// https://syzkaller.appspot.com/bug?id=1c7edd2967e60778f50a15dc59f5cf851ab8de54 // 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 #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; } static void use_temporary_dir(void) { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) exit(1); if (chmod(tmpdir, 0777)) exit(1); if (chdir(tmpdir)) exit(1); } 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; } #define MAX_FDS 30 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)) { } 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")) { } 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_cgroups_loop() { int pid = getpid(); char file[128]; char cgroupdir[64]; snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/pids.max", cgroupdir); write_file(file, "32"); snprintf(file, sizeof(file), "%s/memory.low", cgroupdir); write_file(file, "%d", 298 << 20); snprintf(file, sizeof(file), "%s/memory.high", cgroupdir); write_file(file, "%d", 299 << 20); snprintf(file, sizeof(file), "%s/memory.max", cgroupdir); write_file(file, "%d", 300 << 20); snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); } static void setup_cgroups_test() { char cgroupdir[64]; snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); if (symlink(cgroupdir, "./cgroup")) { } snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); if (symlink(cgroupdir, "./cgroup.cpu")) { } snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); if (symlink(cgroupdir, "./cgroup.net")) { } } static void setup_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } setup_cgroups(); } 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 = (200 << 20); setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 136 << 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); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } typedef struct { const char* name; const char* value; } sysctl_t; static const sysctl_t sysctls[] = { {"/proc/sys/kernel/shmmax", "16777216"}, {"/proc/sys/kernel/shmall", "536870912"}, {"/proc/sys/kernel/shmmni", "1024"}, {"/proc/sys/kernel/msgmax", "8192"}, {"/proc/sys/kernel/msgmni", "1024"}, {"/proc/sys/kernel/msgmnb", "1024"}, {"/proc/sys/kernel/sem", "1024 1048576 500 1024"}, }; unsigned i; for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++) write_file(sysctls[i].name, sysctls[i].value); } static int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static void drop_caps(void) { struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1); const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE); cap_data[0].effective &= ~drop; cap_data[0].permitted &= ~drop; cap_data[0].inheritable &= ~drop; if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1); } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid != 0) return wait_for_loop(pid); setup_common(); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } loop(); exit(1); } #define FS_IOC_SETFLAGS _IOW('f', 2, long) static void remove_dir(const char* dir) { DIR* dp; struct dirent* ep; int iter = 0; retry: dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exit(1); } exit(1); } while ((ep = readdir(dp))) { if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue; char filename[FILENAME_MAX]; snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); struct stat st; if (lstat(filename, &st)) exit(1); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } int i; for (i = 0;; i++) { if (unlink(filename) == 0) break; if (errno == EPERM) { int fd = open(filename, O_RDONLY); if (fd != -1) { long flags = 0; if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) { } close(fd); continue; } } if (errno == EROFS) { break; } if (errno != EBUSY || i > 100) exit(1); } } closedir(dp); int i; for (i = 0;; i++) { if (rmdir(dir) == 0) break; if (i < 100) { if (errno == EPERM) { int fd = open(dir, O_RDONLY); if (fd != -1) { long flags = 0; if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) { } close(fd); continue; } } if (errno == EROFS) { break; } if (errno == EBUSY) { continue; } if (errno == ENOTEMPTY) { if (iter < 100) { iter++; goto retry; } } } exit(1); } } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); int i; for (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_loop() { setup_cgroups_loop(); } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setup_cgroups_test(); write_file("/proc/self/oom_score_adj", "1000"); } static void close_fds() { int fd; for (fd = 3; fd < MAX_FDS; fd++) close(fd); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { setup_loop(); int iter; for (iter = 0;; iter++) { char cwdbuf[32]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) exit(1); int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { if (chdir(cwdbuf)) exit(1); setup_test(); execute_one(); close_fds(); 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; } remove_dir(cwdbuf); } } uint64_t r[1] = {0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; memcpy((void*)0x20000080, "/dev/uhid\000", 10); res = syscall(__NR_openat, 0xffffffffffffff9cul, 0x20000080ul, 2ul, 0ul); if (res != -1) r[0] = res; memcpy( (void*)0x20000b40, "\x0b\x00\x00\x00\x73\x79\x7a\x31\x03\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\x06\x00\x00\x8a\x8e\x87\x4b\x73\xe9\x90\xb4" "\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\x2b" "\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x01\x00\x73\x8d\x7a\x31\x00\x00\x00\x00\x00\xff\x07\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\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\x73\x79" "\x7a\x31\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\xcf\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x0c\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\x16\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x3b\x38\xe9\x67\xac\x82\x06\xea" "\xae\x86\xb9\x7e\xec\x0b\x2b\xed\x1e\xe2\x33\x64\xb1\x0d\x6a\xad\x51\x02" "\x00\x00\x00\xe2\xa5\xdb\x3c\x6a\x0d\xee\x4a\xfc\x66\xd2\x44\x28\x05\x20" "\x1c\x39\x38\x9a\x80\x4c\x41\xc2\x99\x3f\xc6\x7e\x8a\x14\x60\x45\xe1\x4a" "\x8a\x08\x00\x55\x0e\x6a\x25\xc0\xef\x65\xf6\x00\x00\x00\x00\x00\x00\x00" "\x03\x18\x7f\xaf\xa4\xa1\xee\x6e\xce\x53\xc6\x73\x85\xb8\x83\xa3\x6a\xd2" "\x4a\x04\x00\x00\x00\x00\x00\x00\x00\x6a\x8a\xb1\x1b\x0a\x0b\x00\xe7\x7e" "\x6c\x16\x18\x9c\xd3\x16\xcb\xe0\x1a\x4c\xe4\x11\x37\x8e\xaa\xb7\x37\x2d" "\xab\x5e\xef\x84\xc3\x1b\x2d\xad\x86\x8a\x53\xe6\xf5\xe6\x97\x46\xa7\x1e" "\xc9\x2d\xca\xa9\xa7\xdf\xab\x39\x42\x86\xe5\xc8\x1e\xae\x45\xe3\x00\x00" "\x94\x2b\x8d\xa1\x1e\xdb\x57\x8b\x45\x3a\xca\xc0\x3a\x9d\x34\x48\x00\x00" "\x00\x00\x83\xd6\xd5\xfe\x4f\x83\x3d\x4d\x4c\xfb\xee\xf0\xe0\xe6\x2b\xe2" "\x05\x00\x00\x00\x3c\x32\x98\x4c\x6c\x4b\x2b\x9c\x33\xd8\xa6\x24\xce\xa9" "\x5c\x3b\x3c\x6d\xd8\x73\x56\x9c\xf4\x78\x6f\xc5\x16\x6b\x03\x00\x00\x00" "\x00\x00\x1f\xf2\x8d\x3c\xe3\xe3\xb8\xf8\x1e\x34\xcf\x97\xc9\xc8\x41\xcb" "\x2e\xf0\x81\x07\xa9\xa9\x65\x49\xe3\xd2\x59\xdf\x17\xe2\x9e\xd6\x4b\xd6" "\x12\x08\x13\xf9\xf0\x34\x4e\x13\x95\x06\x70\x1e\x8f\xde\xdb\x06\x00\x9b" "\x5e\x4d\x0c\x67\xbd\xa0\xb9\x28\xb7\x32\xcf\xf7\x82\xb0\x68\x40\x75\xf2" "\xcb\x78\x51\xef\xdd\x77\x97\xee\x95\xd2\xac\x28\xa8\xca\xbd\x26\xc1\x56" "\x82\xaa\x78\xd3\x1a\xec\x95\x6b\xd7\xc2\x78\x06\x40\x34\x34\xb3\xc3\x0b" "\x07\x0b\xcc\x82\x66\xe1\x2f\xa6\x66\x02\x05\x62\x56\xf7\x46\x75\xb7\xcb" "\x4d\x87\xb2\x70\x8d\x70\xc8\xca\xf8\xfe\x18\x0c\x4d\xea\x3f\x5b\x7a\x87" "\x1b\x30\xc7\xa5\x75\x3b\x48\xf7\xf0\x91\x92\xa3\x4b\x0e\xfa\xab\x02\xdc" "\xa0\x51\x7e\xee\x50\xff\x30\x20\x6f\x78\xec\x82\xc7\x2f\x33\xe9\x09\xc1" "\xae\x1f\xe9\x4f\xe0\x75\x9f\x07\xd1\x64\x02\x59\x3e\x33\x35\xd4\x20\x00" "\x88\x8c\x90\x5f\xb4\x1d\xbd\xb4\x20\xea\x9f\x87\xfc\x86\x51\x26\x85\xeb" "\x72\x61\xe9\xc2\x5e\xdb\x60\x95\xe9\xec\x2b\x74\x3b\xcf\x0f\x46\x8b\xad" "\xa0\xb8\x7a\x02\x60\x65\x30\xc2\x78\xa4\xc6\x00\x00\x00", 770); syscall(__NR_write, r[0], 0x20000b40ul, 0x12eul); *(uint32_t*)0x20000040 = 0xc; *(uint16_t*)0x20000044 = 0x29; memcpy((void*)0x20000046, "\xe6\x31\x18\x91\x99\x84\x9b\x25\x72\xac\x03\xb2" "\x2a\x73\x63\xff\x09\x3e\xf1\xd3\x9f\xf4\x06\xe2" "\x57\x94\x86\x93\x7f\x39\xd1\x45\xf7\x8d\x80\xc3" "\xce\x6f\x84\x2d\x3f", 41); syscall(__NR_write, r[0], 0x20000040ul, 0x2ful); } int main(void) { syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { use_temporary_dir(); do_sandbox_none(); } } sleep(1000000); return 0; }