// https://syzkaller.appspot.com/bug?id=fecd3274ae6917477cfd0a33b12e1f56da6223b6 // 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 unsigned long long procid; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED) && (addr < prog_start || addr > prog_end)) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_IGN; syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = segv_handler; sa.sa_flags = SA_NODEFER | SA_SIGINFO; sigaction(SIGSEGV, &sa, NULL); sigaction(SIGBUS, &sa, NULL); } #define NONFAILING(...) \ { \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ } 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 setup_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } } 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 = 160 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 8 << 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)) { } } int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } 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(); if (unshare(CLONE_NEWNET)) { } loop(); 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) { } } #define SYZ_HAVE_SETUP_TEST 1 static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); } #define SYZ_HAVE_RESET_TEST 1 static void reset_test() { int fd; for (fd = 3; fd < 30; fd++) close(fd); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter; for (iter = 0;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); reset_test(); 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_fcntl #define __NR_fcntl 55 #endif #ifndef __NR_inotify_init1 #define __NR_inotify_init1 332 #endif #ifndef __NR_mmap #define __NR_mmap 192 #endif #ifndef __NR_sendmmsg #define __NR_sendmmsg 345 #endif #ifndef __NR_sendmsg #define __NR_sendmsg 370 #endif #ifndef __NR_socket #define __NR_socket 359 #endif #ifndef __NR_tkill #define __NR_tkill 238 #endif #undef __NR_mmap #define __NR_mmap __NR_mmap2 uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0x0}; void execute_one(void) { long res = 0; res = syscall(__NR_socket, 0xf, 3, 2); if (res != -1) r[0] = res; NONFAILING(*(uint32_t*)0x20000180 = 0); NONFAILING(*(uint32_t*)0x20000184 = 0); NONFAILING(*(uint32_t*)0x20000188 = 0x20000040); NONFAILING(*(uint32_t*)0x20000040 = 0x20000100); NONFAILING(*(uint32_t*)0x20000044 = 0); NONFAILING(*(uint32_t*)0x2000018c = 1); NONFAILING(*(uint32_t*)0x20000190 = 0); NONFAILING(*(uint32_t*)0x20000194 = 0); NONFAILING(*(uint32_t*)0x20000198 = 0); syscall(__NR_sendmsg, -1, 0x20000180, 0); NONFAILING(*(uint32_t*)0x20000000 = 0x40000000); NONFAILING(*(uint32_t*)0x20000004 = 0); NONFAILING(*(uint32_t*)0x20000008 = 0x20000040); NONFAILING(*(uint32_t*)0x20000040 = 0x20000080); NONFAILING( memcpy((void*)0x20000080, "\x02\x03\x00\x09\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x02\x00\x13\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01" "\x05\x00\x06\x00\x20\x00\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\xe5\x00\x00\x00\x00\x00\x00\x1f\x00\x00\x00\x00\x00" "\x00\x03\x00\x00\x00\x00\x00\x00\x02\x00\x01\x00\x00\x00\x00\x00" "\x00\x00\x00\x02\x00\x00\x00\x00\x05\x00\x05\x00\x00\x00\x00\x00" "\x0a\x00\x00\x00\x00\x00\x00\x00\xff\x17\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x17\x00\x00\x00\x00\x00\x00\x00\x00", 128)); NONFAILING(*(uint32_t*)0x20000044 = 0x80); NONFAILING(*(uint32_t*)0x2000000c = 1); NONFAILING(*(uint32_t*)0x20000010 = 0); NONFAILING(*(uint32_t*)0x20000014 = 0); NONFAILING(*(uint32_t*)0x20000018 = 0); syscall(__NR_sendmsg, -1, 0x20000000, 0); syscall(__NR_sendmmsg, (long)r[0], 0x20000180, 0x117, 0); res = syscall(__NR_inotify_init1, 0); if (res != -1) r[1] = res; syscall(__NR_fcntl, (long)r[1], 8, -1); res = syscall(__NR_fcntl, (long)r[1], 0x10, 0x20000040); if (res != -1) NONFAILING(r[2] = *(uint32_t*)0x20000044); syscall(__NR_tkill, (long)r[2], 7); } int main(void) { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); install_segv_handler(); for (procid = 0; procid < 8; procid++) { if (fork() == 0) { do_sandbox_none(); } } sleep(1000000); return 0; }