = 2; // inaccurate
header.e_entry = 1024; // inaccurate
auto* ph = (Elf32_Phdr*)(&buffer[header.e_phoff]);
ph[0].p_flags = PF_R | PF_X;
ph[0].p_vaddr = 0x00d4;
ph[0].p_align = PAGE_SIZE;
ph[0].p_type = PT_INTERP;
ph[0].p_memsz = 0xffff0000;
ph[0].p_offset = 0x100;
// p_filesz (1 or less) to trigger crash
ph[0].p_filesz = 1;
char path[] = "/tmp/test-elf.XXXXXX";
auto fd = mkstemp(path);
EXPECT_NE(fd, -1);
EXPECT_EQ(fchmod(fd, 0700), 0);
int nwritten = write(fd, buffer, sizeof(buffer));
EXPECT(nwritten);
auto elf_path_or_error = Core::File::read_link(String::formatted("/proc/{}/fd/{}", getpid(), fd));
EXPECT(!elf_path_or_error.is_error());
auto elf_path = elf_path_or_error.release_value();
EXPECT(elf_path.characters());
int rc = execl(elf_path.characters(), "test-elf", nullptr);
EXPECT_EQ(rc, -1);
EXPECT_EQ(errno, 8);
EXPECT_EQ(unlink(path), 0);
}
TEST_CASE(test_interp_header_p_filesz_larger_than_p_memsz)
{
char buffer[0x2000];
auto& header = *(Elf32_Ehdr*)buffer;
header.e_ident[EI_MAG0] = ELFMAG0;
header.e_ident[EI_MAG1] = ELFMAG1;
header.e_ident[EI_MAG2] = ELFMAG2;
header.e_ident[EI_MAG3] = ELFMAG3;
header.e_ident[EI_CLASS] = ELFCLASS32;
header.e_ident[EI_DATA] = ELFDATA2LSB;
header.e_ident[EI_VERSION] = EV_CURRENT;
header.e_ident[EI_OSABI] = ELFOSABI_SYSV;
header.e_ident[EI_ABIVERSION] = 0;
header.e_type = ET_REL;
header.e_version = EV_CURRENT;
header.e_ehsize = sizeof(Elf32_Ehdr);
header.e_machine = EM_386;
header.e_shentsize = sizeof(Elf32_Shdr);
header.e_phnum = 1;
header.e_phoff = 52; // inaccurate
header.e_phentsize = sizeof(Elf32_Phdr); // inaccurate
header.e_shnum = 3; // inaccurate
header.e_shoff = 1024; // inaccurate
header.e_shstrndx = 2; // inaccurate
header.e_entry = 1024; // inaccurate
auto* ph = (Elf32_Phdr*)(&buffer[header.e_phoff]);
ph[0].p_flags = PF_R | PF_X;
ph[0].p_vaddr = 0x00d4;
ph[0].p_align = PAGE_SIZE;
ph[0].p_type = PT_INTERP;
ph[0].p_memsz = 0xffff0000;
ph[0].p_offset = 0x1000;
ph[0].p_filesz = 0x1000;
char path[] = "/tmp/test-elf.XXXXXX";
auto fd = mkstemp(path);
EXPECT_NE(fd, -1);
EXPECT_EQ(fchmod(fd, 0700), 0);
int nwritten = write(fd, buffer, sizeof(buffer));
EXPECT(nwritten);
auto elf_path_or_error = Core::File::read_link(String::formatted("/proc/{}/fd/{}", getpid(), fd));
EXPECT(!elf_path_or_error.is_error());
auto elf_path = elf_path_or_error.release_value();
EXPECT(elf_path.characters());
int rc = execl(elf_path.characters(), "test-elf", nullptr);
EXPECT_EQ(rc, -1);
EXPECT_EQ(errno, 8);
EXPECT_EQ(unlink(path), 0);
}
TEST_CASE(test_interp_header_p_filesz_plus_p_offset_overflow_p_memsz)
{
char buffer[0x2000];
auto& header = *(Elf32_Ehdr*)buffer;
header.e_ident[EI_MAG0] = ELFMAG0;
header.e_ident[EI_MAG1] = ELFMAG1;
header.e_ident[EI_MAG2] = ELFMAG2;
header.e_ident[EI_MAG3] = ELFMAG3;
header.e_ident[EI_CLASS] = ELFCLASS32;
header.e_ident[EI_DATA] = ELFDATA2LSB;
header.e_ident[EI_VERSION] = EV_CURRENT;
header.e_ident[EI_OSABI] = ELFOSABI_SYSV;
header.e_ident[EI_ABIVERSION] = 0;
header.e_type = ET_REL;
header.e_version = EV_CURRENT;
header.e_ehsize = sizeof(Elf32_Ehdr);
header.e_machine = EM_386;
header.e_shentsize = sizeof(Elf32_Shdr);
header.e_phoff = 52; // inaccurate
header.e_phentsize = sizeof(Elf32_Phdr); // inaccurate
header.e_shnum = 3; // inaccurate
header.e_shoff = 1024; // inaccurate
header.e_shstrndx = 2; // inaccurate
header.e_entry = 1024; // inaccurate
auto* ph = (Elf32_Phdr*)(&buffer[header.e_phoff]);
ph[0].p_flags = PF_R | PF_X;
ph[0].p_vaddr = 0x00d4;
ph[0].p_align = PAGE_SIZE;
ph[0].p_type = PT_INTERP;
// p_memsz must be of sufficient size to hold maxint - 0x1000
ph[0].p_memsz = 0xfffff000;
// p_offset + p_filesz must not exceed buffer size in order to pass buffer size check in ELF::validate_program_headers().
// p_memsz + p_offset must be sufficiently large to overflow maxint.
ph[0].p_offset = 0x1234;
ph[0].p_filesz = -0x1000;
char path[] = "/tmp/test-elf.XXXXXX";
auto fd = mkstemp(path);
EXPECT_NE(fd, -1);
EXPECT_EQ(fchmod(fd, 0700), 0);
int nwritten = write(fd, buffer, sizeof(buffer));
EXPECT(nwritten);
auto elf_path_or_error = Core::File::read_link(String::formatted("/proc/{}/fd/{}", getpid(), fd));
EXPECT(!elf_path_or_error.is_error());
auto elf_path = elf_path_or_error.release_value();
EXPECT(elf_path.characters());
int rc = execl(elf_path.characters(), "test-elf", nullptr);
EXPECT_EQ(rc, -1);
EXPECT_EQ(errno, 8);
EXPECT_EQ(unlink(path), 0);
}
TEST_CASE(test_load_header_p_memsz_zero)
{
char buffer[0x2000];
auto& header = *(Elf32_Ehdr*)buffer;
header.e_ident[EI_MAG0] = ELFMAG0;
header.e_ident[EI_MAG1] = ELFMAG1;
header.e_ident[EI_MAG2] = ELFMAG2;
header.e_ident[EI_MAG3] = ELFMAG3;
header.e_ident[EI_CLASS] = ELFCLASS32;
header.e_ident[EI_DATA] = ELFDATA2LSB;
header.e_ident[EI_VERSION] = EV_CURRENT;
header.e_ident[EI_OSABI] = ELFOSABI_SYSV;
header.e_ident[EI_ABIVERSION] = 0;
header.e_type = ET_REL;
header.e_version = EV_CURRENT;
header.e_ehsize = sizeof(Elf32_Ehdr);
header.e_machine = EM_386;
header.e_shentsize = sizeof(Elf32_Shdr);
header.e_phoff = 52; // inaccurate
header.e_phentsize = sizeof(Elf32_Phdr); // inaccurate
header.e_shnum = 3; // inaccurate
header.e_shoff = 1024; // inaccurate
header.e_shstrndx = 2; // inaccurate
header.e_entry = 1024; // inaccurate
auto* ph = (Elf32_Phdr*)(&buffer[header.e_phoff]);
ph[0].p_flags = PF_R | PF_X;
ph[0].p_vaddr = 0x00d4;
ph[0].p_align = PAGE_SIZE;
ph[0].p_type = PT_LOAD;
ph[0].p_offset = 0;
ph[0].p_filesz = 0;
// p_memsz zero to trigger crash
ph[0].p_memsz = 0;
char path[] = "/tmp/test-elf.XXXXXX";
auto fd = mkstemp(path);
EXPECT_NE(fd, -1);
EXPECT_EQ(fchmod(fd, 0700), 0);
int nwritten = write(fd, buffer, sizeof(buffer));
EXPECT(nwritten);
auto elf_path_or_error = Core::File::read_link(String::formatted("/proc/{}/fd/{}", getpid(), fd));
EXPECT(!elf_path_or_error.is_error());
auto elf_path = elf_path_or_error.release_value();
EXPECT(elf_path.characters());
int rc = execl(elf_path.characters(), "test-elf", nullptr);
EXPECT_EQ(rc, -1);
EXPECT_EQ(errno, 8);
EXPECT_EQ(unlink(path), 0);
}
TEST_CASE(test_load_header_p_memsz_not_equal_to_p_align)
{
char buffer[0x2000];
auto& header = *(Elf32_Ehdr*)buffer;
header.e_ident[EI_MAG0] = ELFMAG0;
header.e_ident[EI_MAG1] = ELFMAG1;
header.e_ident[EI_MAG2] = ELFMAG2;
header.e_ident[EI_MAG3] = ELFMAG3;
header.e_ident[EI_CLASS] = ELFCLASS32;
header.e_ident[EI_DATA] = ELFDATA2LSB;
header.e_ident[EI_VERSION] = EV_CURRENT;
header.e_ident[EI_OSABI] = ELFOSABI_SYSV;
header.e_ident[EI_ABIVERSION] = 0;
header.e_type = ET_REL;
header.e_version = EV_CURRENT;
header.e_ehsize = sizeof(Elf32_Ehdr);
header.e_machine = EM_386;
header.e_shentsize = sizeof(Elf32_Shdr);
header.e_phoff = 52; // inaccurate
header.e_phentsize = sizeof(Elf32_Phdr); // inaccurate
header.e_shnum = 3; // inaccurate
header.e_shoff = 1024; // inaccurate
header.e_shstrndx = 2; // inaccurate
header.e_entry = 1024; // inaccurate
auto* ph = (Elf32_Phdr*)(&buffer[header.e_phoff]);
ph[0].p_flags = PF_R | PF_X;
ph[0].p_vaddr = 0x00d4;
ph[0].p_type = PT_LOAD;
ph[0].p_memsz = 0xffff0000;
ph[0].p_offset = 0x1000;
ph[0].p_filesz = 0x1000;
// p_align not equal to PAGE_SIZE to trigger crash
ph[0].p_align = PAGE_SIZE / 2;
char path[] = "/tmp/test-elf.XXXXXX";
auto fd = mkstemp(path);
EXPECT_NE(fd, -1);
EXPECT_EQ(fchmod(fd, 0700), 0);
int nwritten = write(fd, buffer, sizeof(buffer));
EXPECT(nwritten);
auto elf_path_or_error = Core::File::read_link(String::formatted("/proc/{}/fd/{}", getpid(), fd));
EXPECT(!elf_path_or_error.is_error());
auto elf_path = elf_path_or_error.release_value();
EXPECT(elf_path.characters());
int rc = execl(elf_path.characters(), "test-elf", nullptr);
EXPECT_EQ(rc, -1);
EXPECT_EQ(errno, 8);
EXPECT_EQ(unlink(path), 0);
}