[....] Starting file context mai[ 16.426980] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) ntaining 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: [ 21.147463] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available) [ 21.387333] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available) [ 22.250337] random: sshd: uninitialized urandom read (32 bytes read, 100 bits of entropy available) [ 22.417791] random: sshd: uninitialized urandom read (32 bytes read, 104 bits of entropy available) Warning: Permanently added '10.128.0.35' (ECDSA) to the list of known hosts. [ 27.800792] random: sshd: uninitialized urandom read (32 bytes read, 110 bits of entropy available) executing program [ 27.900319] ================================================================== [ 27.907722] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 27.914359] Read of size 8 at addr ffff8801d09acfb8 by task syzkaller640816/3319 [ 27.921890] [ 27.923513] CPU: 0 PID: 3319 Comm: syzkaller640816 Not tainted 4.4.111-gc2f631b #20 [ 27.931274] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.940603] 0000000000000000 75edb0a6b7fbb835 ffff8801cce6f850 ffffffff81d0513d [ 27.948588] ffffea0007426b00 ffff8801d09acfb8 0000000000000000 ffff8801d09acfb8 [ 27.956559] 0000000000000000 ffff8801cce6f888 ffffffff814fd433 ffff8801d09acfb8 [ 27.964548] Call Trace: [ 27.967108] [] dump_stack+0xc1/0x124 [ 27.972443] [] print_address_description+0x73/0x260 [ 27.979078] [] kasan_report+0x285/0x370 [ 27.984669] [] ? __lock_acquire+0x387e/0x4b50 [ 27.990784] [] __asan_report_load8_noabort+0x14/0x20 [ 27.997504] [] __lock_acquire+0x387e/0x4b50 [ 28.003444] [] ? __lock_acquire+0xb5f/0x4b50 [ 28.009481] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.016463] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.023273] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.030268] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.037251] [] lock_acquire+0x15e/0x460 [ 28.042848] [] ? remove_wait_queue+0x14/0x40 [ 28.048879] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 28.055178] [] ? remove_wait_queue+0x14/0x40 [ 28.061207] [] remove_wait_queue+0x14/0x40 [ 28.067061] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 28.074043] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 28.081288] [] ? ep_free+0x1c0/0x1c0 [ 28.086620] [] ep_free+0x93/0x1c0 [ 28.091692] [] ? ep_free+0x1c0/0x1c0 [ 28.097025] [] ep_eventpoll_release+0x44/0x60 [ 28.103139] [] __fput+0x233/0x6d0 [ 28.108211] [] ____fput+0x15/0x20 [ 28.113296] [] task_work_run+0x104/0x180 [ 28.118979] [] do_exit+0x871/0x2a20 [ 28.124237] [] ? handle_mm_fault+0x192d/0x3190 [ 28.130449] [] ? handle_mm_fault+0x3f2/0x3190 [ 28.136572] [] ? release_task+0x1240/0x1240 [ 28.142523] [] do_group_exit+0x108/0x320 [ 28.148204] [] SyS_exit_group+0x1d/0x20 [ 28.153806] [] ? do_group_exit+0x320/0x320 [ 28.159661] [] do_fast_syscall_32+0x314/0x890 [ 28.165776] [] sysenter_flags_fixed+0xd/0x17 [ 28.171813] [ 28.173411] Allocated by task 3319: [ 28.177013] [] save_stack_trace+0x26/0x50 [ 28.182899] [] save_stack+0x43/0xd0 [ 28.188266] [] kasan_kmalloc+0xad/0xe0 [ 28.193898] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 28.200497] [] binder_get_thread+0x181/0x7a0 [ 28.206655] [] binder_poll+0x4a/0x210 [ 28.212199] [] SyS_epoll_ctl+0x10b1/0x2050 [ 28.218169] [] do_fast_syscall_32+0x314/0x890 [ 28.224401] [] sysenter_flags_fixed+0xd/0x17 [ 28.230546] [ 28.232144] Freed by task 3319: [ 28.235388] [] save_stack_trace+0x26/0x50 [ 28.241274] [] save_stack+0x43/0xd0 [ 28.246638] [] kasan_slab_free+0x72/0xc0 [ 28.252437] [] kfree+0xfc/0x300 [ 28.257451] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 28.264202] [] binder_thread_release+0x27d/0x540 [ 28.270703] [] binder_ioctl+0xb94/0x12e0 [ 28.276502] [] compat_SyS_ioctl+0x28a/0x2540 [ 28.282647] [] do_fast_syscall_32+0x314/0x890 [ 28.288882] [] sysenter_flags_fixed+0xd/0x17 [ 28.295027] [ 28.296628] The buggy address belongs to the object at ffff8801d09acf00 [ 28.296628] which belongs to the cache kmalloc-512 of size 512 [ 28.309253] The buggy address is located 184 bytes inside of [ 28.309253] 512-byte region [ffff8801d09acf00, ffff8801d09ad100) [ 28.321095] The buggy address belongs to the page: [ 29.823100] PANIC: double fault, error_code: 0x0 [ 29.827898] CPU: 0 PID: 3319 Comm: syzkaller640816 Not tainted 4.4.111-gc2f631b #20 [ 29.835662] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.844986] task: ffff8801d175c740 task.stack: ffff8801cce68000 [ 29.851020] RIP: 0010:[] [] dump_page_badflags+0x1a/0x250 [ 29.859873] RSP: 0018:ffff880100000000 EFLAGS: 00010086 [ 29.865292] RAX: ffff8801d175c740 RBX: ffffea0007426b00 RCX: ffffffff8148f980 [ 29.872533] RDX: 0000000000000000 RSI: ffffffff838a8360 RDI: ffffea0007426b00 [ 29.879774] RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000 [ 29.887025] R10: 0000000000000002 R11: fffffbfff0ad781e R12: 0000000000000000 [ 29.894265] R13: ffffffff838a8360 R14: 0000000000000000 R15: 0000000000000000 [ 29.901519] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 29.909714] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 29.915565] CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670 [ 29.922808] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 29.930048] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 29.937288] Stack: [ 29.939406] [ 29.941014] Call Trace: [ 29.943565] [ 29.945603] 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 [ 29.972668] Kernel panic - not syncing: Machine halted. [ 29.978003] CPU: 0 PID: 3319 Comm: syzkaller640816 Not tainted 4.4.111-gc2f631b #20 [ 29.985766] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.995107] 0000000000000000 75edb0a6b7fbb835 ffff8801db20ce38 ffffffff81d0513d [ 30.003135] ffffffff838367c0 ffff8801db20cf10 ffffffff83808040 ffff880100000000 [ 30.011163] 0000000000000000 ffff8801db20cf00 ffffffff81419a3a 0000000041b58ab3 [ 30.019154] Call Trace: [ 30.021706] <#DF> [] dump_stack+0xc1/0x124 [ 30.027778] [] panic+0x1aa/0x388 [ 30.032766] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 30.039663] [] ? vprintk_emit+0x242/0x850 [ 30.045429] [] ? dump_page_badflags+0x2f/0x250 [ 30.051630] [] ? vprintk_emit+0x242/0x850 [ 30.057398] [] df_debug+0x2d/0x30 [ 30.062473] [] do_double_fault+0x10b/0x210 [ 30.068329] [] double_fault+0x2d/0x40 [ 30.073750] [] ? dump_page_badflags+0x180/0x250 [ 30.080036] [] ? dump_page_badflags+0x1a/0x250 [ 30.086231] <> [ 30.089624] Dumping ftrace buffer: [ 30.093445] (ftrace buffer empty) [ 30.097124] Kernel Offset: disabled [ 30.100718] Rebooting in 86400 seconds..