[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 17.286182] audit: type=1400 audit(1520497323.513:6): avc: denied { map } for pid=4124 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 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.1' (ECDSA) to the list of known hosts. syzkaller login: [ 23.563882] audit: type=1400 audit(1520497329.791:7): avc: denied { map } for pid=4138 comm="syz-execprog" path="/root/syz-execprog" dev="sda1" ino=16479 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 2018/03/08 08:22:10 parsed 1 programs 2018/03/08 08:22:10 executed programs: 0 [ 23.813361] audit: type=1400 audit(1520497330.041:8): avc: denied { map } for pid=4138 comm="syz-execprog" path="/root/syzkaller-shm897894953" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1 [ 23.829062] IPVS: ftp: loaded support on port[0] = 21 [ 23.868941] audit: type=1400 audit(1520497330.096:9): avc: denied { map } for pid=4147 comm="syz-executor0" path="/dev/ashmem" dev="devtmpfs" ino=144 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 23.869314] [ 23.895013] ====================================================== [ 23.901301] WARNING: possible circular locking dependency detected [ 23.907584] 4.16.0-rc4+ #255 Not tainted [ 23.911612] ------------------------------------------------------ [ 23.917896] syz-executor0/4147 is trying to acquire lock: [ 23.923399] (&mm->mmap_sem){++++}, at: [<000000002421e3d4>] __might_fault+0xe0/0x1d0 [ 23.931346] [ 23.931346] but task is already holding lock: [ 23.937280] (ashmem_mutex){+.+.}, at: [<0000000085585a88>] ashmem_ioctl+0x3db/0x11b0 [ 23.945220] [ 23.945220] which lock already depends on the new lock. [ 23.945220] [ 23.953501] [ 23.953501] the existing dependency chain (in reverse order) is: [ 23.961089] [ 23.961089] -> #1 (ashmem_mutex){+.+.}: [ 23.966518] __mutex_lock+0x16f/0x1a80 [ 23.970900] mutex_lock_nested+0x16/0x20 [ 23.975452] ashmem_mmap+0x53/0x410 [ 23.979570] mmap_region+0xa99/0x15a0 [ 23.983858] do_mmap+0x6c0/0xe00 [ 23.987713] vm_mmap_pgoff+0x1de/0x280 [ 23.992090] SyS_mmap_pgoff+0x462/0x5f0 [ 23.996555] do_fast_syscall_32+0x3ec/0xf9f [ 24.001366] entry_SYSENTER_compat+0x70/0x7f [ 24.006261] [ 24.006261] -> #0 (&mm->mmap_sem){++++}: [ 24.011774] lock_acquire+0x1d5/0x580 [ 24.016065] __might_fault+0x13a/0x1d0 [ 24.020441] _copy_from_user+0x2c/0x110 [ 24.024902] ashmem_ioctl+0x438/0x11b0 [ 24.029277] compat_ashmem_ioctl+0x3e/0x50 [ 24.033999] compat_SyS_ioctl+0x151/0x2a30 [ 24.038726] do_fast_syscall_32+0x3ec/0xf9f [ 24.043535] entry_SYSENTER_compat+0x70/0x7f [ 24.048427] [ 24.048427] other info that might help us debug this: [ 24.048427] [ 24.056532] Possible unsafe locking scenario: [ 24.056532] [ 24.062557] CPU0 CPU1 [ 24.067213] ---- ---- [ 24.071849] lock(ashmem_mutex); [ 24.075271] lock(&mm->mmap_sem); [ 24.081297] lock(ashmem_mutex); [ 24.087232] lock(&mm->mmap_sem); [ 24.090737] [ 24.090737] *** DEADLOCK *** [ 24.090737] [ 24.096763] 1 lock held by syz-executor0/4147: [ 24.101308] #0: (ashmem_mutex){+.+.}, at: [<0000000085585a88>] ashmem_ioctl+0x3db/0x11b0 [ 24.109684] [ 24.109684] stack backtrace: [ 24.114148] CPU: 1 PID: 4147 Comm: syz-executor0 Not tainted 4.16.0-rc4+ #255 [ 24.121384] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.130710] Call Trace: [ 24.133269] dump_stack+0x194/0x24d [ 24.136868] ? arch_local_irq_restore+0x53/0x53 [ 24.141509] print_circular_bug.isra.38+0x2cd/0x2dc [ 24.146492] ? save_trace+0xe0/0x2b0 [ 24.150173] __lock_acquire+0x30a8/0x3e00 [ 24.154291] ? ashmem_ioctl+0x3db/0x11b0 [ 24.158324] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 24.163481] ? __might_sleep+0x95/0x190 [ 24.167424] ? ashmem_ioctl+0x3db/0x11b0 [ 24.171454] ? __mutex_lock+0x16f/0x1a80 [ 24.175481] ? ashmem_ioctl+0x3db/0x11b0 [ 24.179510] ? ashmem_ioctl+0x3db/0x11b0 [ 24.183538] ? lock_downgrade+0x980/0x980 [ 24.187654] ? mutex_lock_io_nested+0x1900/0x1900 [ 24.192463] ? lock_release+0xa40/0xa40 [ 24.196407] ? do_futex+0x86f/0x22a0 [ 24.200092] ? vma_set_page_prot+0x16b/0x230 [ 24.204471] ? avc_ss_reset+0x110/0x110 [ 24.208417] lock_acquire+0x1d5/0x580 [ 24.212192] ? lock_acquire+0x1d5/0x580 [ 24.216149] ? __might_fault+0xe0/0x1d0 [ 24.220094] ? userfaultfd_unmap_complete+0x327/0x510 [ 24.225252] ? lock_release+0xa40/0xa40 [ 24.229195] ? check_same_owner+0x320/0x320 [ 24.233485] ? __might_sleep+0x95/0x190 [ 24.237428] __might_fault+0x13a/0x1d0 [ 24.241285] ? __might_fault+0xe0/0x1d0 [ 24.245229] _copy_from_user+0x2c/0x110 [ 24.249170] ashmem_ioctl+0x438/0x11b0 [ 24.253037] ? selinux_file_ioctl+0x444/0x690 [ 24.257504] ? __fget_light+0x2b2/0x3c0 [ 24.261447] ? ashmem_release+0x190/0x190 [ 24.265561] ? perf_trace_sched_switch+0x779/0xf60 [ 24.270460] ? compat_SyS_futex+0x288/0x380 [ 24.274753] compat_ashmem_ioctl+0x3e/0x50 [ 24.278956] compat_SyS_ioctl+0x151/0x2a30 [ 24.283162] ? do_fast_syscall_32+0x156/0xf9f [ 24.287630] ? ashmem_ioctl+0x11b0/0x11b0 [ 24.291746] ? do_ioctl+0x60/0x60 [ 24.295172] do_fast_syscall_32+0x3ec/0xf9f [ 24.299462] ? do_int80_syscall_32+0x9c0/0x9c0 [ 24.304016] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 24.308743] ? syscall_return_slowpath+0x2ac/0x550 [ 24.313642] ? prepare_exit_to_usermode+0x350/0x350 [ 24.318630] ? sysret32_from_system_call+0x5/0x3c [ 24.323442] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 24.328252] entry_SYSENTER_compat+0x70/0x7f [ 24.332628] RIP: 0023:0xf7f5ac99 [ 24.335958] RSP: 002b:00000000ff8cd70c EFLAGS: 00000282 ORIG_RAX: 0000000000000036 [ 24.343633] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000007709 [ 24.350872] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 24.358112] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 24.365348] R10: 0000000000000000 R11: 0000000000000000 R12: 00000