18a272653SPeter Holm#!/bin/sh 28a272653SPeter Holm 38a272653SPeter Holm# panic: mtx_lock() of spin mutex (null) @ ../../../netinet/tcp_output.c:350 48a272653SPeter Holm# cpuid = 1 58a272653SPeter Holm# time = 1587276361 68a272653SPeter Holm# KDB: stack backtrace: 78a272653SPeter Holm# db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe01388956f0 88a272653SPeter Holm# vpanic() at vpanic+0x182/frame 0xfffffe0138895740 98a272653SPeter Holm# panic() at panic+0x43/frame 0xfffffe01388957a0 108a272653SPeter Holm# __mtx_lock_flags() at __mtx_lock_flags+0x13c/frame 0xfffffe01388957f0 118a272653SPeter Holm# tcp_output() at tcp_output+0x34e/frame 0xfffffe0138895980 128a272653SPeter Holm# tcp_usr_connect() at tcp_usr_connect+0x123/frame 0xfffffe01388959e0 138a272653SPeter Holm# soconnectat() at soconnectat+0xd0/frame 0xfffffe0138895a30 148a272653SPeter Holm# kern_connectat() at kern_connectat+0xe2/frame 0xfffffe0138895a90 158a272653SPeter Holm# sys_connect() at sys_connect+0x75/frame 0xfffffe0138895ad0 168a272653SPeter Holm# amd64_syscall() at amd64_syscall+0x159/frame 0xfffffe0138895bf0 178a272653SPeter Holm# fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe0138895bf0 188a272653SPeter Holm 198a272653SPeter Holm# Reproduced on r358885 208a272653SPeter Holm 218a272653SPeter Holm[ `uname -p` = "i386" ] && exit 0 228a272653SPeter Holm 238a272653SPeter Holm. ../default.cfg 248a272653SPeter Holmcat > /tmp/syzkaller11.c <<EOF 258a272653SPeter Holm// https://syzkaller.appspot.com/bug?id=f81a41d30e772445b13de6dcf07fc1afaf122a61 268a272653SPeter Holm// autogenerated by syzkaller (https://github.com/google/syzkaller) 278a272653SPeter Holm 288a272653SPeter Holm#define _GNU_SOURCE 298a272653SPeter Holm 308a272653SPeter Holm#include <sys/types.h> 318a272653SPeter Holm 328a272653SPeter Holm#include <errno.h> 338a272653SPeter Holm#include <pthread.h> 348a272653SPeter Holm#include <pwd.h> 358a272653SPeter Holm#include <signal.h> 368a272653SPeter Holm#include <stdarg.h> 378a272653SPeter Holm#include <stdbool.h> 388a272653SPeter Holm#include <stdint.h> 398a272653SPeter Holm#include <stdio.h> 408a272653SPeter Holm#include <stdlib.h> 418a272653SPeter Holm#include <string.h> 428a272653SPeter Holm#include <sys/endian.h> 438a272653SPeter Holm#include <sys/syscall.h> 448a272653SPeter Holm#include <sys/wait.h> 458a272653SPeter Holm#include <time.h> 468a272653SPeter Holm#include <unistd.h> 478a272653SPeter Holm 488a272653SPeter Holmstatic void kill_and_wait(int pid, int* status) 498a272653SPeter Holm{ 508a272653SPeter Holm kill(pid, SIGKILL); 518a272653SPeter Holm while (waitpid(-1, status, 0) != pid) { 528a272653SPeter Holm } 538a272653SPeter Holm} 548a272653SPeter Holm 558a272653SPeter Holmstatic void sleep_ms(uint64_t ms) 568a272653SPeter Holm{ 578a272653SPeter Holm usleep(ms * 1000); 588a272653SPeter Holm} 598a272653SPeter Holm 608a272653SPeter Holmstatic uint64_t current_time_ms(void) 618a272653SPeter Holm{ 628a272653SPeter Holm struct timespec ts; 638a272653SPeter Holm if (clock_gettime(CLOCK_MONOTONIC, &ts)) 648a272653SPeter Holm exit(1); 658a272653SPeter Holm return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; 668a272653SPeter Holm} 678a272653SPeter Holm 688a272653SPeter Holmstatic void thread_start(void* (*fn)(void*), void* arg) 698a272653SPeter Holm{ 708a272653SPeter Holm pthread_t th; 718a272653SPeter Holm pthread_attr_t attr; 728a272653SPeter Holm pthread_attr_init(&attr); 738a272653SPeter Holm pthread_attr_setstacksize(&attr, 128 << 10); 748a272653SPeter Holm int i; 758a272653SPeter Holm for (i = 0; i < 100; i++) { 768a272653SPeter Holm if (pthread_create(&th, &attr, fn, arg) == 0) { 778a272653SPeter Holm pthread_attr_destroy(&attr); 788a272653SPeter Holm return; 798a272653SPeter Holm } 808a272653SPeter Holm if (errno == EAGAIN) { 818a272653SPeter Holm usleep(50); 828a272653SPeter Holm continue; 838a272653SPeter Holm } 848a272653SPeter Holm break; 858a272653SPeter Holm } 868a272653SPeter Holm exit(1); 878a272653SPeter Holm} 888a272653SPeter Holm 898a272653SPeter Holmtypedef struct { 908a272653SPeter Holm pthread_mutex_t mu; 918a272653SPeter Holm pthread_cond_t cv; 928a272653SPeter Holm int state; 938a272653SPeter Holm} event_t; 948a272653SPeter Holm 958a272653SPeter Holmstatic void event_init(event_t* ev) 968a272653SPeter Holm{ 978a272653SPeter Holm if (pthread_mutex_init(&ev->mu, 0)) 988a272653SPeter Holm exit(1); 998a272653SPeter Holm if (pthread_cond_init(&ev->cv, 0)) 1008a272653SPeter Holm exit(1); 1018a272653SPeter Holm ev->state = 0; 1028a272653SPeter Holm} 1038a272653SPeter Holm 1048a272653SPeter Holmstatic void event_reset(event_t* ev) 1058a272653SPeter Holm{ 1068a272653SPeter Holm ev->state = 0; 1078a272653SPeter Holm} 1088a272653SPeter Holm 1098a272653SPeter Holmstatic void event_set(event_t* ev) 1108a272653SPeter Holm{ 1118a272653SPeter Holm pthread_mutex_lock(&ev->mu); 1128a272653SPeter Holm if (ev->state) 1138a272653SPeter Holm exit(1); 1148a272653SPeter Holm ev->state = 1; 1158a272653SPeter Holm pthread_mutex_unlock(&ev->mu); 1168a272653SPeter Holm pthread_cond_broadcast(&ev->cv); 1178a272653SPeter Holm} 1188a272653SPeter Holm 1198a272653SPeter Holmstatic void event_wait(event_t* ev) 1208a272653SPeter Holm{ 1218a272653SPeter Holm pthread_mutex_lock(&ev->mu); 1228a272653SPeter Holm while (!ev->state) 1238a272653SPeter Holm pthread_cond_wait(&ev->cv, &ev->mu); 1248a272653SPeter Holm pthread_mutex_unlock(&ev->mu); 1258a272653SPeter Holm} 1268a272653SPeter Holm 1278a272653SPeter Holmstatic int event_isset(event_t* ev) 1288a272653SPeter Holm{ 1298a272653SPeter Holm pthread_mutex_lock(&ev->mu); 1308a272653SPeter Holm int res = ev->state; 1318a272653SPeter Holm pthread_mutex_unlock(&ev->mu); 1328a272653SPeter Holm return res; 1338a272653SPeter Holm} 1348a272653SPeter Holm 1358a272653SPeter Holmstatic int event_timedwait(event_t* ev, uint64_t timeout) 1368a272653SPeter Holm{ 1378a272653SPeter Holm uint64_t start = current_time_ms(); 1388a272653SPeter Holm uint64_t now = start; 1398a272653SPeter Holm pthread_mutex_lock(&ev->mu); 1408a272653SPeter Holm for (;;) { 1418a272653SPeter Holm if (ev->state) 1428a272653SPeter Holm break; 1438a272653SPeter Holm uint64_t remain = timeout - (now - start); 1448a272653SPeter Holm struct timespec ts; 1458a272653SPeter Holm ts.tv_sec = remain / 1000; 1468a272653SPeter Holm ts.tv_nsec = (remain % 1000) * 1000 * 1000; 1478a272653SPeter Holm pthread_cond_timedwait(&ev->cv, &ev->mu, &ts); 1488a272653SPeter Holm now = current_time_ms(); 1498a272653SPeter Holm if (now - start > timeout) 1508a272653SPeter Holm break; 1518a272653SPeter Holm } 1528a272653SPeter Holm int res = ev->state; 1538a272653SPeter Holm pthread_mutex_unlock(&ev->mu); 1548a272653SPeter Holm return res; 1558a272653SPeter Holm} 1568a272653SPeter Holm 1578a272653SPeter Holmstruct thread_t { 1588a272653SPeter Holm int created, call; 1598a272653SPeter Holm event_t ready, done; 1608a272653SPeter Holm}; 1618a272653SPeter Holm 1628a272653SPeter Holmstatic struct thread_t threads[16]; 1638a272653SPeter Holmstatic void execute_call(int call); 1648a272653SPeter Holmstatic int running; 1658a272653SPeter Holm 1668a272653SPeter Holmstatic void* thr(void* arg) 1678a272653SPeter Holm{ 1688a272653SPeter Holm struct thread_t* th = (struct thread_t*)arg; 1698a272653SPeter Holm for (;;) { 1708a272653SPeter Holm event_wait(&th->ready); 1718a272653SPeter Holm event_reset(&th->ready); 1728a272653SPeter Holm execute_call(th->call); 1738a272653SPeter Holm __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); 1748a272653SPeter Holm event_set(&th->done); 1758a272653SPeter Holm } 1768a272653SPeter Holm return 0; 1778a272653SPeter Holm} 1788a272653SPeter Holm 1798a272653SPeter Holmstatic void execute_one(void) 1808a272653SPeter Holm{ 1818a272653SPeter Holm int i, call, thread; 1828a272653SPeter Holm int collide = 0; 1838a272653SPeter Holmagain: 1848a272653SPeter Holm for (call = 0; call < 4; call++) { 1858a272653SPeter Holm for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0])); 1868a272653SPeter Holm thread++) { 1878a272653SPeter Holm struct thread_t* th = &threads[thread]; 1888a272653SPeter Holm if (!th->created) { 1898a272653SPeter Holm th->created = 1; 1908a272653SPeter Holm event_init(&th->ready); 1918a272653SPeter Holm event_init(&th->done); 1928a272653SPeter Holm event_set(&th->done); 1938a272653SPeter Holm thread_start(thr, th); 1948a272653SPeter Holm } 1958a272653SPeter Holm if (!event_isset(&th->done)) 1968a272653SPeter Holm continue; 1978a272653SPeter Holm event_reset(&th->done); 1988a272653SPeter Holm th->call = call; 1998a272653SPeter Holm __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); 2008a272653SPeter Holm event_set(&th->ready); 2018a272653SPeter Holm if (collide && (call % 2) == 0) 2028a272653SPeter Holm break; 2038a272653SPeter Holm event_timedwait(&th->done, 45); 2048a272653SPeter Holm break; 2058a272653SPeter Holm } 2068a272653SPeter Holm } 2078a272653SPeter Holm for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) 2088a272653SPeter Holm sleep_ms(1); 2098a272653SPeter Holm if (!collide) { 2108a272653SPeter Holm collide = 1; 2118a272653SPeter Holm goto again; 2128a272653SPeter Holm } 2138a272653SPeter Holm} 2148a272653SPeter Holm 2158a272653SPeter Holmstatic void execute_one(void); 2168a272653SPeter Holm 2178a272653SPeter Holm#define WAIT_FLAGS 0 2188a272653SPeter Holm 2198a272653SPeter Holmstatic void loop(void) 2208a272653SPeter Holm{ 221*7f658f99SPeter Holm int iter __unused; 2228a272653SPeter Holm for (iter = 0;; iter++) { 2238a272653SPeter Holm int pid = fork(); 2248a272653SPeter Holm if (pid < 0) 2258a272653SPeter Holm exit(1); 2268a272653SPeter Holm if (pid == 0) { 2278a272653SPeter Holm execute_one(); 2288a272653SPeter Holm exit(0); 2298a272653SPeter Holm } 2308a272653SPeter Holm int status = 0; 2318a272653SPeter Holm uint64_t start = current_time_ms(); 2328a272653SPeter Holm for (;;) { 2338a272653SPeter Holm if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) 2348a272653SPeter Holm break; 2358a272653SPeter Holm sleep_ms(1); 2368a272653SPeter Holm if (current_time_ms() - start < 5 * 1000) 2378a272653SPeter Holm continue; 2388a272653SPeter Holm kill_and_wait(pid, &status); 2398a272653SPeter Holm break; 2408a272653SPeter Holm } 2418a272653SPeter Holm } 2428a272653SPeter Holm} 2438a272653SPeter Holm 2448a272653SPeter Holmuint64_t r[1] = {0xffffffffffffffff}; 2458a272653SPeter Holm 2468a272653SPeter Holmvoid execute_call(int call) 2478a272653SPeter Holm{ 2488a272653SPeter Holm intptr_t res; 2498a272653SPeter Holm switch (call) { 2508a272653SPeter Holm case 0: 2518a272653SPeter Holm res = syscall(SYS_socket, 2ul, 1ul, 0); 2528a272653SPeter Holm if (res != -1) 2538a272653SPeter Holm r[0] = res; 2548a272653SPeter Holm break; 2558a272653SPeter Holm case 1: 2568a272653SPeter Holm memcpy((void*)0x20000040, 2578a272653SPeter Holm "bbr\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000" 2588a272653SPeter Holm "\000\000\000\000\000\000\000\000\000\000\000\000\000", 2598a272653SPeter Holm 32); 2608a272653SPeter Holm *(uint32_t*)0x20000060 = 0; 2618a272653SPeter Holm syscall(SYS_setsockopt, r[0], 6, 0x2000, 0x20000040ul, 0x24ul); 2628a272653SPeter Holm break; 2638a272653SPeter Holm case 2: 2648a272653SPeter Holm *(uint8_t*)0x20000180 = 0x10; 2658a272653SPeter Holm *(uint8_t*)0x20000181 = 2; 2668a272653SPeter Holm *(uint16_t*)0x20000182 = htobe16(0x4e22); 2678a272653SPeter Holm *(uint32_t*)0x20000184 = htobe32(0xfff); 2688a272653SPeter Holm *(uint8_t*)0x20000188 = 0; 2698a272653SPeter Holm *(uint8_t*)0x20000189 = 0; 2708a272653SPeter Holm *(uint8_t*)0x2000018a = 0; 2718a272653SPeter Holm *(uint8_t*)0x2000018b = 0; 2728a272653SPeter Holm *(uint8_t*)0x2000018c = 0; 2738a272653SPeter Holm *(uint8_t*)0x2000018d = 0; 2748a272653SPeter Holm *(uint8_t*)0x2000018e = 0; 2758a272653SPeter Holm *(uint8_t*)0x2000018f = 0; 2768a272653SPeter Holm syscall(SYS_connect, r[0], 0x20000180ul, 0x10ul); 2778a272653SPeter Holm break; 2788a272653SPeter Holm case 3: 2798a272653SPeter Holm syscall(SYS_listen, r[0], 0); 2808a272653SPeter Holm break; 2818a272653SPeter Holm } 2828a272653SPeter Holm} 2838a272653SPeter Holmint main(void) 2848a272653SPeter Holm{ 2858a272653SPeter Holm syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul); 2868a272653SPeter Holm loop(); 2878a272653SPeter Holm return 0; 2888a272653SPeter Holm} 2898a272653SPeter HolmEOF 2908a272653SPeter Holmmycc -o /tmp/syzkaller11 -Wall -Wextra -O2 /tmp/syzkaller11.c -lpthread || 2918a272653SPeter Holm exit 1 2928a272653SPeter Holm 2938a272653SPeter Holm(cd /tmp; ./syzkaller11) & 2948a272653SPeter Holmsleep 60 2958a272653SPeter Holmpkill -9 syzkaller11 2968a272653SPeter Holmwait 2978a272653SPeter Holm 2988a272653SPeter Holmrm -f /tmp/syzkaller11 /tmp/syzkaller11.c /tmp/syzkaller11.core 2998a272653SPeter Holmexit 0 300