[ 39.258296] audit: type=1800 audit(1572685881.119:31): pid=7445 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2469 res=0 [ 39.280482] audit: type=1800 audit(1572685881.119:32): pid=7445 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="ssh" dev="sda1" ino=2450 res=0 Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.44' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 47.480195] kauditd_printk_skb: 3 callbacks suppressed [ 47.480210] audit: type=1400 audit(1572685889.399:36): avc: denied { map } for pid=7632 comm="syz-executor957" path="/root/syz-executor957245890" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 47.483453] [ 47.513532] ============================= [ 47.517659] WARNING: suspicious RCU usage [ 47.521791] 4.19.81 #0 Not tainted [ 47.525313] ----------------------------- [ 47.529533] include/linux/radix-tree.h:241 suspicious rcu_dereference_check() usage! [ 47.537520] [ 47.537520] other info that might help us debug this: [ 47.537520] [ 47.546105] [ 47.546105] rcu_scheduler_active = 2, debug_locks = 1 [ 47.552859] 2 locks held by syz-executor957/7632: [ 47.557682] #0: 0000000035a203a2 (&sb->s_type->i_mutex_key#12){+.+.}, at: memfd_fcntl+0x235/0x1750 [ 47.566885] #1: 000000006ab08fd8 (&(&(&mapping->i_pages)->xa_lock)->rlock){-...}, at: memfd_fcntl+0x4bc/0x1750 [ 47.577123] [ 47.577123] stack backtrace: [ 47.581615] CPU: 1 PID: 7632 Comm: syz-executor957 Not tainted 4.19.81 #0 [ 47.588621] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.597965] Call Trace: [ 47.600572] dump_stack+0x172/0x1f0 [ 47.604972] lockdep_rcu_suspicious+0x153/0x15d [ 47.609646] memfd_fcntl+0xfdf/0x1750 [ 47.613449] ? vfs_write+0x2f0/0x560 [ 47.617161] ? find_held_lock+0x35/0x130 [ 47.621224] ? vfs_write+0x2f0/0x560 [ 47.624945] ? memfd_file_seals_ptr+0x160/0x160 [ 47.629616] ? check_preemption_disabled+0x48/0x290 [ 47.634624] do_fcntl+0x200/0x1020 [ 47.638152] ? f_getown+0xc0/0xc0 [ 47.641592] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 47.647116] ? ksys_write+0x1f1/0x2d0 [ 47.650905] ? __sanitizer_cov_trace_switch+0x49/0x80 [ 47.656111] ? selinux_file_fcntl+0x74/0x140 [ 47.660514] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 47.666038] ? security_file_fcntl+0x8d/0xc0 [ 47.670437] __x64_sys_fcntl+0x16d/0x1e0 [ 47.674509] do_syscall_64+0xfd/0x620 [ 47.678325] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 47.683614] RIP: 0033:0x440169 [ 47.686792] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 47.705703] RSP: 002b:00007fff3661e7d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000048 [ 47.713667] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440169 [ 47.720924] RDX: 0000000000000008 RSI: 0000000000000409 RDI: 0000000000000003 [ 47.728205] RBP: 00000000006ca018