[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m[ 16.819078] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.430373] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available) [ 20.834055] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available) [ 21.730755] random: sshd: uninitialized urandom read (32 bytes read, 107 bits of entropy available) [ 21.900248] random: sshd: uninitialized urandom read (32 bytes read, 111 bits of entropy available) Warning: Permanently added '10.128.0.57' (ECDSA) to the list of known hosts. [ 27.263854] random: sshd: uninitialized urandom read (32 bytes read, 117 bits of entropy available) executing program [ 27.355843] ================================================================== [ 27.363241] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 27.369892] Read of size 8 at addr ffff8801d1096838 by task syzkaller278471/3319 [ 27.377394] [ 27.379005] CPU: 0 PID: 3319 Comm: syzkaller278471 Not tainted 4.4.112-gca0ebb4 #22 [ 27.386775] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.396111] 0000000000000000 a4e413801219c40e ffff8801d0bcf850 ffffffff81d056fd [ 27.404081] ffffea0007442580 ffff8801d1096838 0000000000000000 ffff8801d1096838 [ 27.412048] 0000000000000000 ffff8801d0bcf888 ffffffff814fd953 ffff8801d1096838 [ 27.420041] Call Trace: [ 27.422619] [] dump_stack+0xc1/0x124 [ 27.428691] [] print_address_description+0x73/0x260 [ 27.435328] [] kasan_report+0x285/0x370 [ 27.440924] [] ? __lock_acquire+0x387e/0x4b50 [ 27.447042] [] __asan_report_load8_noabort+0x14/0x20 [ 27.453763] [] __lock_acquire+0x387e/0x4b50 [ 27.459704] [] ? __lock_acquire+0xb5f/0x4b50 [ 27.465733] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.472716] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.479528] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.486512] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.493497] [] lock_acquire+0x15e/0x460 [ 27.499107] [] ? remove_wait_queue+0x14/0x40 [ 27.505138] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 27.511433] [] ? remove_wait_queue+0x14/0x40 [ 27.517465] [] remove_wait_queue+0x14/0x40 [ 27.523334] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 27.530332] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 27.537586] [] ? ep_free+0x1c0/0x1c0 [ 27.542918] [] ep_free+0x93/0x1c0 [ 27.547991] [] ? ep_free+0x1c0/0x1c0 [ 27.553337] [] ep_eventpoll_release+0x44/0x60 [ 27.559455] [] __fput+0x233/0x6d0 [ 27.564528] [] ____fput+0x15/0x20 [ 27.569603] [] task_work_run+0x104/0x180 [ 27.575301] [] do_exit+0x871/0x2a20 [ 27.580570] [] ? handle_mm_fault+0x192d/0x3190 [ 27.586777] [] ? handle_mm_fault+0x3f2/0x3190 [ 27.592905] [] ? release_task+0x1240/0x1240 [ 27.598858] [] do_group_exit+0x108/0x320 [ 27.604540] [] SyS_exit_group+0x1d/0x20 [ 27.610149] [] ? do_group_exit+0x320/0x320 [ 27.616014] [] do_fast_syscall_32+0x314/0x890 [ 27.622134] [] sysenter_flags_fixed+0xd/0x17 [ 27.628162] [ 27.629774] Allocated by task 3319: [ 27.633370] [] save_stack_trace+0x26/0x50 [ 27.639256] [] save_stack+0x43/0xd0 [ 27.644622] [] kasan_kmalloc+0xad/0xe0 [ 27.650245] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 27.656824] [] binder_get_thread+0x181/0x7a0 [ 27.662974] [] binder_poll+0x4a/0x210 [ 27.668513] [] SyS_epoll_ctl+0x10b1/0x2050 [ 27.674488] [] do_fast_syscall_32+0x314/0x890 [ 27.680718] [] sysenter_flags_fixed+0xd/0x17 [ 27.686861] [ 27.688458] Freed by task 3319: [ 27.691712] [] save_stack_trace+0x26/0x50 [ 27.697594] [] save_stack+0x43/0xd0 [ 27.702956] [] kasan_slab_free+0x72/0xc0 [ 27.708750] [] kfree+0xfc/0x300 [ 27.713762] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 27.720526] [] binder_thread_release+0x27d/0x540 [ 27.727030] [] binder_ioctl+0xb94/0x12e0 [ 27.732827] [] compat_SyS_ioctl+0x28a/0x2540 [ 27.738969] [] do_fast_syscall_32+0x314/0x890 [ 27.745196] [] sysenter_flags_fixed+0xd/0x17 [ 27.751341] [ 27.752937] The buggy address belongs to the object at ffff8801d1096780 [ 27.752937] which belongs to the cache kmalloc-512 of size 512 [ 27.765562] The buggy address is located 184 bytes inside of [ 27.765562] 512-byte region [ffff8801d1096780, ffff8801d1096980) [ 27.777413] The buggy address belongs to the page: [ 27.784736] BUG: unable to handle kernel NULL pointer dereference at (null) [ 27.792940] IP: [< (null)>] (null) [ 27.798213] PGD 0 [ 27.800443] Oops: 0010 [#1] PREEMPT SMP KASAN [ 27.805374] Dumping ftrace buffer: [ 27.808883] (ftrace buffer empty) [ 27.812561] Modules linked in: [ 27.815839] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.112-gca0ebb4 #22 [ 27.822818] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.832153] task: ffff8801da3a97c0 task.stack: ffff8801da3b8000 [ 27.838174] RIP: 0010:[<0000000000000000>] [< (null)>] (null) [ 27.845881] RSP: 0018:ffff8801db307df0 EFLAGS: 00010006 [ 27.851306] RAX: ffff8801da3a97c0 RBX: ffff8801d0827df8 RCX: ffffffff812ac970 [ 27.858547] RDX: 0000000000010000 RSI: ffffffff839fdb20 RDI: ffff8801d0827df8 [ 27.865789] RBP: ffff8801db307ee0 R08: 1ffff1003ab71f92 R09: 0000000000000001 [ 27.873028] R10: 0000000000000000 R11: 1ffff1003b660f6a R12: 0000000000000000 [ 27.880266] R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8801db319640 [ 27.887505] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 27.895701] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 27.901550] CR2: 0000000000000000 CR3: 00000001d13de000 CR4: 0000000000160670 [ 27.908792] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 27.916031] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 27.923272] Stack: [ 27.925390] ffffffff812ac976 ffff88021fffd057 ffff88021fffd05b ffff88021fffd04f [ 27.933369] 1ffff1003b660fcb ffff8801db3196a0 ffffed003b660fca ffff8801db319700 [ 27.941327] 0303fc0000000001 ffff8801db319678 ffffed003b6632d4 ffff8801db319718 [ 27.949298] Call Trace: [ 27.951849] [ 27.953885] [] ? __hrtimer_run_queues+0x306/0xfe0 [ 27.960634] [] ? hrtimer_fixup_init+0x70/0x70 [ 27.966746] [] ? hrtimer_interrupt+0x131/0x440 [ 27.972945] [] hrtimer_interrupt+0x1a6/0x440 [ 27.978970] [] local_apic_timer_interrupt+0x6a/0xb0 [ 27.985607] [] smp_apic_timer_interrupt+0x76/0xa0 [ 27.992067] [] apic_timer_interrupt+0xa0/0xb0 [ 27.998176] [ 28.000209] [] ? native_safe_halt+0x6/0x10 [ 28.006351] [] ? trace_hardirqs_on+0xd/0x10 [ 28.012306] [] default_idle+0x55/0x3c0 [ 28.017811] [] arch_cpu_idle+0xa/0x10 [ 28.023233] [] default_idle_call+0x48/0x70 [ 28.029088] [] cpu_startup_entry+0x605/0x820 [ 28.035114] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.041932] [] ? call_cpuidle+0xe0/0xe0 [ 28.047525] [] ? clockevents_register_device+0x122/0x230 [ 28.054593] [] start_secondary+0x304/0x3e0 [ 28.060445] [] ? set_cpu_sibling_map+0x1040/0x1040 [ 28.066993] Code: Bad RIP value. [ 28.070650] RIP [< (null)>] (null) [ 28.076011] RSP [ 28.079604] CR2: 0000000000000000 [ 28.083027] ---[ end trace 64e108ee1daa6b4b ]--- [ 28.087749] Kernel panic - not syncing: Fatal exception in interrupt [ 29.235365] Shutting down cpus with NMI [ 29.240314] Dumping ftrace buffer: [ 29.243828] (ftrace buffer empty) [ 29.247506] Kernel Offset: disabled [ 29.251100] Rebooting in 86400 seconds..