// https://syzkaller.appspot.com/bug?id=08acfb3ecee71b9442e8275dde26607f2ad7c6a1 // 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 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 setup_sysctl() { int cad_pid = fork(); if (cad_pid < 0) exit(1); if (cad_pid == 0) { for (;;) sleep(100); } char tmppid[32]; snprintf(tmppid, sizeof(tmppid), "%d", cad_pid); 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", tmppid}, }; for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].name, files[i].data)) { } } kill(cad_pid, SIGKILL); while (waitpid(cad_pid, NULL, 0) != cad_pid) ; } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; 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); setup_sysctl(); const char* reason; (void)reason; intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // socket$pppl2tp arguments: [ // domain: const = 0x18 (8 bytes) // type: const = 0x1 (8 bytes) // proto: const = 0x1 (4 bytes) // ] // returns sock_pppl2tp res = syscall(__NR_socket, /*domain=*/0x18ul, /*type=*/1ul, /*proto=*/1); if (res != -1) r[0] = res; // socket$inet_udp arguments: [ // domain: const = 0x2 (8 bytes) // type: const = 0x2 (8 bytes) // proto: const = 0x0 (4 bytes) // ] // returns sock_udp res = syscall(__NR_socket, /*domain=*/2ul, /*type=*/2ul, /*proto=*/0); if (res != -1) r[1] = res; // connect$pppl2tp arguments: [ // fd: sock_pppl2tp (resource) // addr: ptr[in, sockaddr_pppl2tp] { // union sockaddr_pppl2tp { // pppol2tpin6: sockaddr_pppl2tp_t[pppol2tpin6_addr] { // sa_family: const = 0x18 (2 bytes) // sa_protocol: const = 0x1 (4 bytes) // addr: pppol2tpin6_addr_t[int16] { // pid: const = 0x0 (4 bytes) // fd: sock (resource) // s_tunnel: int16 = 0x3 (2 bytes) // s_session: int16 = 0x0 (2 bytes) // d_tunnel: int16 = 0x0 (2 bytes) // d_session: int16 = 0x0 (2 bytes) // addr: sockaddr_in6 { // family: const = 0xa (2 bytes) // port: int16be = 0xfffe (2 bytes) // flow: int32be = 0xfffffff8 (4 bytes) // addr: union ipv6_addr { // local: ipv6_addr_t[const[0xaa, int8]] { // a0: const = 0xfe (1 bytes) // a1: const = 0x80 (1 bytes) // a2: buffer: {00 00 00 00 00 00 00 00 00 00 00 00 00} // (length 0xd) a3: const = 0xaa (1 bytes) // } // } // scope: int32 = 0x0 (4 bytes) // } // } // } // } // } // addrlen: len = 0x32 (8 bytes) // ] *(uint16_t*)0x200000000980 = 0x18; *(uint32_t*)0x200000000982 = 1; *(uint32_t*)0x200000000986 = 0; *(uint32_t*)0x20000000098a = r[1]; *(uint16_t*)0x20000000098e = 3; *(uint16_t*)0x200000000990 = 0; *(uint16_t*)0x200000000992 = 0; *(uint16_t*)0x200000000994 = 0; *(uint16_t*)0x200000000996 = 0xa; *(uint16_t*)0x200000000998 = htobe16(0xfffe); *(uint32_t*)0x20000000099a = htobe32(0xfffffff8); *(uint8_t*)0x20000000099e = 0xfe; *(uint8_t*)0x20000000099f = 0x80; memset((void*)0x2000000009a0, 0, 13); *(uint8_t*)0x2000000009ad = 0xaa; *(uint32_t*)0x2000000009ae = 0; syscall(__NR_connect, /*fd=*/r[0], /*addr=*/0x200000000980ul, /*addrlen=*/0x32ul); // ioctl$ifreq_SIOCGIFINDEX_batadv_hard arguments: [ // fd: sock (resource) // cmd: const = 0x8933 (4 bytes) // arg: nil // ] syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x8933, /*arg=*/0ul); return 0; }