// https://syzkaller.appspot.com/bug?id=4888324093b3dc140652d6af6559586ec828d99a // 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)))) 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 + 1); 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 void setup_fault() { 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) exit(1); } } } 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 < 5 * 1000) continue; kill_and_wait(pid, &status); break; } } } #ifndef __NR_bpf #define __NR_bpf 321 #endif uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; res = syscall(__NR_socket, 0xaul, 1ul, 0); if (res != -1) r[0] = res; *(uint32_t*)0x20000200 = 0x18; *(uint32_t*)0x20000204 = 3; *(uint64_t*)0x20000208 = 0x200000c0; *(uint8_t*)0x200000c0 = 0x18; STORE_BY_BITMASK(uint8_t, , 0x200000c1, 0, 0, 4); STORE_BY_BITMASK(uint8_t, , 0x200000c1, 0, 4, 4); *(uint16_t*)0x200000c2 = 0; *(uint32_t*)0x200000c4 = 0; *(uint8_t*)0x200000c8 = 0; *(uint8_t*)0x200000c9 = 0; *(uint16_t*)0x200000ca = 0; *(uint32_t*)0x200000cc = 0; *(uint8_t*)0x200000d0 = 0x95; *(uint8_t*)0x200000d1 = 0; *(uint16_t*)0x200000d2 = 0; *(uint32_t*)0x200000d4 = 0; *(uint64_t*)0x20000210 = 0x20000080; memcpy((void*)0x20000080, "GPL\000", 4); *(uint32_t*)0x20000218 = 0; *(uint32_t*)0x2000021c = 0; *(uint64_t*)0x20000220 = 0; *(uint32_t*)0x20000228 = 0; *(uint32_t*)0x2000022c = 0; *(uint8_t*)0x20000230 = 0; *(uint8_t*)0x20000231 = 0; *(uint8_t*)0x20000232 = 0; *(uint8_t*)0x20000233 = 0; *(uint8_t*)0x20000234 = 0; *(uint8_t*)0x20000235 = 0; *(uint8_t*)0x20000236 = 0; *(uint8_t*)0x20000237 = 0; *(uint8_t*)0x20000238 = 0; *(uint8_t*)0x20000239 = 0; *(uint8_t*)0x2000023a = 0; *(uint8_t*)0x2000023b = 0; *(uint8_t*)0x2000023c = 0; *(uint8_t*)0x2000023d = 0; *(uint8_t*)0x2000023e = 0; *(uint8_t*)0x2000023f = 0; *(uint32_t*)0x20000240 = 0; *(uint32_t*)0x20000244 = 2; *(uint32_t*)0x20000248 = -1; *(uint32_t*)0x2000024c = 8; *(uint64_t*)0x20000250 = 0; *(uint32_t*)0x20000258 = 0; *(uint32_t*)0x2000025c = 0x10; *(uint64_t*)0x20000260 = 0; *(uint32_t*)0x20000268 = 0; *(uint32_t*)0x2000026c = 0; *(uint32_t*)0x20000270 = 0; res = syscall(__NR_bpf, 5ul, 0x20000200ul, 0x78ul); if (res != -1) r[1] = res; *(uint64_t*)0x200002c0 = 0x20000300; memcpy((void*)0x20000300, "ext4_journal_start\000", 19); *(uint32_t*)0x200002c8 = r[1]; res = syscall(__NR_bpf, 0x11ul, 0x200002c0ul, 0x10ul); if (res != -1) r[2] = res; inject_fault(0); syscall(__NR_dup2, r[0], r[2]); } 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); setup_fault(); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }