[ 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 '10.128.0.74' (ECDSA) to the list of known hosts. 2021/09/05 18:04:30 fuzzer started 2021/09/05 18:04:30 connecting to host at 10.128.0.163:40873 2021/09/05 18:04:30 checking machine... 2021/09/05 18:04:30 checking revisions... 2021/09/05 18:04:30 testing simple program... syzkaller login: [ 18.534072][ T25] audit: type=1400 audit(1630865070.327:8): avc: denied { execmem } for pid=1785 comm="syz-executor.0" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 18.564234][ T1786] cgroup: Unknown subsys name 'perf_event' [ 18.571064][ T1786] cgroup: Unknown subsys name 'net_cls' [ 18.848122][ T1880] ================================================================== [ 18.857305][ T1880] BUG: KCSAN: data-race in cgroup_rstat_flush_locked / cgroup_rstat_updated [ 18.866500][ T1880] [ 18.868907][ T1880] write to 0xffffe8ffffc19460 of 8 bytes by task 377 on cpu 1: [ 18.876808][ T1880] cgroup_rstat_flush_locked+0x282/0x7f0 [ 18.882793][ T1880] cgroup_rstat_flush_irqsafe+0x24/0x40 [ 18.889054][ T1880] flush_memcg_stats_work+0x34/0x60 [ 18.894290][ T1880] process_one_work+0x402/0x910 [ 18.899551][ T1880] worker_thread+0x636/0xae0 [ 18.904983][ T1880] kthread+0x262/0x280 [ 18.909821][ T1880] ret_from_fork+0x1f/0x30 [ 18.915354][ T1880] [ 18.917839][ T1880] read to 0xffffe8ffffc19460 of 8 bytes by task 1880 on cpu 0: [ 18.926484][ T1880] cgroup_rstat_updated+0x53/0x1c0 [ 18.932401][ T1880] __mod_lruvec_state+0x7c/0xe0 [ 18.937764][ T1880] __mod_lruvec_page_state+0xd2/0x120 [ 18.943808][ T1880] page_remove_rmap+0x111/0x230 [ 18.949732][ T1880] zap_pte_range+0x6ad/0xe00 [ 18.955027][ T1880] unmap_page_range+0x2dc/0x3d0 [ 18.960670][ T1880] unmap_single_vma+0x157/0x210 [ 18.965657][ T1880] unmap_vmas+0xc0/0x170 [ 18.970006][ T1880] exit_mmap+0x22d/0x460 [ 18.974239][ T1880] __mmput+0x27/0x1d0 [ 18.978401][ T1880] mmput+0x3d/0x50 [ 18.982223][ T1880] exit_mm+0x2f7/0x3f0 [ 18.986748][ T1880] do_exit+0x3ef/0x14a0 [ 18.991065][ T1880] do_group_exit+0xa4/0x1a0 [ 18.995752][ T1880] __do_sys_exit_group+0xb/0x10 [ 19.000873][ T1880] __se_sys_exit_group+0x5/0x10 [ 19.005866][ T1880] __x64_sys_exit_group+0x16/0x20 [ 19.010973][ T1880] do_syscall_64+0x3d/0x90 [ 19.015994][ T1880] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 19.022657][ T1880] [ 19.025086][ T1880] value changed: 0xffff888100b08010 -> 0x0000000000000000 [ 19.032637][ T1880] [ 19.035076][ T1880] Reported by Kernel Concurrency Sanitizer on: [ 19.041583][ T1880] CPU: 0 PID: 1880 Comm: modprobe Not tainted 5.14.0-syzkaller #0 [ 19.049701][ T1880] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 19.060003][ T1880] ================================================================== 2021/09/05 18:04:31 building call list... [ 21.070963][ T25] audit: type=1400 audit(1630865072.858:9): avc: denied { create } for pid=1773 comm="syz-fuzzer" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=dccp_socket permissive=1