[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 16.999491] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.650297] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available) [ 20.898035] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available) [ 21.751097] random: sshd: uninitialized urandom read (32 bytes read, 82 bits of entropy available) [ 21.923882] random: sshd: uninitialized urandom read (32 bytes read, 86 bits of entropy available) Warning: Permanently added '10.128.0.18' (ECDSA) to the list of known hosts. [ 27.302775] random: sshd: uninitialized urandom read (32 bytes read, 90 bits of entropy available) executing program [ 27.403794] ================================================================== [ 27.411177] BUG: KASAN: use-after-free in __lock_acquire+0x387e/0x4b50 [ 27.417814] Read of size 8 at addr ffff8801d09bf738 by task syzkaller519260/3324 [ 27.425315] [ 27.426944] CPU: 0 PID: 3324 Comm: syzkaller519260 Not tainted 4.4.111-g1849cd3 #19 [ 27.434704] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.444031] 0000000000000000 9e24326d4d1065fb ffff8801d037f850 ffffffff81d0509d [ 27.452013] ffffea0007426f80 ffff8801d09bf738 0000000000000000 ffff8801d09bf738 [ 27.459980] 0000000000000000 ffff8801d037f888 ffffffff814fd433 ffff8801d09bf738 [ 27.467953] Call Trace: [ 27.470514] [] dump_stack+0xc1/0x124 [ 27.475862] [] print_address_description+0x73/0x260 [ 27.482584] [] kasan_report+0x285/0x370 [ 27.488180] [] ? __lock_acquire+0x387e/0x4b50 [ 27.494297] [] __asan_report_load8_noabort+0x14/0x20 [ 27.501020] [] __lock_acquire+0x387e/0x4b50 [ 27.506962] [] ? __lock_acquire+0xb5f/0x4b50 [ 27.513078] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.520065] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.526873] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.533862] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 27.540847] [] lock_acquire+0x15e/0x460 [ 27.546446] [] ? remove_wait_queue+0x14/0x40 [ 27.552475] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 27.558769] [] ? remove_wait_queue+0x14/0x40 [ 27.564799] [] remove_wait_queue+0x14/0x40 [ 27.570655] [] ep_unregister_pollwait.isra.6+0xa8/0x220 [ 27.577639] [] ? ep_unregister_pollwait.isra.6+0x114/0x220 [ 27.584882] [] ? ep_free+0x1c0/0x1c0 [ 27.590221] [] ep_free+0x93/0x1c0 [ 27.595295] [] ? ep_free+0x1c0/0x1c0 [ 27.600626] [] ep_eventpoll_release+0x44/0x60 [ 27.606744] [] __fput+0x233/0x6d0 [ 27.611818] [] ____fput+0x15/0x20 [ 27.616889] [] task_work_run+0x104/0x180 [ 27.622567] [] do_exit+0x871/0x2a20 [ 27.627821] [] ? handle_mm_fault+0x192d/0x3190 [ 27.634030] [] ? handle_mm_fault+0x3f2/0x3190 [ 27.640152] [] ? release_task+0x1240/0x1240 [ 27.646099] [] do_group_exit+0x108/0x320 [ 27.651781] [] SyS_exit_group+0x1d/0x20 [ 27.657375] [] ? do_group_exit+0x320/0x320 [ 27.663235] [] do_fast_syscall_32+0x314/0x890 [ 27.669351] [] sysenter_flags_fixed+0xd/0x17 [ 27.675387] [ 27.676989] Allocated by task 3324: [ 27.680582] [] save_stack_trace+0x26/0x50 [ 27.686483] [] save_stack+0x43/0xd0 [ 27.691851] [] kasan_kmalloc+0xad/0xe0 [ 27.697477] [] kmem_cache_alloc_trace+0x100/0x2b0 [ 27.704058] [] binder_get_thread+0x181/0x7a0 [ 27.710203] [] binder_poll+0x4a/0x210 [ 27.715746] [] SyS_epoll_ctl+0x10b1/0x2050 [ 27.721719] [] do_fast_syscall_32+0x314/0x890 [ 27.727954] [] sysenter_flags_fixed+0xd/0x17 [ 27.734102] [ 27.735698] Freed by task 3324: [ 27.738942] [] save_stack_trace+0x26/0x50 [ 27.744833] [] save_stack+0x43/0xd0 [ 27.750198] [] kasan_slab_free+0x72/0xc0 [ 27.755992] [] kfree+0xfc/0x300 [ 27.761022] [] binder_thread_dec_tmpref+0x1c1/0x250 [ 27.767780] [] binder_thread_release+0x27d/0x540 [ 27.774277] [] binder_ioctl+0xb94/0x12e0 [ 27.780079] [] compat_SyS_ioctl+0x28a/0x2540 [ 27.786231] [] do_fast_syscall_32+0x314/0x890 [ 27.792466] [] sysenter_flags_fixed+0xd/0x17 [ 27.798619] [ 27.800216] The buggy address belongs to the object at ffff8801d09bf680 [ 27.800216] which belongs to the cache kmalloc-512 of size 512 [ 27.812847] The buggy address is located 184 bytes inside of [ 27.812847] 512-byte region [ffff8801d09bf680, ffff8801d09bf880) [ 27.824699] The buggy address belongs to the page: [ 29.403547] PANIC: double fault, error_code: 0x0 [ 29.408317] CPU: 0 PID: 3324 Comm: syzkaller519260 Not tainted 4.4.111-g1849cd3 #19 [ 29.416091] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.425416] task: ffff8801d0824740 task.stack: ffff8801d0378000 [ 29.431442] RIP: 0010:[] [] dump_page_badflags+0x1a/0x250 [ 29.440281] RSP: 0018:ffff880100000000 EFLAGS: 00010086 [ 29.445705] RAX: ffff8801d0824740 RBX: ffffea0007426f80 RCX: ffffffff8148f980 [ 29.452946] RDX: 0000000000000000 RSI: ffffffff838a8360 RDI: ffffea0007426f80 [ 29.460188] RBP: ffff880100000030 R08: 0000000000000001 R09: 0000000000000000 [ 29.467446] R10: 0000000000000002 R11: fffffbfff0ad781e R12: 0000000000000000 [ 29.474688] R13: ffffffff838a8360 R14: 0000000000000000 R15: 0000000000000000 [ 29.481931] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 29.490134] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 29.495999] CR2: ffff8800fffffff8 CR3: 000000000420c000 CR4: 0000000000160670 [ 29.503261] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 29.510509] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 29.517747] Stack: [ 29.519957] [ 29.521551] Call Trace: [ 29.524102] [ 29.526131] 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 [ 29.552997] Kernel panic - not syncing: Machine halted. [ 29.558339] CPU: 0 PID: 3324 Comm: syzkaller519260 Not tainted 4.4.111-g1849cd3 #19 [ 29.566100] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.575424] 0000000000000000 9e24326d4d1065fb ffff8801db20ce38 ffffffff81d0509d [ 29.583414] ffffffff838367c0 ffff8801db20cf10 ffffffff83808040 ffff880100000000 [ 29.591394] 0000000000000000 ffff8801db20cf00 ffffffff81419a3a 0000000041b58ab3 [ 29.599360] Call Trace: [ 29.601912] <#DF> [] dump_stack+0xc1/0x124 [ 29.607983] [] panic+0x1aa/0x388 [ 29.612972] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 29.619873] [] ? vprintk_emit+0x242/0x850 [ 29.625651] [] ? dump_page_badflags+0x2f/0x250 [ 29.631852] [] ? vprintk_emit+0x242/0x850 [ 29.637621] [] df_debug+0x2d/0x30 [ 29.642695] [] do_double_fault+0x10b/0x210 [ 29.648556] [] double_fault+0x2d/0x40 [ 29.653979] [] ? dump_page_badflags+0x180/0x250 [ 29.660273] [] ? dump_page_badflags+0x1a/0x250 [ 29.666472] <> [ 29.669891] Dumping ftrace buffer: [ 29.673706] (ftrace buffer empty) [ 29.677390] Kernel Offset: disabled [ 29.680986] Rebooting in 86400 seconds..