[ 43.493088][ T25] audit: type=1800 audit(1555814384.223:30): pid=7819 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 49.371153][ T25] kauditd_printk_skb: 4 callbacks suppressed [ 49.371168][ T25] audit: type=1400 audit(1555814390.123:35): avc: denied { map } for pid=7992 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.10.53' (ECDSA) to the list of known hosts. executing program [ 55.777774][ T25] audit: type=1400 audit(1555814396.533:36): avc: denied { map } for pid=8004 comm="syz-executor256" path="/root/syz-executor256505547" dev="sda1" ino=15902 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 55.831732][ T8006] ------------[ cut here ]------------ [ 55.839283][ T8006] percpu_ref_kill_and_confirm called more than once on io_ring_ctx_ref_free! [ 55.839708][ T8006] WARNING: CPU: 1 PID: 8006 at lib/percpu-refcount.c:335 percpu_ref_kill_and_confirm+0x341/0x3b0 [ 55.858937][ T8006] Kernel panic - not syncing: panic_on_warn set ... [ 55.865521][ T8006] CPU: 1 PID: 8006 Comm: syz-executor256 Not tainted 5.1.0-rc5+ #77 [ 55.873495][ T8006] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 55.883537][ T8006] Call Trace: [ 55.886819][ T8006] dump_stack+0x172/0x1f0 [ 55.891135][ T8006] ? percpu_ref_kill_and_confirm+0x340/0x3b0 [ 55.897142][ T8006] panic+0x2cb/0x65c [ 55.901043][ T8006] ? __warn_printk+0xf3/0xf3 [ 55.905618][ T8006] ? percpu_ref_kill_and_confirm+0x341/0x3b0 [ 55.911589][ T8006] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.917813][ T8006] ? __warn.cold+0x5/0x45 [ 55.922153][ T8006] ? __warn+0xe8/0x1d0 [ 55.926207][ T8006] ? percpu_ref_kill_and_confirm+0x341/0x3b0 [ 55.932165][ T8006] __warn.cold+0x20/0x45 [ 55.936387][ T8006] ? vprintk_emit+0x1ce/0x6d0 [ 55.941194][ T8006] ? percpu_ref_kill_and_confirm+0x341/0x3b0 [ 55.947177][ T8006] report_bug+0x263/0x2b0 [ 55.951490][ T8006] do_error_trap+0x11b/0x200 [ 55.956075][ T8006] do_invalid_op+0x37/0x50 [ 55.960492][ T8006] ? percpu_ref_kill_and_confirm+0x341/0x3b0 [ 55.966464][ T8006] invalid_op+0x14/0x20 [ 55.970601][ T8006] RIP: 0010:percpu_ref_kill_and_confirm+0x341/0x3b0 [ 55.977184][ T8006] Code: 42 e0 2a 06 01 48 89 fa 48 c1 ea 03 80 3c 02 00 75 76 49 8b 54 24 10 48 c7 c6 a0 71 a1 87 48 c7 c7 40 71 a1 87 e8 ad 92 13 fe <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 [ 55.997050][ T8006] RSP: 0018:ffff8880941b7cf0 EFLAGS: 00010082 [ 56.003097][ T8006] RAX: 0000000000000000 RBX: 0000607f5142f90b RCX: 0000000000000000 [ 56.011064][ T8006] RDX: 0000000000000000 RSI: ffffffff815afcf6 RDI: ffffed1012836f90 [ 56.019018][ T8006] RBP: ffff8880941b7d20 R08: ffff8880a42f6180 R09: fffffbfff1133639 [ 56.026966][ T8006] R10: fffffbfff1133638 R11: ffffffff8899b1c3 R12: ffff8880a0d183c0 [ 56.034916][ T8006] R13: ffff8880a0d183c8 R14: 0000000000000286 R15: 0000000000000000 [ 56.042882][ T8006] ? vprintk_func+0x86/0x189 [ 56.047456][ T8006] __io_uring_register+0xa7/0x1fe0 [ 56.052545][ T8006] ? __mutex_lock+0x3cd/0x1310 [ 56.057286][ T8006] ? __x64_sys_io_uring_register+0x182/0x1f0 [ 56.063246][ T8006] ? mutex_trylock+0x1e0/0x1e0 [ 56.067990][ T8006] ? io_sq_wq_submit_work+0x10f0/0x10f0 [ 56.073516][ T8006] ? kasan_check_write+0x14/0x20 [ 56.078437][ T8006] __x64_sys_io_uring_register+0x193/0x1f0 [ 56.084221][ T8006] do_syscall_64+0x103/0x610 [ 56.088796][ T8006] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 56.094665][ T8006] RIP: 0033:0x445eb9 [ 56.098539][ T8006] Code: e8 ac b8 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 56.118122][ T8006] RSP: 002b:00007f029df18ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab [ 56.126520][ T8006] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000445eb9 [ 56.134468][ T8006] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003 [ 56.142416][ T8006] RBP: 00000000006dac30 R08: 00007f029df19700 R09: 0000000000000000 [ 56.150384][ T8006] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dac3c [ 56.158331][ T8006] R13: 00007ffd29ca4cef R14: 00007f029df199c0 R15: 20c49ba5e353f7cf [ 56.167230][ T8006] Kernel Offset: disabled [ 56.171624][ T8006] Rebooting in 86400 seconds..