// https://syzkaller.appspot.com/bug?id=f10ee477162a6f234fa4fc7120fa57a4586533c8 // 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 #include #ifndef __NR_bpf #define __NR_bpf 321 #endif static __thread int clone_ongoing; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) { exit(sig); } uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0; int valid = addr < prog_start || addr > prog_end; if (skip && valid) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { 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(...) \ ({ \ int ok = 1; \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } else \ ok = 0; \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ ok; \ }) 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 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 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 (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[1] = {0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; NONFAILING(*(uint32_t*)0x20000200 = 0x18); NONFAILING(*(uint32_t*)0x20000204 = 4); NONFAILING(*(uint64_t*)0x20000208 = 0x200002c0); NONFAILING(memcpy((void*)0x200002c0, "\x18\x01\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x85\x00\x00\x00\x6d\x00\x00\x00\x95", 25)); NONFAILING(*(uint64_t*)0x20000210 = 0x20000100); NONFAILING(memcpy((void*)0x20000100, "GPL\000", 4)); NONFAILING(*(uint32_t*)0x20000218 = 0); NONFAILING(*(uint32_t*)0x2000021c = 0); NONFAILING(*(uint64_t*)0x20000220 = 0); NONFAILING(*(uint32_t*)0x20000228 = 0); NONFAILING(*(uint32_t*)0x2000022c = 0); NONFAILING(memset((void*)0x20000230, 0, 16)); NONFAILING(*(uint32_t*)0x20000240 = 0); NONFAILING(*(uint32_t*)0x20000244 = 2); NONFAILING(*(uint32_t*)0x20000248 = -1); NONFAILING(*(uint32_t*)0x2000024c = 8); NONFAILING(*(uint64_t*)0x20000250 = 0); NONFAILING(*(uint32_t*)0x20000258 = 0); NONFAILING(*(uint32_t*)0x2000025c = 0x10); NONFAILING(*(uint64_t*)0x20000260 = 0); NONFAILING(*(uint32_t*)0x20000268 = 0); NONFAILING(*(uint32_t*)0x2000026c = 0); NONFAILING(*(uint32_t*)0x20000270 = 0); NONFAILING(*(uint32_t*)0x20000274 = 0); NONFAILING(*(uint64_t*)0x20000278 = 0); NONFAILING(*(uint64_t*)0x20000280 = 0); NONFAILING(*(uint32_t*)0x20000288 = 0x10); NONFAILING(*(uint32_t*)0x2000028c = 0); res = syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x20000200ul, /*size=*/0x80ul); if (res != -1) r[0] = res; NONFAILING(*(uint64_t*)0x20000200 = 0x20000340); NONFAILING(memcpy((void*)0x20000340, "kfree\000", 6)); NONFAILING(*(uint32_t*)0x20000208 = r[0]); syscall(__NR_bpf, /*cmd=*/0x11ul, /*arg=*/0x20000200ul, /*size=*/0x10ul); syscall(__NR_socket, /*domain=*/0x10ul, /*type=*/3ul, /*proto=*/0); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=*/7ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); install_segv_handler(); loop(); return 0; }