[ OK ] Started OpenBSD Secure Shell server. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.123' (ECDSA) to the list of known hosts. 2021/09/05 19:30:25 fuzzer started 2021/09/05 19:30:25 connecting to host at 10.128.0.163:46721 2021/09/05 19:30:25 checking machine... 2021/09/05 19:30:25 checking revisions... 2021/09/05 19:30:25 testing simple program... syzkaller login: [ 20.200993][ T25] audit: type=1400 audit(1630870225.384:8): avc: denied { execmem } for pid=1767 comm="syz-executor.0" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 20.244760][ T1768] cgroup: Unknown subsys name 'perf_event' [ 20.251488][ T1768] cgroup: Unknown subsys name 'net_cls' [ 20.408124][ T1816] ================================================================== [ 20.417329][ T1816] BUG: KCSAN: data-race in cgroup_rstat_flush_locked / cgroup_rstat_updated [ 20.426798][ T1816] [ 20.429142][ T1816] write to 0xffffe8ffffd193c0 of 8 bytes by task 247 on cpu 0: [ 20.436799][ T1816] cgroup_rstat_flush_locked+0x282/0x7f0 [ 20.443147][ T1816] cgroup_rstat_flush_irqsafe+0x24/0x40 [ 20.448786][ T1816] flush_memcg_stats_work+0x34/0x60 [ 20.454083][ T1816] process_one_work+0x402/0x910 [ 20.458976][ T1816] worker_thread+0x636/0xae0 [ 20.463559][ T1816] kthread+0x262/0x280 [ 20.467624][ T1816] ret_from_fork+0x1f/0x30 [ 20.472110][ T1816] [ 20.474411][ T1816] read to 0xffffe8ffffd193c0 of 8 bytes by task 1816 on cpu 1: [ 20.481935][ T1816] cgroup_rstat_updated+0x53/0x1c0 [ 20.487208][ T1816] __mod_lruvec_state+0x7c/0xe0 [ 20.492044][ T1816] __mod_lruvec_page_state+0xd2/0x120 [ 20.497569][ T1816] page_add_file_rmap+0x4a/0x60 [ 20.502416][ T1816] do_set_pte+0x268/0x410 [ 20.506720][ T1816] filemap_map_pages+0x51d/0x870 [ 20.511722][ T1816] handle_mm_fault+0xae0/0x1530 [ 20.516558][ T1816] do_user_addr_fault+0x609/0xbe0 [ 20.521959][ T1816] exc_page_fault+0x91/0x220 [ 20.526542][ T1816] asm_exc_page_fault+0x1e/0x30 [ 20.531464][ T1816] [ 20.533774][ T1816] value changed: 0xffff888100e06010 -> 0x0000000000000000 [ 20.541732][ T1816] [ 20.544121][ T1816] Reported by Kernel Concurrency Sanitizer on: [ 20.550421][ T1816] CPU: 1 PID: 1816 Comm: modprobe Not tainted 5.14.0-syzkaller #0 [ 20.558687][ T1816] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 20.568966][ T1816] ================================================================== 2021/09/05 19:30:26 building call list... [ 22.736921][ T25] audit: type=1400 audit(1630870227.917:9): avc: denied { create } for pid=1757 comm="syz-fuzzer" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=dccp_socket permissive=1