[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 15.745319] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.898273] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 21.258235] random: sshd: uninitialized urandom read (32 bytes read, 38 bits of entropy available) [ 22.070379] random: sshd: uninitialized urandom read (32 bytes read, 101 bits of entropy available) [ 22.252711] random: sshd: uninitialized urandom read (32 bytes read, 108 bits of entropy available) Warning: Permanently added '10.128.15.233' (ECDSA) to the list of known hosts. [ 27.667875] random: sshd: uninitialized urandom read (32 bytes read, 120 bits of entropy available) executing program [ 27.771168] ================================================================== [ 27.778583] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 27.785219] Read of size 8 at addr ffff8800b45de838 by task syzkaller002834/3317 [ 27.792732] [ 27.794333] CPU: 1 PID: 3317 Comm: syzkaller002834 Not tainted 4.4.112-g5f6325b #28 [ 27.802634] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.811963] 0000000000000000 5073e148d94f095c ffff8801d0a678d0 ffffffff81d0579d [ 27.819940] ffffea0002d17780 ffff8800b45de838 0000000000000000 ffff8800b45de838 [ 27.827903] 0000000000000000 ffff8801d0a67908 ffffffff814fd9f3 ffff8800b45de838 [ 27.835871] Call Trace: [ 27.838431] [] dump_stack+0xc1/0x124 [ 27.843790] [] print_address_description+0x73/0x260 [ 27.850424] [] kasan_report+0x285/0x370 [ 27.856022] [] ? __lock_acquire+0x387e/0x4b50 [ 27.862139] [] __asan_report_load8_noabort+0x14/0x20 [ 27.868859] [] __lock_acquire+0x387e/0x4b50 [ 27.874801] [] ? __lock_acquire+0xb5f/0x4b50 [ 27.880827] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.887807] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.894786] [] ? mark_held_locks+0xaf/0x100 [ 27.900726] [] lock_acquire+0x15e/0x460 [ 27.906321] [] ? remove_wait_queue+0x14/0x40 [ 27.912350] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 27.918647] [] ? remove_wait_queue+0x14/0x40 [ 27.924674] [] remove_wait_queue+0x14/0x40 [ 27.930530] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 27.937512] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 27.944752] [] ? ep_free+0x1c0/0x1c0 [ 27.950085] [] ep_free+0x93/0x1c0 [ 27.955155] [] ? ep_free+0x1c0/0x1c0 [ 27.960486] [] ep_eventpoll_release+0x44/0x60 [ 27.966612] [] __fput+0x233/0x6d0 [ 27.971691] [] ____fput+0x15/0x20 [ 27.976763] [] task_work_run+0x104/0x180 [ 27.982443] [] do_exit+0x871/0x2a20 [ 27.987687] [] ? release_task+0x1240/0x1240 [ 27.993627] [] ? SyS_epoll_create+0x190/0x190 [ 27.999740] [] do_group_exit+0x108/0x320 [ 28.005422] [] ? lockdep_sys_exit_thunk+0x12/0x14 [ 28.011898] [] SyS_exit_group+0x1d/0x20 [ 28.017493] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 28.024037] [ 28.025634] Allocated by task 3317: [ 28.029228] [] save_stack_trace+0x26/0x50 [ 28.035125] [] save_stack+0x43/0xd0 [ 28.040492] [] kasan_kmalloc+0xad/0xe0 [ 28.046116] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 28.052693] [] binder_get_thread+0x181/0x7a0 [ 28.058839] [] binder_poll+0x4a/0x210 [ 28.064384] [] SyS_epoll_ctl+0x10b1/0x2050 [ 28.070366] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 28.077050] [ 28.078657] Freed by task 3317: [ 28.081901] [] save_stack_trace+0x26/0x50 [ 28.087782] [] save_stack+0x43/0xd0 [ 28.093147] [] kasan_slab_free+0x72/0xc0 [ 28.098943] [] kfree+0xfc/0x300 [ 28.103958] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 28.110708] [] binder_thread_release+0x27d/0x540 [ 28.117210] [] binder_ioctl+0xb94/0x12e0 [ 28.123006] [] do_vfs_ioctl+0x7aa/0xee0 [ 28.128714] [] SyS_ioctl+0x8f/0xc0 [ 28.133995] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 28.140660] [ 28.142257] The buggy address belongs to the object at ffff8800b45de780 [ 28.142257] which belongs to the cache kmalloc-512 of size 512 [ 28.154885] The buggy address is located 184 bytes inside of [ 28.154885] 512-byte region [ffff8800b45de780, ffff8800b45de980) [ 28.166730] The buggy address belongs to the page: [ 29.556104] PANIC: double fault, error_code: 0x0 [ 29.560891] CPU: 1 PID: 3317 Comm: syzkaller002834 Not tainted 4.4.112-g5f6325b #28 [ 29.568653] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.577977] task: ffff8801d18697c0 task.stack: ffff8801d0a60000 [ 29.584001] RIP: 0010:[] [] dump_page_badflags+0x1a/0x250 [ 29.592842] RSP: 0018:ffff880100000000 EFLAGS: 00010086 [ 29.598270] RAX: ffff8801d18697c0 RBX: ffffea0002d17780 RCX: ffffffff8148ff40 [ 29.605508] RDX: 0000000000000000 RSI: ffffffff838a8620 RDI: ffffea0002d17780 [ 29.612749] RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000 [ 29.620000] R10: 0000000000000002 R11: fffffbfff0ad7a1e R12: 0000000000000000 [ 29.627239] R13: ffffffff838a8620 R14: 0000000000000000 R15: 0000000000000000 [ 29.634481] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 29.642676] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 29.648539] CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670 [ 29.655781] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 29.663023] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 29.670347] Stack: [ 29.672462] [ 29.674056] Call Trace: [ 29.676606] [ 29.678643] 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 11 01 ed ff 48 8d 7b 10 48 b8 00 00 00 00 00 fc ff df 48 89 [ 29.705459] Kernel panic - not syncing: Machine halted. [ 29.710803] CPU: 1 PID: 3317 Comm: syzkaller002834 Not tainted 4.4.112-g5f6325b #28 [ 29.718573] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.727895] 0000000000000000 5073e148d94f095c ffff8801db30ce38 ffffffff81d0579d [ 29.735858] ffffffff83836a60 ffff8801db30cf10 ffffffff83808040 ffff880100000000 [ 29.743827] 0000000000000000 ffff8801db30cf00 ffffffff81419e6a 0000000041b58ab3 [ 29.751804] Call Trace: [ 29.754355] <#DF> [] dump_stack+0xc1/0x124 [ 29.760419] [] panic+0x1aa/0x388 [ 29.765402] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 29.772296] [] ? vprintk_emit+0x242/0x850 [ 29.778061] [] ? dump_page_badflags+0x2f/0x250 [ 29.784261] [] ? vprintk_emit+0x242/0x850 [ 29.790026] [] df_debug+0x2d/0x30 [ 29.795114] [] do_double_fault+0x10b/0x210 [ 29.800975] [] double_fault+0x2d/0x40 [ 29.806409] [] ? dump_page_badflags+0x180/0x250 [ 29.812716] [] ? dump_page_badflags+0x1a/0x250 [ 29.818914] <> [ 29.822181] Dumping ftrace buffer: [ 29.825978] (ftrace buffer empty) [ 29.829668] Kernel Offset: disabled [ 29.833264] Rebooting in 86400 seconds..