[ 16.117220] 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: [ 21.287719] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 21.769260] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 22.644769] random: sshd: uninitialized urandom read (32 bytes read, 103 bits of entropy available) [ 22.804966] random: sshd: uninitialized urandom read (32 bytes read, 107 bits of entropy available) Warning: Permanently added '10.128.0.51' (ECDSA) to the list of known hosts. [ 28.177711] random: sshd: uninitialized urandom read (32 bytes read, 115 bits of entropy available) executing program [ 28.277452] ================================================================== [ 28.284857] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 28.291496] Read of size 8 at addr ffff8801d0d619b8 by task syzkaller150974/3314 [ 28.298998] [ 28.300598] CPU: 1 PID: 3314 Comm: syzkaller150974 Not tainted 4.4.112-g3fc4284 #25 [ 28.308366] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.317694] 0000000000000000 a6d224e5348effbf ffff8801d04c7850 ffffffff81d054ed [ 28.325680] ffffea0007435800 ffff8801d0d619b8 0000000000000000 ffff8801d0d619b8 [ 28.333650] 0000000000000000 ffff8801d04c7888 ffffffff814fd953 ffff8801d0d619b8 [ 28.341614] Call Trace: [ 28.344174] [] dump_stack+0xc1/0x124 [ 28.349509] [] print_address_description+0x73/0x260 [ 28.356141] [] kasan_report+0x285/0x370 [ 28.361734] [] ? __lock_acquire+0x387e/0x4b50 [ 28.367867] [] __asan_report_load8_noabort+0x14/0x20 [ 28.374604] [] __lock_acquire+0x387e/0x4b50 [ 28.380550] [] ? __lock_acquire+0xb5f/0x4b50 [ 28.386601] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.393582] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.400392] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.407385] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.414379] [] lock_acquire+0x15e/0x460 [ 28.419983] [] ? remove_wait_queue+0x14/0x40 [ 28.426013] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 28.432307] [] ? remove_wait_queue+0x14/0x40 [ 28.438334] [] remove_wait_queue+0x14/0x40 [ 28.444189] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 28.451179] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 28.458422] [] ? ep_free+0x1c0/0x1c0 [ 28.463768] [] ep_free+0x93/0x1c0 [ 28.468860] [] ? ep_free+0x1c0/0x1c0 [ 28.474193] [] ep_eventpoll_release+0x44/0x60 [ 28.480320] [] __fput+0x233/0x6d0 [ 28.485394] [] ____fput+0x15/0x20 [ 28.490466] [] task_work_run+0x104/0x180 [ 28.496147] [] do_exit+0x871/0x2a20 [ 28.501405] [] ? handle_mm_fault+0x192d/0x3190 [ 28.507607] [] ? handle_mm_fault+0x3f2/0x3190 [ 28.513718] [] ? release_task+0x1240/0x1240 [ 28.519667] [] do_group_exit+0x108/0x320 [ 28.525345] [] SyS_exit_group+0x1d/0x20 [ 28.530937] [] ? do_group_exit+0x320/0x320 [ 28.536792] [] do_fast_syscall_32+0x314/0x890 [ 28.542911] [] sysenter_flags_fixed+0xd/0x17 [ 28.548937] [ 28.550534] Allocated by task 3314: [ 28.554127] [] save_stack_trace+0x26/0x50 [ 28.560011] [] save_stack+0x43/0xd0 [ 28.565385] [] kasan_kmalloc+0xad/0xe0 [ 28.571018] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 28.577596] [] binder_get_thread+0x181/0x7a0 [ 28.583740] [] binder_poll+0x4a/0x210 [ 28.589273] [] SyS_epoll_ctl+0x10b1/0x2050 [ 28.595242] [] do_fast_syscall_32+0x314/0x890 [ 28.601473] [] sysenter_flags_fixed+0xd/0x17 [ 28.607618] [ 28.609214] Freed by task 3314: [ 28.612459] [] save_stack_trace+0x26/0x50 [ 28.618341] [] save_stack+0x43/0xd0 [ 28.623712] [] kasan_slab_free+0x72/0xc0 [ 28.629516] [] kfree+0xfc/0x300 [ 28.634531] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 28.641280] [] binder_thread_release+0x27d/0x540 [ 28.647774] [] binder_ioctl+0xb94/0x12e0 [ 28.653576] [] compat_SyS_ioctl+0x28a/0x2540 [ 28.659722] [] do_fast_syscall_32+0x314/0x890 [ 28.665953] [] sysenter_flags_fixed+0xd/0x17 [ 28.672112] [ 28.673711] The buggy address belongs to the object at ffff8801d0d61900 [ 28.673711] which belongs to the cache kmalloc-512 of size 512 [ 28.686338] The buggy address is located 184 bytes inside of [ 28.686338] 512-byte region [ffff8801d0d61900, ffff8801d0d61b00) [ 28.698201] The buggy address belongs to the page: [ 29.416960] kasan: CONFIG_KASAN_INLINE enabled [ 29.421427] kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN [ 29.434473] Dumping ftrace buffer: [ 29.437999] (ftrace buffer empty) [ 29.441705] Modules linked in: [ 29.445031] CPU: 0 PID: 1734 Comm: udevd Not tainted 4.4.112-g3fc4284 #25 [ 29.451954] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.461316] task: ffff8801d3acaf80 task.stack: ffff8801d3b60000 [ 29.467373] RIP: 0010:[] [] __inode_permission2+0x139/0x240 [ 29.476603] RSP: 0018:ffff8801d3b67908 EFLAGS: 00010206 [ 29.482059] RAX: dffffc0000000000 RBX: ffff8801cd431f40 RCX: ffffffff8153be94 [ 29.489327] RDX: 0000000000000003 RSI: ffff8801cd431f40 RDI: 0000000000000018 [ 29.496629] RBP: ffff8801d3b67938 R08: 0000000000000001 R09: 0000000000000001 [ 29.503903] R10: 0000000000000000 R11: 1ffff1003a76cec2 R12: ffff8801d9857820 [ 29.511175] R13: 0000000000000001 R14: ffff8801cd431f42 R15: 0000000000000000 [ 29.518453] FS: 00007fa4cc0407a0(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 29.526680] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 29.532563] CR2: 0000556bff451110 CR3: 00000001d3b3a000 CR4: 0000000000160670 [ 29.539840] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 29.547128] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 29.554397] Stack: [ 29.556540] ffff8800bb410840 0000000000000001 ffff8801cd431f40 ffff8801d9857820 [ 29.564601] ffff8801d3b67d40 ffff8800b4561129 ffff8801d3b67968 ffffffff8153c00f [ 29.572654] ffff8801d9857820 0000000000000000 ffff8801cd431f40 ffff8801d3b67d40 [ 29.580709] Call Trace: [ 29.583289] [] inode_permission2+0x2f/0x100 [ 29.589264] [] link_path_walk+0x8a8/0x16e0 [ 29.595152] [] ? walk_component+0xff0/0xff0 [ 29.601277] [] ? __mutex_init+0xca/0x100 [ 29.606990] [] path_openat+0x22d/0x3b60 [ 29.612621] [] ? path_mountpoint+0x830/0x830 [ 29.618683] [] ? getname_flags+0xcb/0x580 [ 29.624490] [] ? getname+0x19/0x20 [ 29.629691] [] ? do_sys_open+0x205/0x4b0 [ 29.635412] [] ? SyS_open+0x2d/0x40 [ 29.640694] [] ? entry_SYSCALL_64_fastpath+0x16/0x92 [ 29.647455] [] ? __mutex_unlock_slowpath+0x208/0x3b0 [ 29.654217] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 29.661238] [] ? __lock_is_held+0xa1/0xf0 [ 29.667041] [] do_filp_open+0x197/0x290 [ 29.672770] [] ? user_path_mountpoint_at+0x40/0x40 [ 29.679356] [] ? _raw_spin_unlock+0x2c/0x50 [ 29.685352] [] ? __alloc_fd+0x1e3/0x500 [ 29.690983] [] do_sys_open+0x343/0x4b0 [ 29.696538] [] ? filp_open+0x70/0x70 [ 29.701907] [] ? SyS_read+0x1b0/0x1b0 [ 29.707368] [] SyS_open+0x2d/0x40 [ 29.712477] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 29.719050] Code: 02 00 0f 85 ff 00 00 00 4d 85 e4 4c 8b 7b 20 74 5a e8 bc 3f e2 ff 49 8d 7f 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 e6 00 00 00 49 8b 47 18 48 85 c0 48 89 45 d0 [ 29.746642] RIP [] __inode_permission2+0x139/0x240 [ 29.753358] RSP [ 29.766466] ---[ end trace ad6734be71ae9af3 ]--- [ 29.771255] Kernel panic - not syncing: Fatal exception [ 30.461772] PANIC: double fault, error_code: 0x0 [ 30.466566] CPU: 1 PID: 3314 Comm: syzkaller150974 Tainted: G D 4.4.112-g3fc4284 #25 [ 30.475548] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.484876] task: ffff8800b50c0000 task.stack: ffff8801d04c0000 [ 30.490905] RIP: 0010:[] [] dump_page_badflags+0x1a/0x250 [ 30.499762] RSP: 0018:ffff880100000000 EFLAGS: 00010086 [ 30.505184] RAX: ffff8800b50c0000 RBX: ffffea0007435800 RCX: ffffffff8148fea0 [ 30.512427] RDX: 0000000000000000 RSI: ffffffff838a8620 RDI: ffffea0007435800 [ 30.519670] RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000 [ 30.526915] R10: 0000000000000002 R11: fffffbfff0ad7a1e R12: 0000000000000000 [ 30.534159] R13: ffffffff838a8620 R14: 0000000000000000 R15: 0000000000000000 [ 30.541405] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 30.549605] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 30.555462] CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670 [ 30.562708] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.569952] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.577194] Stack: [ 30.579318] [ 30.580918] Call Trace: [ 30.583472] [ 30.585507] 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 [ 30.912425] Shutting down cpus with NMI [ 30.916868] Dumping ftrace buffer: [ 30.920383] (ftrace buffer empty) [ 30.924063] Kernel Offset: disabled [ 30.927661] Rebooting in 86400 seconds..