// https://syzkaller.appspot.com/bug?id=bea1c185923957c5339d5b43bca13e71047453da // autogenerated by syzkaller (http://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 __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include #include #include #include #include #include const int kFailStatus = 67; const int kRetryStatus = 69; static void fail(const char* msg, ...) { int e = errno; va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); } static void use_temporary_dir() { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) fail("failed to mkdtemp"); if (chmod(tmpdir, 0777)) fail("failed to chmod"); if (chdir(tmpdir)) fail("failed to chdir"); } 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_cgroups() { if (mkdir("/syzcgroup", 0777)) { } if (mkdir("/syzcgroup/unified", 0777)) { } if (mount("none", "/syzcgroup/unified", "cgroup2", 0, NULL)) { } if (chmod("/syzcgroup/unified", 0777)) { } if (!write_file("/syzcgroup/unified/cgroup.subtree_control", "+cpu +memory +io +pids +rdma")) { } if (mkdir("/syzcgroup/cpu", 0777)) { } if (mount("none", "/syzcgroup/cpu", "cgroup", 0, "cpuset,cpuacct,perf_event,hugetlb")) { } if (!write_file("/syzcgroup/cpu/cgroup.clone_children", "1")) { } if (chmod("/syzcgroup/cpu", 0777)) { } if (mkdir("/syzcgroup/net", 0777)) { } if (mount("none", "/syzcgroup/net", "cgroup", 0, "net_cls,net_prio,devices,freezer")) { } if (chmod("/syzcgroup/net", 0777)) { } } static void setup_binfmt_misc() { if (!write_file("/proc/sys/fs/binfmt_misc/register", ":syz0:M:0:syz0::./file0:")) { } if (!write_file("/proc/sys/fs/binfmt_misc/register", ":syz1:M:1:yz1::./file0:POC")) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 8 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); if (unshare(CLONE_NEWNS)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid < 0) fail("sandbox fork failed"); if (pid) return pid; setup_cgroups(); setup_binfmt_misc(); sandbox_common(); if (unshare(CLONE_NEWNET)) { } loop(); doexit(1); } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; unsigned long long procid; void loop() { long res = 0; res = syscall(__NR_socket, 0x26, 5, 0); if (res != -1) r[0] = res; *(uint16_t*)0x20000000 = 0x26; memcpy((void*)0x20000002, "\x68\x61\x73\x68\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 14); *(uint32_t*)0x20000010 = 0; *(uint32_t*)0x20000014 = 0; memcpy((void*)0x20000018, "\x73\x68\x61\x33\x2d\x32\x32\x34\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 64); syscall(__NR_bind, r[0], 0x20000000, 0x58); *(uint32_t*)0x20000080 = 0; res = syscall(__NR_accept4, r[0], 0, 0x20000080, 0); if (res != -1) r[1] = res; *(uint16_t*)0x20000100 = 0x27; *(uint32_t*)0x20000104 = 0; *(uint32_t*)0x20000108 = 1; *(uint32_t*)0x2000010c = 7; *(uint8_t*)0x20000110 = 0; *(uint8_t*)0x20000111 = 0x81; memcpy((void*)0x20000112, "\x35\x93\xce\x3c\x3b\x71\x70\xad\xf0\xa4\xce\x85\xdc\x9a\x75\xc7\x7a" "\x2e\x01\x7e\xca\x04\xc8\x77\xd7\xd7\x9f\x76\x5f\xcf\xc3\xe4\x3a\x5c" "\x8d\x1d\xe5\x9b\x30\x6f\x5b\x57\xf1\xef\x97\xa9\x62\x91\x89\xf3\xdb" "\xe7\x47\xbd\x52\xad\xbe\x4b\xe8\xa0\xde\x13\x81", 63); *(uint64_t*)0x20000158 = 8; syscall(__NR_sendto, r[1], 0x200000c0, 0xfffffffffffffebd, 0, 0x20000100, 0x80); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); use_temporary_dir(); int pid = do_sandbox_none(); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; }