// https://syzkaller.appspot.com/bug?id=b0992a0d6b4b2f691784eac867ee98afe1c88daa // 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 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 uint64_t current_time_ms() { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) fail("clock_gettime failed"); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf)); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } struct ipt_getinfo { char name[32]; unsigned int valid_hooks; unsigned int hook_entry[5]; unsigned int underflow[5]; unsigned int num_entries; unsigned int size; }; struct ipt_get_entries { char name[32]; unsigned int size; void* entrytable[1024 / sizeof(void*)]; }; struct xt_counters { uint64_t pcnt, bcnt; }; struct ipt_replace { char name[32]; unsigned int valid_hooks; unsigned int num_entries; unsigned int size; unsigned int hook_entry[5]; unsigned int underflow[5]; unsigned int num_counters; struct xt_counters* counters; char entrytable[1024]; }; struct ipt_table_desc { const char* name; struct ipt_getinfo info; struct ipt_get_entries entries; struct ipt_replace replace; struct xt_counters counters[10]; }; static struct ipt_table_desc ipv4_tables[] = { {.name = "filter"}, {.name = "nat"}, {.name = "mangle"}, {.name = "raw"}, {.name = "security"}, }; #define IPT_BASE_CTL 64 #define IPT_SO_SET_REPLACE (IPT_BASE_CTL) #define IPT_SO_GET_INFO (IPT_BASE_CTL) #define IPT_SO_GET_ENTRIES (IPT_BASE_CTL + 1) static void checkpoint_net_namespace(void) { socklen_t optlen; unsigned i; int fd; fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (fd == -1) fail("socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)"); for (i = 0; i < sizeof(ipv4_tables) / sizeof(ipv4_tables[0]); i++) { struct ipt_table_desc* table = &ipv4_tables[i]; strcpy(table->info.name, table->name); strcpy(table->entries.name, table->name); strcpy(table->replace.name, table->name); optlen = sizeof(table->info); if (getsockopt(fd, SOL_IP, IPT_SO_GET_INFO, &table->info, &optlen)) { switch (errno) { case EPERM: case ENOENT: case ENOPROTOOPT: continue; } fail("getsockopt(IPT_SO_GET_INFO)"); } if (table->info.size > sizeof(table->entries.entrytable)) fail("table size is too large: %u", table->info.size); if (table->info.num_entries > sizeof(table->counters) / sizeof(table->counters[0])) fail("too many counters: %u", table->info.num_entries); table->entries.size = table->info.size; optlen = sizeof(table->entries) - sizeof(table->entries.entrytable) + table->info.size; if (getsockopt(fd, SOL_IP, IPT_SO_GET_ENTRIES, &table->entries, &optlen)) fail("getsockopt(IPT_SO_GET_ENTRIES)"); table->replace.valid_hooks = table->info.valid_hooks; table->replace.num_entries = table->info.num_entries; table->replace.counters = table->counters; table->replace.size = table->info.size; memcpy(table->replace.hook_entry, table->info.hook_entry, sizeof(table->replace.hook_entry)); memcpy(table->replace.underflow, table->info.underflow, sizeof(table->replace.underflow)); memcpy(table->replace.entrytable, table->entries.entrytable, table->info.size); } close(fd); } static void reset_net_namespace(void) { struct ipt_get_entries entries; struct ipt_getinfo info; socklen_t optlen; unsigned i; int fd; memset(&info, 0, sizeof(info)); memset(&entries, 0, sizeof(entries)); fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (fd == -1) fail("socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)"); for (i = 0; i < sizeof(ipv4_tables) / sizeof(ipv4_tables[0]); i++) { struct ipt_table_desc* table = &ipv4_tables[i]; if (table->info.valid_hooks == 0) continue; strcpy(info.name, table->name); optlen = sizeof(info); if (getsockopt(fd, SOL_IP, IPT_SO_GET_INFO, &info, &optlen)) fail("getsockopt(IPT_SO_GET_INFO)"); if (memcmp(&table->info, &info, sizeof(table->info)) == 0) { strcpy(entries.name, table->name); entries.size = table->info.size; optlen = sizeof(entries) - sizeof(entries.entrytable) + entries.size; if (getsockopt(fd, SOL_IP, IPT_SO_GET_ENTRIES, &entries, &optlen)) fail("getsockopt(IPT_SO_GET_ENTRIES)"); if (memcmp(&table->entries, &entries, optlen) == 0) continue; } table->replace.num_counters = info.num_entries; optlen = sizeof(table->replace) - sizeof(table->replace.entrytable) + table->replace.size; if (setsockopt(fd, SOL_IP, IPT_SO_SET_REPLACE, &table->replace, optlen)) fail("setsockopt(IPT_SO_SET_REPLACE)"); } close(fd); } static void test(); void loop() { int iter; checkpoint_net_namespace(); for (iter = 0;; iter++) { int pid = fork(); if (pid < 0) fail("loop fork failed"); if (pid == 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); test(); doexit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { int res = waitpid(-1, &status, __WALL | WNOHANG); if (res == pid) break; usleep(1000); if (current_time_ms() - start > 5 * 1000) { kill(-pid, SIGKILL); kill(pid, SIGKILL); while (waitpid(-1, &status, __WALL) != pid) { } break; } } reset_net_namespace(); } } #ifndef __NR_mmap #define __NR_mmap 192 #endif #ifndef __NR_epoll_create1 #define __NR_epoll_create1 329 #endif #ifndef __NR_epoll_ctl #define __NR_epoll_ctl 255 #endif #ifndef __NR_ioctl #define __NR_ioctl 54 #endif #undef __NR_mmap #define __NR_mmap __NR_mmap2 long r[2]; void test() { memset(r, -1, sizeof(r)); syscall(__NR_mmap, 0x20000000, 0xfff000, 3, 0x32, -1, 0); r[0] = syscall(__NR_epoll_create1, 0); memcpy((void*)0x20a10000, "/dev/binder#", 13); r[1] = syz_open_dev(0x20a10000, 0, 1); *(uint32_t*)0x20cf7ff4 = 0; *(uint64_t*)0x20cf7ff8 = 0; syscall(__NR_epoll_ctl, r[0], 1, r[1], 0x20cf7ff4); syscall(__NR_ioctl, r[1], 0x40046208, 0); } int main() { for (;;) { loop(); } }