// https://syzkaller.appspot.com/bug?id=93aa818833bf716e7e054c7f517329b156377c06 // 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 unsigned long long procid; 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; } #define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off)) #define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len) \ *(type*)(addr) = \ htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) | \ (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len)))) struct csum_inet { uint32_t acc; }; static void csum_inet_init(struct csum_inet* csum) { csum->acc = 0; } static void csum_inet_update(struct csum_inet* csum, const uint8_t* data, size_t length) { if (length == 0) return; size_t i = 0; for (; i < length - 1; i += 2) csum->acc += *(uint16_t*)&data[i]; if (length & 1) csum->acc += le16toh((uint16_t)data[length - 1]); while (csum->acc > 0xffff) csum->acc = (csum->acc & 0xffff) + (csum->acc >> 16); } static uint16_t csum_inet_digest(struct csum_inet* csum) { return ~csum->acc; } 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; memcpy((void*)0x20000000, "/dev/ptmx\000", 10); res = syscall(__NR_openat, 0xffffffffffffff9cul, 0x20000000ul, 0x40001ul, 0ul); if (res != -1) r[0] = res; *(uint16_t*)0x20001180 = 0; *(uint16_t*)0x20001182 = htobe16(0); *(uint8_t*)0x20001184 = 0; *(uint8_t*)0x20001185 = 0; *(uint16_t*)0x20001186 = 0; *(uint16_t*)0x20001188 = 0; *(uint16_t*)0x2000118a = 0; *(uint16_t*)0x2000118c = 0; STORE_BY_BITMASK(uint8_t, , 0x2000118e, 0, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x2000118e, 6, 4, 4); memcpy((void*)0x2000118f, "\x95\x74\xd6", 3); *(uint16_t*)0x20001192 = htobe16(8); *(uint8_t*)0x20001194 = 0x11; *(uint8_t*)0x20001195 = 0; *(uint8_t*)0x20001196 = 0xfe; *(uint8_t*)0x20001197 = 0x88; memset((void*)0x20001198, 0, 12); *(uint8_t*)0x200011a4 = 0; *(uint8_t*)0x200011a5 = 1 + procid * 1; memset((void*)0x200011a6, 0, 16); *(uint16_t*)0x200011b6 = htobe16(0); *(uint16_t*)0x200011b8 = htobe16(0); *(uint16_t*)0x200011ba = htobe16(8); *(uint16_t*)0x200011bc = htobe16(0); struct csum_inet csum_1; csum_inet_init(&csum_1); csum_inet_update(&csum_1, (const uint8_t*)0x20001196, 16); csum_inet_update(&csum_1, (const uint8_t*)0x200011a6, 16); uint32_t csum_1_chunk_2 = 0x8000000; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_2, 4); uint32_t csum_1_chunk_3 = 0x11000000; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_3, 4); csum_inet_update(&csum_1, (const uint8_t*)0x200011b6, 8); *(uint16_t*)0x200011bc = csum_inet_digest(&csum_1); syscall(__NR_write, r[0], 0x20001180ul, 0x3eul); } int main(void) { syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); for (procid = 0; procid < 4; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }