[....] Starting enhanced syslogd: rsyslogd[ 12.852648] audit: type=1400 audit(1519637511.041:4): avc: denied { syslog } for pid=3652 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1
[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
Starting mcstransd:
[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
Debian GNU/Linux 7 syzkaller ttyS0
Warning: Permanently added '10.128.0.18' (ECDSA) to the list of known hosts.
executing program
syzkaller login: [ 26.829044]
[ 26.830705] ======================================================
[ 26.836992] [ INFO: possible circular locking dependency detected ]
[ 26.843370] 4.9.84-ga9d0273 #44 Not tainted
[ 26.847663] -------------------------------------------------------
[ 26.854049] syzkaller022277/3808 is trying to acquire lock:
[ 26.859729] (&mm->mmap_sem){++++++}, at: [<ffffffff814c2714>] __might_fault+0xe4/0x1d0
[ 26.868221] but task is already holding lock:
[ 26.872861] (ashmem_mutex){+.+.+.}, at: [<ffffffff82d4aef1>] ashmem_ioctl+0x371/0xfe0
[ 26.881258] which lock already depends on the new lock.
[ 26.881258]
[ 26.888250]
[ 26.888250] the existing dependency chain (in reverse order) is:
[ 26.895839]
-> #1 (ashmem_mutex){+.+.+.}:
[ 26.900606] lock_acquire+0x12e/0x410
[ 26.904899] mutex_lock_nested+0xbb/0x870
[ 26.909538] ashmem_mmap+0x53/0x400
[ 26.913657] mmap_region+0x7dd/0xfd0
[ 26.917860] do_mmap+0x57b/0xbe0
[ 26.921722] vm_mmap_pgoff+0x16b/0x1b0
[ 26.926099] SyS_mmap_pgoff+0x33f/0x560
[ 26.930566] SyS_mmap+0x16/0x20
[ 26.934333] do_syscall_64+0x1a4/0x490
[ 26.938710] entry_SYSCALL_64_after_swapgs+0x47/0xc5
[ 26.944298]
-> #0 (&mm->mmap_sem){++++++}:
[ 26.949147] __lock_acquire+0x2bf9/0x3640
[ 26.953785] lock_acquire+0x12e/0x410
[ 26.958077] __might_fault+0x14a/0x1d0
[ 26.962453] ashmem_ioctl+0x3c0/0xfe0
[ 26.966764] do_vfs_ioctl+0x1aa/0x1140
[ 26.971141] SyS_ioctl+0x8f/0xc0
[ 26.974995] do_syscall_64+0x1a4/0x490
[ 26.979374] entry_SYSCALL_64_after_swapgs+0x47/0xc5
[ 26.984965]
[ 26.984965] other info that might help us debug this:
[ 26.984965]
[ 26.993074] Possible unsafe locking scenario:
[ 26.993074]
[ 26.999101] CPU0 CPU1
[ 27.003736] ---- ----
[ 27.008372] lock(ashmem_mutex);
[ 27.012034] lock(&mm->mmap_sem);
[ 27.018299] lock(ashmem_mutex);
[ 27.024476] lock(&mm->mmap_sem);
[ 27.028222]
[ 27.028222] *** DEADLOCK ***
[ 27.028222]
[ 27.034254] 1 lock held by syzkaller022277/3808:
[ 27.038979] #0: (ashmem_mutex){+.+.+.}, at: [<ffffffff82d4aef1>] ashmem_ioctl+0x371/0xfe0
[ 27.047922]
[ 27.047922] stack backtrace:
[ 27.052393] CPU: 0 PID: 3808 Comm: syzkaller022277 Not tainted 4.9.84-ga9d0273 #44
[ 27.060069] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 27.069397] ffff8801d8d2f908 ffffffff81d956b9 ffffffff853a2cd0 ffffffff853a2cd0
[ 27.077387] ffffffff853c2f80 ffff8801d97908d8 ffff8801d9790000 ffff8801d8d2f950
[ 27.085372] ffffffff812387f1 ffff8801d97908d8 00000000d97908b0 ffff8801d97908d8
[ 27.093356] Call Trace:
[ 27.095919] [<ffffffff81d956b9>] dump_stack+0xc1/0x128
[ 27.101258] [<ffffffff812387f1>] print_circular_bug+0x271/0x310
[ 27.107376] [<ffffffff8123ec29>] __lock_acquire+0x2bf9/0x3640
[ 27.113319] [<ffffffff8123c030>] ? debug_check_no_locks_freed+0x2c0/0x2c0
[ 27.120304] [<ffffffff8123c030>] ? debug_check_no_locks_freed+0x2c0/0x2c0
[ 27.127297] [<ffffffff8123b41f>] ? mark_held_locks+0xaf/0x100
[ 27.133239] [<ffffffff838abb93>] ? mutex_lock_nested+0x5e3/0x870
[ 27.139443] [<ffffffff81234d01>] ? __lock_is_held+0xa1/0xf0
[ 27.145212] [<ffffffff812400ae>] lock_acquire+0x12e/0x410
[ 27.150807] [<ffffffff814c2714>] ? __might_fault+0xe4/0x1d0
[ 27.156577] [<ffffffff814c277a>] __might_fault+0x14a/0x1d0
[ 27.162259] [<ffffffff814c2714>] ? __might_fault+0xe4/0x1d0
[ 27.168032] [<ffffffff82d4af40>] ashmem_ioctl+0x3c0/0xfe0
[ 27.173627] [<ffffffff814e27a1>] ? vma_wants_writenotify+0x51/0x380
[ 27.180092] [<ffffffff814e2bdf>] ? vma_set_page_prot+0x10f/0x180
[ 27.186296] [<ffffffff82d4ab80>] ? get_name+0x250/0x250
[ 27.191718] [<ffffffff814e6e41>] ? mmap_region+0x161/0xfd0
[ 27.197401] [<ffffffff82d4ab80>] ? get_name+0x250/0x250
[ 27.202823] [<ffffffff815ae88a>] do_vfs_ioctl+0x1aa/0x1140
[ 27.208506] [<ffffffff815ae6e0>] ? ioctl_preallocate+0x220/0x220
[ 27.214708] [<ffffffff81beb235>] ? selinux_file_ioctl+0x355/0x530
[ 27.220997] [<ffffffff81beaee0>] ? selinux_capable+0x40/0x40
[ 27.226858] [<ffffffff815754a2>] ? fput+0xd