5l[?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: [ 21.708754] random: sshd: uninitialized urandom read (32 bytes read, 40 bits of entropy available) [ 21.940007] random: sshd: uninitialized urandom read (32 bytes read, 40 bits of entropy available) [ 22.782816] random: sshd: uninitialized urandom read (32 bytes read, 112 bits of entropy available) [ 36.758380] random: sshd: uninitialized urandom read (32 bytes read, 125 bits of entropy available) [ 36.888036] random: nonblocking pool is initialized Warning: Permanently added '10.128.15.201' (ECDSA) to the list of known hosts. executing program [ 42.240308] ================================================================== [ 42.247686] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 42.254323] Read of size 8 at addr ffff8801d28b2338 by task syzkaller952160/3322 [ 42.261849] [ 42.263449] CPU: 0 PID: 3322 Comm: syzkaller952160 Not tainted 4.4.111-g3301b55 #24 [ 42.271208] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.280532] 0000000000000000 257ccb6e9bfead70 ffff8801d0ef78d0 ffffffff81d0509d [ 42.288485] ffffea00074a2c80 ffff8801d28b2338 0000000000000000 ffff8801d28b2338 [ 42.296439] 0000000000000000 ffff8801d0ef7908 ffffffff814fd433 ffff8801d28b2338 [ 42.304411] Call Trace: [ 42.306967] [] dump_stack+0xc1/0x124 [ 42.312299] [] print_address_description+0x73/0x260 [ 42.318940] [] kasan_report+0x285/0x370 [ 42.324532] [] ? __lock_acquire+0x387e/0x4b50 [ 42.330645] [] __asan_report_load8_noabort+0x14/0x20 [ 42.337370] [] __lock_acquire+0x387e/0x4b50 [ 42.343308] [] ? __lock_acquire+0xb5f/0x4b50 [ 42.349333] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 42.356321] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 42.363304] [] ? mark_held_locks+0xaf/0x100 [ 42.369249] [] lock_acquire+0x15e/0x460 [ 42.374849] [] ? remove_wait_queue+0x14/0x40 [ 42.380898] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 42.387189] [] ? remove_wait_queue+0x14/0x40 [ 42.393222] [] remove_wait_queue+0x14/0x40 [ 42.399076] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 42.406058] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 42.413305] [] ? ep_free+0x1c0/0x1c0 [ 42.418639] [] ep_free+0x93/0x1c0 [ 42.423713] [] ? ep_free+0x1c0/0x1c0 [ 42.429055] [] ep_eventpoll_release+0x44/0x60 [ 42.435174] [] __fput+0x233/0x6d0 [ 42.440246] [] ____fput+0x15/0x20 [ 42.445337] [] task_work_run+0x104/0x180 [ 42.451025] [] do_exit+0x871/0x2a20 [ 42.456274] [] ? release_task+0x1240/0x1240 [ 42.462215] [] ? SyS_epoll_create+0x190/0x190 [ 42.468335] [] do_group_exit+0x108/0x320 [ 42.474022] [] ? lockdep_sys_exit_thunk+0x12/0x14 [ 42.480483] [] SyS_exit_group+0x1d/0x20 [ 42.486084] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 42.492976] [ 42.494571] Allocated by task 3322: [ 42.498161] [] save_stack_trace+0x26/0x50 [ 42.504062] [] save_stack+0x43/0xd0 [ 42.509422] [] kasan_kmalloc+0xad/0xe0 [ 42.515040] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 42.521622] [] binder_get_thread+0x181/0x7a0 [ 42.527764] [] binder_poll+0x4a/0x210 [ 42.533301] [] SyS_epoll_ctl+0x10b1/0x2050 [ 42.539280] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 42.545943] [ 42.547542] Freed by task 3322: [ 42.550794] [] save_stack_trace+0x26/0x50 [ 42.556676] [] save_stack+0x43/0xd0 [ 42.562041] [] kasan_slab_free+0x72/0xc0 [ 42.567844] [] kfree+0xfc/0x300 [ 42.572861] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 42.579614] [] binder_thread_release+0x27d/0x540 [ 42.586116] [] binder_ioctl+0xb94/0x12e0 [ 42.591909] [] do_vfs_ioctl+0x7aa/0xee0 [ 42.597628] [] SyS_ioctl+0x8f/0xc0 [ 42.602899] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 42.609564] [ 42.611159] The buggy address belongs to the object at ffff8801d28b2280 [ 42.611159] which belongs to the cache kmalloc-512 of size 512 [ 42.623792] The buggy address is located 184 bytes inside of [ 42.623792] 512-byte region [ffff8801d28b2280, ffff8801d28b2480) [ 42.635635] The buggy address belongs to the page: [ 44.197425] PANIC: double fault, error_code: 0x0 [ 44.202190] CPU: 0 PID: 3322 Comm: syzkaller952160 Not tainted 4.4.111-g3301b55 #24 [ 44.209951] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.219275] task: ffff8801d14c4740 task.stack: ffff8801d0ef0000 [ 44.225298] RIP: 0010:[] [] dump_page_badflags+0x1a/0x250 [ 44.234146] RSP: 0018:ffff880100000000 EFLAGS: 00010086 [ 44.239563] RAX: ffff8801d14c4740 RBX: ffffea00074a2c80 RCX: ffffffff8148f980 [ 44.246802] RDX: 0000000000000000 RSI: ffffffff838a83a0 RDI: ffffea00074a2c80 [ 44.254042] RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000 [ 44.261283] R10: 0000000000000002 R11: fffffbfff0ad781e R12: 0000000000000000 [ 44.268521] R13: ffffffff838a83a0 R14: 0000000000000000 R15: 0000000000000000 [ 44.275762] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 44.283958] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 44.289808] CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670 [ 44.297048] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 44.304286] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 44.311522] Stack: [ 44.313634] [ 44.315226] Call Trace: [ 44.317787] [ 44.319814] 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 [ 44.346427] Kernel panic - not syncing: Machine halted. [ 44.351759] CPU: 0 PID: 3322 Comm: syzkaller952160 Not tainted 4.4.111-g3301b55 #24 [ 44.359520] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.368840] 0000000000000000 257ccb6e9bfead70 ffff8801db20ce38 ffffffff81d0509d [ 44.376807] ffffffff838367c0 ffff8801db20cf10 ffffffff83808040 ffff880100000000 [ 44.384783] 0000000000000000 ffff8801db20cf00 ffffffff81419a3a 0000000041b58ab3 [ 44.392733] Call Trace: [ 44.395279] <#DF> [] dump_stack+0xc1/0x124 [ 44.401345] [] panic+0x1aa/0x388 [ 44.406328] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 44.413229] [] ? vprintk_emit+0x242/0x850 [ 44.418994] [] ? dump_page_badflags+0x2f/0x250 [ 44.425193] [] ? vprintk_emit+0x242/0x850 [ 44.430968] [] df_debug+0x2d/0x30 [ 44.436037] [] do_double_fault+0x10b/0x210 [ 44.441890] [] double_fault+0x2d/0x40 [ 44.447311] [] ? dump_page_badflags+0x180/0x250 [ 44.453597] [] ? dump_page_badflags+0x1a/0x250 [ 44.459802] <> [ 44.462795] Dumping ftrace buffer: [ 44.466590] (ftrace buffer empty) [ 44.470267] Kernel Offset: disabled [ 44.473870] Rebooting in 86400 seconds..