[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 16.831358] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.746863] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 21.132336] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 21.992875] random: sshd: uninitialized urandom read (32 bytes read, 101 bits of entropy available) [ 22.166515] random: sshd: uninitialized urandom read (32 bytes read, 107 bits of entropy available) Warning: Permanently added '10.128.0.47' (ECDSA) to the list of known hosts. [ 27.566044] random: sshd: uninitialized urandom read (32 bytes read, 115 bits of entropy available) executing program [ 27.671046] ================================================================== [ 27.678457] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 27.685104] Read of size 8 at addr ffff8800b3cbf738 by task syzkaller635907/3332 [ 27.692603] [ 27.694204] CPU: 1 PID: 3332 Comm: syzkaller635907 Not tainted 4.4.111-g1849cd3 #19 [ 27.701965] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.711293] 0000000000000000 dcddf9b98eb655c1 ffff8801d067f850 ffffffff81d0509d [ 27.719285] ffffea0002cf2f80 ffff8800b3cbf738 0000000000000000 ffff8800b3cbf738 [ 27.727267] 0000000000000000 ffff8801d067f888 ffffffff814fd433 ffff8800b3cbf738 [ 27.735249] Call Trace: [ 27.737812] [] dump_stack+0xc1/0x124 [ 27.743150] [] print_address_description+0x73/0x260 [ 27.749784] [] kasan_report+0x285/0x370 [ 27.755378] [] ? __lock_acquire+0x387e/0x4b50 [ 27.761500] [] __asan_report_load8_noabort+0x14/0x20 [ 27.768246] [] __lock_acquire+0x387e/0x4b50 [ 27.774275] [] ? __lock_acquire+0xb5f/0x4b50 [ 27.780303] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.787294] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.794112] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.801097] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.808081] [] lock_acquire+0x15e/0x460 [ 27.813677] [] ? remove_wait_queue+0x14/0x40 [ 27.819718] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 27.826011] [] ? remove_wait_queue+0x14/0x40 [ 27.832048] [] remove_wait_queue+0x14/0x40 [ 27.837911] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 27.844902] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 27.852147] [] ? ep_free+0x1c0/0x1c0 [ 27.857480] [] ep_free+0x93/0x1c0 [ 27.862560] [] ? ep_free+0x1c0/0x1c0 [ 27.867911] [] ep_eventpoll_release+0x44/0x60 [ 27.874025] [] __fput+0x233/0x6d0 [ 27.879099] [] ____fput+0x15/0x20 [ 27.884172] [] task_work_run+0x104/0x180 [ 27.889854] [] do_exit+0x871/0x2a20 [ 27.895115] [] ? handle_mm_fault+0x192d/0x3190 [ 27.901316] [] ? handle_mm_fault+0x3f2/0x3190 [ 27.907431] [] ? release_task+0x1240/0x1240 [ 27.913374] [] do_group_exit+0x108/0x320 [ 27.919056] [] SyS_exit_group+0x1d/0x20 [ 27.924652] [] ? do_group_exit+0x320/0x320 [ 27.930513] [] do_fast_syscall_32+0x314/0x890 [ 27.936641] [] sysenter_flags_fixed+0xd/0x17 [ 27.942668] [ 27.944273] Allocated by task 3332: [ 27.947873] [] save_stack_trace+0x26/0x50 [ 27.953764] [] save_stack+0x43/0xd0 [ 27.959140] [] kasan_kmalloc+0xad/0xe0 [ 27.964775] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 27.971361] [] binder_get_thread+0x181/0x7a0 [ 27.977519] [] binder_poll+0x4a/0x210 [ 27.983074] [] SyS_epoll_ctl+0x10b1/0x2050 [ 27.989055] [] do_fast_syscall_32+0x314/0x890 [ 27.995321] [] sysenter_flags_fixed+0xd/0x17 [ 28.001468] [ 28.003068] Freed by task 3332: [ 28.006319] [] save_stack_trace+0x26/0x50 [ 28.012204] [] save_stack+0x43/0xd0 [ 28.017571] [] kasan_slab_free+0x72/0xc0 [ 28.023369] [] kfree+0xfc/0x300 [ 28.028394] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 28.035162] [] binder_thread_release+0x27d/0x540 [ 28.041673] [] binder_ioctl+0xb94/0x12e0 [ 28.047492] [] compat_SyS_ioctl+0x28a/0x2540 [ 28.053640] [] do_fast_syscall_32+0x314/0x890 [ 28.059882] [] sysenter_flags_fixed+0xd/0x17 [ 28.066029] [ 28.067634] The buggy address belongs to the object at ffff8800b3cbf680 [ 28.067634] which belongs to the cache kmalloc-512 of size 512 [ 28.080270] The buggy address is located 184 bytes inside of [ 28.080270] 512-byte region [ffff8800b3cbf680, ffff8800b3cbf880) [ 28.092121] The buggy address belongs to the page: [ 29.761731] PANIC: double fault, error_code: 0x0 [ 29.766504] CPU: 1 PID: 3332 Comm: syzkaller635907 Not tainted 4.4.111-g1849cd3 #19 [ 29.774266] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.783588] task: ffff8801d1598000 task.stack: ffff8801d0678000 [ 29.789620] RIP: 0010:[] [] dump_page_badflags+0x1a/0x250 [ 29.798466] RSP: 0018:ffff880100000000 EFLAGS: 00010086 [ 29.803884] RAX: ffff8801d1598000 RBX: ffffea0002cf2f80 RCX: ffffffff8148f980 [ 29.811123] RDX: 0000000000000000 RSI: ffffffff838a8360 RDI: ffffea0002cf2f80 [ 29.818370] RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000 [ 29.825612] R10: 0000000000000002 R11: fffffbfff0ad781e R12: 0000000000000000 [ 29.832864] R13: ffffffff838a8360 R14: 0000000000000000 R15: 0000000000000000 [ 29.840109] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 29.848306] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 29.854164] CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670 [ 29.861412] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 29.868660] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 29.875900] Stack: [ 29.878019] [ 29.879614] Call Trace: [ 29.882167] [ 29.884195] 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 [ 29.911094] Kernel panic - not syncing: Machine halted. [ 29.916452] CPU: 1 PID: 3332 Comm: syzkaller635907 Not tainted 4.4.111-g1849cd3 #19 [ 29.924215] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.933539] 0000000000000000 dcddf9b98eb655c1 ffff8801db30ce38 ffffffff81d0509d [ 29.941515] ffffffff838367c0 ffff8801db30cf10 ffffffff83808040 ffff880100000000 [ 29.949501] 0000000000000000 ffff8801db30cf00 ffffffff81419a3a 0000000041b58ab3 [ 29.957468] Call Trace: [ 29.960021] <#DF> [] dump_stack+0xc1/0x124 [ 29.966091] [] panic+0x1aa/0x388 [ 29.971083] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 29.977988] [] ? vprintk_emit+0x242/0x850 [ 29.983756] [] ? dump_page_badflags+0x2f/0x250 [ 29.989973] [] ? vprintk_emit+0x242/0x850 [ 29.995740] [] df_debug+0x2d/0x30 [ 30.000813] [] do_double_fault+0x10b/0x210 [ 30.006669] [] double_fault+0x2d/0x40 [ 30.012100] [] ? dump_page_badflags+0x180/0x250 [ 30.018390] [] ? dump_page_badflags+0x1a/0x250 [ 30.024595] <> [ 30.027992] Dumping ftrace buffer: [ 30.031801] (ftrace buffer empty) [ 30.035490] Kernel Offset: disabled [ 30.039086] Rebooting in 86400 seconds..