[ 16.258548] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.676866] random: sshd: uninitialized urandom read (32 bytes read, 38 bits of entropy available) [ 22.000597] random: sshd: uninitialized urandom read (32 bytes read, 40 bits of entropy available) [ 22.947260] random: sshd: uninitialized urandom read (32 bytes read, 116 bits of entropy available) [ 23.143093] random: sshd: uninitialized urandom read (32 bytes read, 122 bits of entropy available) [ 27.418821] random: nonblocking pool is initialized Warning: Permanently added '10.128.15.242' (ECDSA) to the list of known hosts. executing program [ 28.621584] ================================================================== [ 28.628988] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 28.635644] Read of size 8 at addr ffff8801d0829c38 by task syzkaller592733/3319 [ 28.643145] [ 28.644751] CPU: 0 PID: 3319 Comm: syzkaller592733 Not tainted 4.4.111-g7902639 #25 [ 28.652514] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.661847] 0000000000000000 15b28841a3f98872 ffff8801d0aef8d0 ffffffff81d0509d [ 28.669822] ffffea0007420a00 ffff8801d0829c38 0000000000000000 ffff8801d0829c38 [ 28.677806] 0000000000000000 ffff8801d0aef908 ffffffff814fd433 ffff8801d0829c38 [ 28.685773] Call Trace: [ 28.688335] [] dump_stack+0xc1/0x124 [ 28.693669] [] print_address_description+0x73/0x260 [ 28.700304] [] kasan_report+0x285/0x370 [ 28.705900] [] ? __lock_acquire+0x387e/0x4b50 [ 28.712016] [] __asan_report_load8_noabort+0x14/0x20 [ 28.718750] [] __lock_acquire+0x387e/0x4b50 [ 28.724691] [] ? __lock_acquire+0xb5f/0x4b50 [ 28.730719] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.737711] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.744700] [] ? mark_held_locks+0xaf/0x100 [ 28.750649] [] lock_acquire+0x15e/0x460 [ 28.756243] [] ? remove_wait_queue+0x14/0x40 [ 28.762370] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 28.768659] [] ? remove_wait_queue+0x14/0x40 [ 28.774696] [] remove_wait_queue+0x14/0x40 [ 28.780553] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 28.787537] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 28.794784] [] ? ep_free+0x1c0/0x1c0 [ 28.800120] [] ep_free+0x93/0x1c0 [ 28.805194] [] ? ep_free+0x1c0/0x1c0 [ 28.810528] [] ep_eventpoll_release+0x44/0x60 [ 28.816654] [] __fput+0x233/0x6d0 [ 28.821737] [] ____fput+0x15/0x20 [ 28.826822] [] task_work_run+0x104/0x180 [ 28.832505] [] do_exit+0x871/0x2a20 [ 28.837752] [] ? release_task+0x1240/0x1240 [ 28.843695] [] ? SyS_epoll_create+0x190/0x190 [ 28.849811] [] do_group_exit+0x108/0x320 [ 28.855491] [] ? lockdep_sys_exit_thunk+0x12/0x14 [ 28.861956] [] SyS_exit_group+0x1d/0x20 [ 28.867549] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 28.874091] [ 28.875693] Allocated by task 3319: [ 28.879284] [] save_stack_trace+0x26/0x50 [ 28.885170] [] save_stack+0x43/0xd0 [ 28.890535] [] kasan_kmalloc+0xad/0xe0 [ 28.896157] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 28.902737] [] binder_get_thread+0x181/0x7a0 [ 28.908889] [] binder_poll+0x4a/0x210 [ 28.914435] [] SyS_epoll_ctl+0x10b1/0x2050 [ 28.920409] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 28.927085] [ 28.928691] Freed by task 3319: [ 28.931935] [] save_stack_trace+0x26/0x50 [ 28.937827] [] save_stack+0x43/0xd0 [ 28.943199] [] kasan_slab_free+0x72/0xc0 [ 28.948996] [] kfree+0xfc/0x300 [ 28.954019] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 28.960771] [] binder_thread_release+0x27d/0x540 [ 28.967268] [] binder_ioctl+0xb94/0x12e0 [ 28.973064] [] do_vfs_ioctl+0x7aa/0xee0 [ 28.978775] [] SyS_ioctl+0x8f/0xc0 [ 28.984049] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 28.990714] [ 28.992313] The buggy address belongs to the object at ffff8801d0829b80 [ 28.992313] which belongs to the cache kmalloc-512 of size 512 [ 29.004935] The buggy address is located 184 bytes inside of [ 29.004935] 512-byte region [ffff8801d0829b80, ffff8801d0829d80) [ 29.016776] The buggy address belongs to the page: [ 30.495292] PANIC: double fault, error_code: 0x0 [ 30.500068] CPU: 0 PID: 3319 Comm: syzkaller592733 Not tainted 4.4.111-g7902639 #25 [ 30.507830] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.517155] task: ffff8800b5342f80 task.stack: ffff8801d0ae8000 [ 30.523178] RIP: 0010:[] [] dump_page_badflags+0x1a/0x250 [ 30.532019] RSP: 0018:ffff880100000000 EFLAGS: 00010086 [ 30.537437] RAX: ffff8800b5342f80 RBX: ffffea0007420a00 RCX: ffffffff8148f980 [ 30.544677] RDX: 0000000000000000 RSI: ffffffff838a8360 RDI: ffffea0007420a00 [ 30.551929] RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000 [ 30.559177] R10: 0000000000000002 R11: fffffbfff0ad781e R12: 0000000000000000 [ 30.566417] R13: ffffffff838a8360 R14: 0000000000000000 R15: 0000000000000000 [ 30.573658] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 30.581866] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 30.587715] CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670 [ 30.594959] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.602210] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.609448] Stack: [ 30.611566] [ 30.613162] Call Trace: [ 30.615712] [ 30.617745] 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 [ 30.644567] Kernel panic - not syncing: Machine halted. [ 30.649901] CPU: 0 PID: 3319 Comm: syzkaller592733 Not tainted 4.4.111-g7902639 #25 [ 30.657663] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.666993] 0000000000000000 15b28841a3f98872 ffff8801db20ce38 ffffffff81d0509d [ 30.674974] ffffffff838367c0 ffff8801db20cf10 ffffffff83808040 ffff880100000000 [ 30.682955] 0000000000000000 ffff8801db20cf00 ffffffff81419a3a 0000000041b58ab3 [ 30.690933] Call Trace: [ 30.693484] <#DF> [] dump_stack+0xc1/0x124 [ 30.699553] [] panic+0x1aa/0x388 [ 30.704540] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 30.711439] [] ? vprintk_emit+0x242/0x850 [ 30.717204] [] ? dump_page_badflags+0x2f/0x250 [ 30.723407] [] ? vprintk_emit+0x242/0x850 [ 30.729192] [] df_debug+0x2d/0x30 [ 30.734266] [] do_double_fault+0x10b/0x210 [ 30.740132] [] double_fault+0x2d/0x40 [ 30.745552] [] ? dump_page_badflags+0x180/0x250 [ 30.751842] [] ? dump_page_badflags+0x1a/0x250 [ 30.758047] <> [ 30.761451] Dumping ftrace buffer: [ 30.765256] (ftrace buffer empty) [ 30.768937] Kernel Offset: disabled [ 30.772537] Rebooting in 86400 seconds..