// https://syzkaller.appspot.com/bug?id=7cd9e7df4b52f9561f1dbb73c449f52b2a7ab310 // 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 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_sysctl() { char mypid[32]; snprintf(mypid, sizeof(mypid), "%d", getpid()); struct { const char* name; const char* data; } files[] = { {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"}, {"/proc/sys/kernel/hung_task_check_interval_secs", "20"}, {"/proc/sys/net/core/bpf_jit_kallsyms", "1"}, {"/proc/sys/net/core/bpf_jit_harden", "0"}, {"/proc/sys/kernel/kptr_restrict", "0"}, {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"}, {"/proc/sys/fs/mount-max", "100"}, {"/proc/sys/vm/oom_dump_tasks", "0"}, {"/proc/sys/debug/exception-trace", "0"}, {"/proc/sys/kernel/printk", "7 4 1 3"}, {"/proc/sys/kernel/keys/gc_delay", "1"}, {"/proc/sys/vm/oom_kill_allocating_task", "1"}, {"/proc/sys/kernel/ctrl-alt-del", "0"}, {"/proc/sys/kernel/cad_pid", mypid}, }; for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].name, files[i].data)) printf("write to %s failed: %s\n", files[i].name, strerror(errno)); } } 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[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; res = syscall(__NR_socket, 0x10ul, 3ul, 0xc); if (res != -1) r[0] = res; *(uint64_t*)0x20000200 = 0; *(uint32_t*)0x20000208 = 0; *(uint64_t*)0x20000210 = 0x20000140; *(uint64_t*)0x20000140 = 0x20000440; memcpy( (void*)0x20000440, "\x5c\x00\x00\x00\x02\x06\x01\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x05\x00\x05\x00\x02\x00\x00\x00\x05\x00\x04\x00\x00\x00\x00\x00" "\x05\x00\x01\x00\x07\x00\x00\x00\x09\x00\x02\x00\x73\x79\x7a\x30\x00\x00" "\x00\x00\x0d\x00\x03\x00\x68\x61\x73\x68\x3a\x6e\x65\x74\x00\x00\x00\x00" "\x14\x00\x07\x80\x05\x00\x15\x00\x07\x00\x00\x00\x08\x00\x11", 87); *(uint64_t*)0x20000148 = 0x5c; *(uint64_t*)0x20000218 = 1; *(uint64_t*)0x20000220 = 0; *(uint64_t*)0x20000228 = 0; *(uint32_t*)0x20000230 = 0; syscall(__NR_sendmsg, r[0], 0x20000200ul, 0ul); res = syscall(__NR_socket, 0x10ul, 3ul, 0xc); if (res != -1) r[1] = res; *(uint64_t*)0x20000000 = 0; *(uint32_t*)0x20000008 = 0; *(uint64_t*)0x20000010 = 0x20000280; *(uint64_t*)0x20000280 = 0x200000c0; *(uint32_t*)0x200000c0 = 0x44; *(uint8_t*)0x200000c4 = 9; *(uint8_t*)0x200000c5 = 6; *(uint16_t*)0x200000c6 = 0x401; *(uint32_t*)0x200000c8 = 0; *(uint32_t*)0x200000cc = 5; *(uint8_t*)0x200000d0 = 0; *(uint8_t*)0x200000d1 = 0; *(uint16_t*)0x200000d2 = htobe16(0); *(uint16_t*)0x200000d4 = 9; *(uint16_t*)0x200000d6 = 2; memcpy((void*)0x200000d8, "syz0\000", 5); *(uint16_t*)0x200000e0 = 0x1c; STORE_BY_BITMASK(uint16_t, , 0x200000e2, 7, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x200000e3, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x200000e3, 1, 7, 1); *(uint16_t*)0x200000e4 = 0xc; STORE_BY_BITMASK(uint16_t, , 0x200000e6, 1, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x200000e7, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x200000e7, 1, 7, 1); *(uint16_t*)0x200000e8 = 8; STORE_BY_BITMASK(uint16_t, , 0x200000ea, 1, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x200000eb, 1, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x200000eb, 0, 7, 1); *(uint8_t*)0x200000ec = 0xac; *(uint8_t*)0x200000ed = 0x14; *(uint8_t*)0x200000ee = 0x14; *(uint8_t*)0x200000ef = 0; *(uint16_t*)0x200000f0 = 0xc; STORE_BY_BITMASK(uint16_t, , 0x200000f2, 2, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x200000f3, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x200000f3, 1, 7, 1); *(uint16_t*)0x200000f4 = 8; STORE_BY_BITMASK(uint16_t, , 0x200000f6, 1, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x200000f7, 1, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x200000f7, 0, 7, 1); *(uint32_t*)0x200000f8 = htobe32(0xa010100); *(uint16_t*)0x200000fc = 5; *(uint16_t*)0x200000fe = 1; *(uint8_t*)0x20000100 = 7; *(uint64_t*)0x20000288 = 0x44; *(uint64_t*)0x20000018 = 1; *(uint64_t*)0x20000020 = 0; *(uint64_t*)0x20000028 = 0; *(uint32_t*)0x20000030 = 4; syscall(__NR_sendmsg, r[1], 0x20000000ul, 0ul); } 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_sysctl(); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }