[ 15.807211] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [....] 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 syzkaller login: [ 21.807363] random: sshd: uninitialized urandom read (32 bytes read, 38 bits of entropy available) [ 22.092508] random: sshd: uninitialized urandom read (32 bytes read, 38 bits of entropy available) [ 22.905772] random: sshd: uninitialized urandom read (32 bytes read, 94 bits of entropy available) [ 23.087269] random: sshd: uninitialized urandom read (32 bytes read, 99 bits of entropy available) Warning: Permanently added '10.128.15.198' (ECDSA) to the list of known hosts. [ 28.473011] random: sshd: uninitialized urandom read (32 bytes read, 106 bits of entropy available) executing program [ 28.573046] ================================================================== [ 28.580457] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 28.587091] Read of size 8 at addr ffff8801d2a4e5b8 by task syzkaller586581/3314 [ 28.594589] [ 28.596186] CPU: 1 PID: 3314 Comm: syzkaller586581 Not tainted 4.4.111-g3301b55 #17 [ 28.603956] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.613281] 0000000000000000 6d35f4bc087fc954 ffff8801d04e7850 ffffffff81d0509d [ 28.621286] ffffea00074a9380 ffff8801d2a4e5b8 0000000000000000 ffff8801d2a4e5b8 [ 28.629274] 0000000000000000 ffff8801d04e7888 ffffffff814fd433 ffff8801d2a4e5b8 [ 28.637245] Call Trace: [ 28.639805] [] dump_stack+0xc1/0x124 [ 28.645155] [] print_address_description+0x73/0x260 [ 28.651803] [] kasan_report+0x285/0x370 [ 28.657417] [] ? __lock_acquire+0x387e/0x4b50 [ 28.663553] [] __asan_report_load8_noabort+0x14/0x20 [ 28.670282] [] __lock_acquire+0x387e/0x4b50 [ 28.676218] [] ? __lock_acquire+0xb5f/0x4b50 [ 28.682252] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.689233] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.696053] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.703036] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.710013] [] lock_acquire+0x15e/0x460 [ 28.715607] [] ? remove_wait_queue+0x14/0x40 [ 28.721633] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 28.727916] [] ? remove_wait_queue+0x14/0x40 [ 28.733940] [] remove_wait_queue+0x14/0x40 [ 28.739794] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 28.746772] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 28.754010] [] ? ep_free+0x1c0/0x1c0 [ 28.759338] [] ep_free+0x93/0x1c0 [ 28.764405] [] ? ep_free+0x1c0/0x1c0 [ 28.769770] [] ep_eventpoll_release+0x44/0x60 [ 28.775887] [] __fput+0x233/0x6d0 [ 28.780964] [] ____fput+0x15/0x20 [ 28.786047] [] task_work_run+0x104/0x180 [ 28.791755] [] do_exit+0x871/0x2a20 [ 28.797005] [] ? handle_mm_fault+0x192d/0x3190 [ 28.803204] [] ? handle_mm_fault+0x3f2/0x3190 [ 28.809331] [] ? release_task+0x1240/0x1240 [ 28.815270] [] do_group_exit+0x108/0x320 [ 28.820969] [] SyS_exit_group+0x1d/0x20 [ 28.826567] [] ? do_group_exit+0x320/0x320 [ 28.832420] [] do_fast_syscall_32+0x314/0x890 [ 28.838534] [] sysenter_flags_fixed+0xd/0x17 [ 28.844562] [ 28.846167] Allocated by task 3314: [ 28.849779] [] save_stack_trace+0x26/0x50 [ 28.855658] [] save_stack+0x43/0xd0 [ 28.861028] [] kasan_kmalloc+0xad/0xe0 [ 28.866643] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 28.873220] [] binder_get_thread+0x181/0x7a0 [ 28.879369] [] binder_poll+0x4a/0x210 [ 28.884903] [] SyS_epoll_ctl+0x10b1/0x2050 [ 28.890868] [] do_fast_syscall_32+0x314/0x890 [ 28.897095] [] sysenter_flags_fixed+0xd/0x17 [ 28.903234] [ 28.904826] Freed by task 3314: [ 28.908076] [] save_stack_trace+0x26/0x50 [ 28.913954] [] save_stack+0x43/0xd0 [ 28.919312] [] kasan_slab_free+0x72/0xc0 [ 28.925102] [] kfree+0xfc/0x300 [ 28.930118] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 28.936878] [] binder_thread_release+0x27d/0x540 [ 28.943390] [] binder_ioctl+0xb94/0x12e0 [ 28.949181] [] compat_SyS_ioctl+0x28a/0x2540 [ 28.955325] [] do_fast_syscall_32+0x314/0x890 [ 28.961553] [] sysenter_flags_fixed+0xd/0x17 [ 28.968331] [ 28.969931] The buggy address belongs to the object at ffff8801d2a4e500 [ 28.969931] which belongs to the cache kmalloc-512 of size 512 [ 28.982554] The buggy address is located 184 bytes inside of [ 28.982554] 512-byte region [ffff8801d2a4e500, ffff8801d2a4e700) [ 28.994391] The buggy address belongs to the page: [ 30.482910] PANIC: double fault, error_code: 0x0 [ 30.487707] CPU: 1 PID: 3314 Comm: syzkaller586581 Not tainted 4.4.111-g3301b55 #17 [ 30.495479] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.504801] task: ffff8800b49f4740 task.stack: ffff8801d04e0000 [ 30.510825] RIP: 0010:[] [] dump_page_badflags+0x1a/0x250 [ 30.519666] RSP: 0018:ffff880100000000 EFLAGS: 00010086 [ 30.525082] RAX: ffff8800b49f4740 RBX: ffffea00074a9380 RCX: ffffffff8148f980 [ 30.532329] RDX: 0000000000000000 RSI: ffffffff838a83a0 RDI: ffffea00074a9380 [ 30.539567] RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000 [ 30.546802] R10: 0000000000000002 R11: fffffbfff0ad781e R12: 0000000000000000 [ 30.554043] R13: ffffffff838a83a0 R14: 0000000000000000 R15: 0000000000000000 [ 30.561279] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 30.569541] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 30.575390] CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670 [ 30.582629] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.589865] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.597107] Stack: [ 30.599221] [ 30.600812] Call Trace: [ 30.603358] [ 30.605383] Code: e2 06 00 e9 1d fd ff ff 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 56 41 55 49 89 f5 41 54 49 89 d4 53 48 89 fb 48 83 ec 08 61 06 ed ff 48 8d 7b 10 48 b8 00 00 00 00 00 fc ff df 48 89 [ 30.632054] Kernel panic - not syncing: Machine halted. [ 30.637386] CPU: 1 PID: 3314 Comm: syzkaller586581 Not tainted 4.4.111-g3301b55 #17 [ 30.645565] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.654916] 0000000000000000 6d35f4bc087fc954 ffff8801db30ce38 ffffffff81d0509d [ 30.662885] ffffffff838367c0 ffff8801db30cf10 ffffffff83808040 ffff880100000000 [ 30.670859] 0000000000000000 ffff8801db30cf00 ffffffff81419a3a 0000000041b58ab3 [ 30.678836] Call Trace: [ 30.681388] <#DF> [] dump_stack+0xc1/0x124 [ 30.687463] [] panic+0x1aa/0x388 [ 30.692453] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 30.699360] [] ? vprintk_emit+0x242/0x850 [ 30.705129] [] ? dump_page_badflags+0x2f/0x250 [ 30.711326] [] ? vprintk_emit+0x242/0x850 [ 30.717091] [] df_debug+0x2d/0x30 [ 30.722170] [] do_double_fault+0x10b/0x210 [ 30.728022] [] double_fault+0x2d/0x40 [ 30.733438] [] ? dump_page_badflags+0x180/0x250 [ 30.739722] [] ? dump_page_badflags+0x1a/0x250 [ 30.745913] <> [ 30.749290] Dumping ftrace buffer: [ 30.753081] (ftrace buffer empty) [ 30.756757] Kernel Offset: disabled [ 30.760348] Rebooting in 86400 seconds..