// https://syzkaller.appspot.com/bug?id=d4117099a1b47bdb568410933723fa262993ceb9 // 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 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 long syz_genetlink_get_family_id(long name) { char buf[512] = {0}; struct nlmsghdr* hdr = (struct nlmsghdr*)buf; struct genlmsghdr* genlhdr = (struct genlmsghdr*)NLMSG_DATA(hdr); struct nlattr* attr = (struct nlattr*)(genlhdr + 1); hdr->nlmsg_len = sizeof(*hdr) + sizeof(*genlhdr) + sizeof(*attr) + GENL_NAMSIZ; hdr->nlmsg_type = GENL_ID_CTRL; hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; genlhdr->cmd = CTRL_CMD_GETFAMILY; attr->nla_type = CTRL_ATTR_FAMILY_NAME; attr->nla_len = sizeof(*attr) + GENL_NAMSIZ; NONFAILING(strncpy((char*)(attr + 1), (char*)name, GENL_NAMSIZ)); struct iovec iov = {hdr, hdr->nlmsg_len}; struct sockaddr_nl addr = {0}; addr.nl_family = AF_NETLINK; int fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (fd == -1) { return -1; } struct msghdr msg = {&addr, sizeof(addr), &iov, 1, NULL, 0, 0}; if (sendmsg(fd, &msg, 0) == -1) { close(fd); return -1; } ssize_t n = recv(fd, buf, sizeof(buf), 0); close(fd); if (n <= 0) { return -1; } if (hdr->nlmsg_type != GENL_ID_CTRL) { return -1; } for (; (char*)attr < buf + n; attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) { if (attr->nla_type == CTRL_ATTR_FAMILY_ID) return *(uint16_t*)(attr + 1); } return -1; } #ifndef __NR_sched_setattr #define __NR_sched_setattr 314 #endif int main(void) { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); install_segv_handler(); syscall(__NR_futex, 0, 0x80000000000b, 4, 0, 0, 0); syscall(__NR_perf_event_open, 0, 0, -1, -1, 0); NONFAILING(*(uint32_t*)0x20000440 = 0); NONFAILING(*(uint32_t*)0x20000444 = 6); NONFAILING(*(uint64_t*)0x20000448 = 2); NONFAILING(*(uint32_t*)0x20000450 = 0); NONFAILING(*(uint32_t*)0x20000454 = 0); NONFAILING(*(uint64_t*)0x20000458 = 0x9917); NONFAILING(*(uint64_t*)0x20000460 = 0x1000000000cfbb); NONFAILING(*(uint64_t*)0x20000468 = 0); syscall(__NR_sched_setattr, 0, 0x20000440, 0); syz_genetlink_get_family_id(0); return 0; }