// https://syzkaller.appspot.com/bug?id=e327d2e5716f7256cc21790eba2e6a96e4821810 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } static int inject_fault(int nth) { int fd; fd = open("/proc/thread-self/fail-nth", O_RDWR); if (fd == -1) exit(1); char buf[16]; sprintf(buf, "%d", nth); if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) exit(1); return fd; } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); } static const char* setup_fault() { int fd = open("/proc/self/make-it-fail", O_WRONLY); if (fd == -1) return "CONFIG_FAULT_INJECTION is not enabled"; close(fd); fd = open("/proc/thread-self/fail-nth", O_WRONLY); if (fd == -1) return "kernel does not have systematic fault injection support"; close(fd); static struct { const char* file; const char* val; bool fatal; } files[] = { {"/sys/kernel/debug/failslab/ignore-gfp-wait", "N", true}, {"/sys/kernel/debug/fail_futex/ignore-private", "N", false}, {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem", "N", false}, {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait", "N", false}, {"/sys/kernel/debug/fail_page_alloc/min-order", "0", false}, }; unsigned i; for (i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].file, files[i].val)) { if (files[i].fatal) return "failed to write fault injection file"; } } return NULL; } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter = 0; for (;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { sleep_ms(10); if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } memcpy((void*)0x200000000280, "./file0\000", 8); syscall(__NR_creat, /*file=*/0x200000000280ul, /*mode=S_IROTH|S_IXGRP|S_IXUSR|S_IWUSR|S_IRUSR|0xecf86c37d5304800*/ 0xecf86c37d53049ccul); res = syscall(__NR_pipe2, /*pipefd=*/0x200000001900ul, /*flags=*/0ul); if (res != -1) { r[0] = *(uint32_t*)0x200000001900; r[1] = *(uint32_t*)0x200000001904; } memcpy((void*)0x200000000500, "\x15\x00\x00\x00\x65\xff\xff\x04\x80\x00\x00\x08\x00\x39\x50\x32\x30" "\x30\x30", 19); syscall(__NR_write, /*fd=*/r[1], /*data=*/0x200000000500ul, /*size=*/0x15ul); res = syscall(__NR_dup, /*oldfd=*/r[1]); if (res != -1) r[2] = res; *(uint32_t*)0x200000000100 = 0x18; *(uint32_t*)0x200000000104 = 0; *(uint64_t*)0x200000000108 = 0; *(uint64_t*)0x200000000110 = 0; syscall(__NR_write, /*fd=*/r[2], /*arg=*/0x200000000100ul, /*len=*/0x18ul); *(uint32_t*)0x2000000000c0 = 0x14c; *(uint32_t*)0x2000000000c4 = 5; *(uint64_t*)0x2000000000c8 = 0; *(uint64_t*)0x2000000000d0 = 0; *(uint64_t*)0x2000000000d8 = 0; *(uint64_t*)0x2000000000e0 = 0; *(uint32_t*)0x2000000000e8 = 0; *(uint32_t*)0x2000000000ec = 0; syscall(__NR_write, /*fd=*/r[2], /*arg=*/0x2000000000c0ul, /*len=*/0x137ul); memcpy((void*)0x200000000000, "./file0\000", 8); memcpy((void*)0x200000000040, "9p\000", 3); memcpy((void*)0x200000000540, "trans=fd,", 9); memcpy((void*)0x200000000549, "rfdno", 5); *(uint8_t*)0x20000000054e = 0x3d; sprintf((char*)0x20000000054f, "0x%016llx", (long long)r[0]); *(uint8_t*)0x200000000561 = 0x2c; memcpy((void*)0x200000000562, "wfdno", 5); *(uint8_t*)0x200000000567 = 0x3d; sprintf((char*)0x200000000568, "0x%016llx", (long long)r[2]); *(uint8_t*)0x20000000057a = 0x2c; *(uint8_t*)0x20000000057b = 0x6b; syscall(__NR_mount, /*src=*/0ul, /*dst=*/0x200000000000ul, /*type=*/0x200000000040ul, /*flags=*/0ul, /*opts=*/0x200000000540ul); memcpy((void*)0x200000000240, "./file0\000", 8); syscall(__NR_truncate, /*file=*/0x200000000240ul, /*len=*/0x206b12ul); memcpy((void*)0x2000000002c0, "./file0\000", 8); res = syscall(__NR_creat, /*file=*/0x2000000002c0ul, /*mode=S_IWOTH|S_IROTH*/ 6ul); if (res != -1) r[3] = res; inject_fault(10); syscall(__NR_write, /*fd=*/r[3], /*buf=*/0x200000000380ul, /*count=*/0x36ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; if ((reason = setup_fault())) printf("the reproducer may not work as expected: fault injection setup " "failed: %s\n", reason); loop(); return 0; }