| // general protection fault in loop_validate_file |
| // https://syzkaller.appspot.com/bug?id=7decd880cc0b6176ef23cbd34b9bef40fe159ef7 |
| // status:dup |
| // autogenerated by syzkaller (http://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <linux/futex.h> |
| #include <pthread.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/prctl.h> |
| #include <sys/stat.h> |
| #include <sys/syscall.h> |
| #include <sys/time.h> |
| #include <sys/wait.h> |
| #include <time.h> |
| #include <unistd.h> |
| |
| __attribute__((noreturn)) static void doexit(int status) |
| { |
| volatile unsigned i; |
| syscall(__NR_exit_group, status); |
| for (i = 0;; i++) { |
| } |
| } |
| #include <errno.h> |
| #include <setjmp.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <string.h> |
| |
| const int kFailStatus = 67; |
| const int kRetryStatus = 69; |
| |
| static void fail(const char* msg, ...) |
| { |
| int e = errno; |
| va_list args; |
| va_start(args, msg); |
| vfprintf(stderr, msg, args); |
| va_end(args); |
| fprintf(stderr, " (errno %d)\n", e); |
| doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); |
| } |
| |
| static __thread int skip_segv; |
| static __thread jmp_buf segv_env; |
| |
| static void segv_handler(int sig, siginfo_t* info, void* uctx) |
| { |
| uintptr_t addr = (uintptr_t)info->si_addr; |
| const uintptr_t prog_start = 1 << 20; |
| const uintptr_t prog_end = 100 << 20; |
| if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED) && |
| (addr < prog_start || addr > prog_end)) { |
| _longjmp(segv_env, 1); |
| } |
| doexit(sig); |
| } |
| |
| static void install_segv_handler() |
| { |
| struct sigaction sa; |
| |
| memset(&sa, 0, sizeof(sa)); |
| sa.sa_handler = SIG_IGN; |
| syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); |
| syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); |
| |
| memset(&sa, 0, sizeof(sa)); |
| sa.sa_sigaction = segv_handler; |
| sa.sa_flags = SA_NODEFER | SA_SIGINFO; |
| sigaction(SIGSEGV, &sa, NULL); |
| sigaction(SIGBUS, &sa, NULL); |
| } |
| |
| #define NONFAILING(...) \ |
| { \ |
| __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ |
| if (_setjmp(segv_env) == 0) { \ |
| __VA_ARGS__; \ |
| } \ |
| __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ |
| } |
| |
| static uint64_t current_time_ms() |
| { |
| struct timespec ts; |
| |
| if (clock_gettime(CLOCK_MONOTONIC, &ts)) |
| fail("clock_gettime failed"); |
| return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; |
| } |
| |
| static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t a2) |
| { |
| if (a0 == 0xc || a0 == 0xb) { |
| char buf[128]; |
| sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, |
| (uint8_t)a2); |
| return open(buf, O_RDWR, 0); |
| } else { |
| char buf[1024]; |
| char* hash; |
| NONFAILING(strncpy(buf, (char*)a0, sizeof(buf) - 1)); |
| buf[sizeof(buf) - 1] = 0; |
| while ((hash = strchr(buf, '#'))) { |
| *hash = '0' + (char)(a1 % 10); |
| a1 /= 10; |
| } |
| return open(buf, a2, 0); |
| } |
| } |
| |
| static void execute_one(); |
| extern unsigned long long procid; |
| |
| static void loop() |
| { |
| int iter; |
| for (iter = 0;; iter++) { |
| int pid = fork(); |
| if (pid < 0) |
| fail("clone failed"); |
| if (pid == 0) { |
| prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); |
| setpgrp(); |
| execute_one(); |
| int fd; |
| for (fd = 3; fd < 30; fd++) |
| close(fd); |
| doexit(0); |
| } |
| |
| int status = 0; |
| uint64_t start = current_time_ms(); |
| for (;;) { |
| int res = waitpid(-1, &status, __WALL | WNOHANG); |
| if (res == pid) { |
| break; |
| } |
| usleep(1000); |
| if (current_time_ms() - start < 5 * 1000) |
| continue; |
| kill(-pid, SIGKILL); |
| kill(pid, SIGKILL); |
| while (waitpid(-1, &status, __WALL) != pid) { |
| } |
| break; |
| } |
| } |
| } |
| |
| struct thread_t { |
| int created, running, call; |
| pthread_t th; |
| }; |
| |
| static struct thread_t threads[16]; |
| static void execute_call(int call); |
| static int running; |
| static int collide; |
| |
| static void* thr(void* arg) |
| { |
| struct thread_t* th = (struct thread_t*)arg; |
| for (;;) { |
| while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) |
| syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0); |
| execute_call(th->call); |
| __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); |
| __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE); |
| syscall(SYS_futex, &th->running, FUTEX_WAKE); |
| } |
| return 0; |
| } |
| |
| static void execute(int num_calls) |
| { |
| int call, thread; |
| running = 0; |
| for (call = 0; call < num_calls; call++) { |
| for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]); thread++) { |
| struct thread_t* th = &threads[thread]; |
| if (!th->created) { |
| th->created = 1; |
| pthread_attr_t attr; |
| pthread_attr_init(&attr); |
| pthread_attr_setstacksize(&attr, 128 << 10); |
| pthread_create(&th->th, &attr, thr, th); |
| } |
| if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) { |
| th->call = call; |
| __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); |
| __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE); |
| syscall(SYS_futex, &th->running, FUTEX_WAKE); |
| if (collide && call % 2) |
| break; |
| struct timespec ts; |
| ts.tv_sec = 0; |
| ts.tv_nsec = 20 * 1000 * 1000; |
| syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts); |
| if (__atomic_load_n(&running, __ATOMIC_RELAXED)) |
| usleep((call == num_calls - 1) ? 10000 : 1000); |
| break; |
| } |
| } |
| } |
| } |
| |
| #ifndef __NR_memfd_create |
| #define __NR_memfd_create 319 |
| #endif |
| |
| uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; |
| unsigned long long procid; |
| void execute_call(int call) |
| { |
| long res; |
| switch (call) { |
| case 0: |
| NONFAILING(*(uint32_t*)0x200002c0 = 0xb4); |
| syscall(__NR_getsockopt, -1, 0, 4, 0x20000380, 0x200002c0); |
| break; |
| case 1: |
| NONFAILING(memcpy((void*)0x20000200, "/dev/loop#", 11)); |
| res = syz_open_dev(0x20000200, 0x71, 0x1100082); |
| if (res != -1) |
| r[0] = res; |
| break; |
| case 2: |
| NONFAILING(memcpy( |
| (void*)0x20000080, |
| "\x74\x08\x6e\x75\x00\x00\x00\x00\x00\x00\x00\x00\x00\x8c\x00", 15)); |
| res = syscall(__NR_memfd_create, 0x20000080, 0); |
| if (res != -1) |
| r[1] = res; |
| break; |
| case 3: |
| NONFAILING(*(uint64_t*)0x20000340 = 0x200001c0); |
| NONFAILING(memcpy((void*)0x200001c0, "'", 1)); |
| NONFAILING(*(uint64_t*)0x20000348 = 1); |
| syscall(__NR_pwritev, r[1], 0x20000340, 1, 0x1081806); |
| break; |
| case 4: |
| syscall(__NR_ioctl, r[0], 0x4c00, r[1]); |
| break; |
| case 5: |
| NONFAILING(*(uint64_t*)0x20000240 = 0); |
| syscall(__NR_sendfile, r[0], r[0], 0x20000240, 0x2000005); |
| break; |
| case 6: |
| syscall(__NR_ioctl, r[0], 0x4c01); |
| break; |
| case 7: |
| NONFAILING(memcpy((void*)0x20000140, "/dev/loop#", 11)); |
| res = syz_open_dev(0x20000140, 0, 0x2000); |
| if (res != -1) |
| r[2] = res; |
| break; |
| case 8: |
| syscall(__NR_ioctl, r[2], 0x4c00, r[0]); |
| break; |
| } |
| } |
| |
| void execute_one() |
| { |
| execute(9); |
| collide = 1; |
| execute(9); |
| } |
| |
| int main() |
| { |
| syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); |
| for (procid = 0; procid < 8; procid++) { |
| if (fork() == 0) { |
| install_segv_handler(); |
| for (;;) { |
| loop(); |
| } |
| } |
| } |
| sleep(1000000); |
| return 0; |
| } |