[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 15.905474] 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: [ 22.227620] random: sshd: uninitialized urandom read (32 bytes read, 38 bits of entropy available) [ 22.493408] random: sshd: uninitialized urandom read (32 bytes read, 40 bits of entropy available) [ 23.418782] random: sshd: uninitialized urandom read (32 bytes read, 109 bits of entropy available) [ 34.827625] random: sshd: uninitialized urandom read (32 bytes read, 121 bits of entropy available) Warning: Permanently added '10.128.15.247' (ECDSA) to the list of known hosts. [ 40.202121] random: sshd: uninitialized urandom read (32 bytes read, 128 bits of entropy available) executing program [ 40.317450] ================================================================== [ 40.324845] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0xf9/0x110 [ 40.331829] Read of size 8 at addr ffff8800b51e4140 by task syzkaller681895/3338 [ 40.339329] [ 40.340933] CPU: 1 PID: 3338 Comm: syzkaller681895 Not tainted 4.4.112-g3fc4284 #32 [ 40.348698] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.358021] 0000000000000000 0c97d5196efad1fd ffff8801d01a79f0 ffffffff81d054ed [ 40.366015] ffffea0002d47900 ffff8800b51e4140 0000000000000000 ffff8800b51e4140 [ 40.373991] ffff8800b49ec438 ffff8801d01a7a28 ffffffff814fd953 ffff8800b51e4140 [ 40.381959] Call Trace: [ 40.384520] [] dump_stack+0xc1/0x124 [ 40.389854] [] print_address_description+0x73/0x260 [ 40.396520] [] kasan_report+0x285/0x370 [ 40.402118] [] ? sg_remove_request+0xf9/0x110 [ 40.408841] [] __asan_report_load8_noabort+0x14/0x20 [ 40.415563] [] sg_remove_request+0xf9/0x110 [ 40.421505] [] sg_finish_rem_req+0x295/0x340 [ 40.427539] [] sg_read+0xa21/0x1490 [ 40.432796] [] ? __check_object_size+0x154/0x35b [ 40.439175] [] ? sg_proc_seq_show_debug+0xd30/0xd30 [ 40.445815] [] ? fsnotify+0xee0/0xee0 [ 40.451235] [] ? avc_policy_seqno+0x9/0x20 [ 40.457097] [] do_loop_readv_writev+0x141/0x1e0 [ 40.463395] [] ? security_file_permission+0x89/0x1e0 [ 40.470118] [] ? sg_proc_seq_show_debug+0xd30/0xd30 [ 40.476755] [] ? sg_proc_seq_show_debug+0xd30/0xd30 [ 40.483393] [] do_readv_writev+0x5dd/0x6e0 [ 40.489253] [] ? vfs_write+0x530/0x530 [ 40.494768] [] ? _raw_spin_unlock+0x2c/0x50 [ 40.500710] [] ? do_huge_pmd_anonymous_page+0x3dd/0xa10 [ 40.507695] [] ? handle_mm_fault+0x3f2/0x3190 [ 40.513814] [] vfs_readv+0x78/0xb0 [ 40.519087] [] SyS_readv+0xd9/0x240 [ 40.524339] [] ? rw_copy_check_uvector+0x2d0/0x2d0 [ 40.530890] [] ? trace_hardirqs_on_thunk+0x17/0x19 [ 40.537439] [] entry_SYSCALL_64_fastpath+0x16/0x92 [ 40.543992] [ 40.545592] Allocated by task 0: [ 40.548943] (stack is not available) [ 40.552623] [ 40.554224] Freed by task 0: [ 40.557206] (stack is not available) [ 40.560885] [ 40.562482] The buggy address belongs to the object at ffff8800b51e4100 [ 40.562482] which belongs to the cache fasync_cache of size 96 [ 40.575124] The buggy address is located 64 bytes inside of [ 40.575124] 96-byte region [ffff8800b51e4100, ffff8800b51e4160) [ 40.586792] The buggy address belongs to the page: [ 41.118419] kasan: CONFIG_KASAN_INLINE enabled [ 41.122836] kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN [ 41.135643] Dumping ftrace buffer: [ 41.139150] (ftrace buffer empty) [ 41.142830] Modules linked in: [ 41.146120] CPU: 0 PID: 1 Comm: init Not tainted 4.4.112-g3fc4284 #32 [ 41.152672] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.161994] task: ffff8801da308000 task.stack: ffff8801da310000 [ 41.168026] RIP: 0010:[] [] __lock_acquire+0x61f/0x4b50 [ 41.176695] RSP: 0000:ffff8801da317400 EFLAGS: 00010086 [ 41.182122] RAX: dffffc0000000000 RBX: 838a8740c7c748ff RCX: 0000000000000000 [ 41.189368] RDX: 1ffffffff0291fda RSI: 0000000000000001 RDI: ffffffff8148fed1 [ 41.196617] RBP: ffff8801da317598 R08: 0000000000000001 R09: 0000000000000000 [ 41.203862] R10: 0000000000000001 R11: 1ffff1003b462e92 R12: 0000000000000000 [ 41.211101] R13: ffff8801da308000 R14: ffffffff8148fec9 R15: 0000000000000000 [ 41.218340] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 41.226537] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 41.232387] CR2: 0000000000000000 CR3: 000000000420c000 CR4: 0000000000160670 [ 41.239626] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 41.246877] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 41.254123] Stack: [ 41.256238] ffff8801da308000 ffff8801da308870 0000000000000002 ffff8801da308000 [ 41.264222] 0000000000000000 0000000000000000 ffff8801da3175e0 0000000000000046 [ 41.272214] ffff8801da308870 ffff8801da308848 ffff8801da317510 0000000000000046 [ 41.280213] Call Trace: [ 41.282776] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 41.289764] [] ? __module_text_address+0x13/0x140 [ 41.296232] [] ? is_module_text_address+0x2a/0x50 [ 41.302705] [] ? __kernel_text_address+0x6b/0xa0 [ 41.309081] [] ? print_context_stack+0x48/0xc0 [ 41.315281] [] lock_acquire+0x15e/0x460 [ 41.320872] [] ? __posix_lock_file+0x142/0x1640 [ 41.327171] [] ? dump_page_badflags+0x191/0x250 [ 41.333458] [] _raw_spin_lock+0x36/0x50 [ 41.339059] [] ? __posix_lock_file+0x142/0x1640 [ 41.345345] [] __posix_lock_file+0x142/0x1640 [ 41.351458] [] ? remove_vma+0x11d/0x160 [ 41.357052] [] ? mmput+0xf8/0x2d0 [ 41.362131] [] ? do_exit+0x75b/0x2a20 [ 41.367558] [] ? do_group_exit+0x108/0x320 [ 41.373420] [] ? exit_to_usermode_loop+0x122/0x170 [ 41.379970] [] ? prepare_exit_to_usermode+0xe3/0x100 [ 41.386696] [] ? dump_page_badflags+0x191/0x250 [ 41.392982] [] ? locks_remove_flock+0x2d0/0x2d0 [ 41.399271] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 41.406080] [] vfs_lock_file+0xc1/0xe0 [ 41.411586] [] locks_remove_posix.part.34+0x121/0x1e0 [ 41.418401] [] ? do_lock_file_wait+0x240/0x240 [ 41.424602] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 41.431419] [] ? check_preemption_disabled+0x3b/0x200 [ 41.438238] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 41.445221] [] ? __this_cpu_preempt_check+0x1c/0x20 [ 41.452035] [] ? exit_mmap+0x2ba/0x3a0 [ 41.457551] [] ? dump_page_badflags+0x191/0x250 [ 41.463847] [] ? dump_page_badflags+0x1d9/0x250 [ 41.470136] [] locks_remove_posix+0x9b/0xd0 [ 41.476083] [] filp_close+0xf1/0x150 [ 41.481434] [] put_files_struct+0x15a/0x270 [ 41.487377] [] exit_files+0x83/0xb0 [ 41.492630] [] do_exit+0x842/0x2a20 [ 41.497876] [] ? __lock_is_held+0xa1/0xf0 [ 41.503653] [] ? rcu_read_lock_sched_held+0x103/0x120 [ 41.510464] [] ? kmem_cache_free+0x2a4/0x320 [ 41.516495] [] ? release_task+0x1240/0x1240 [ 41.522435] [] do_group_exit+0x108/0x320 [ 41.528116] [] get_signal+0x565/0x1660 [ 41.533636] [] do_signal+0x8b/0x1d40 [ 41.538978] [] ? spurious_fault+0x370/0x370 [ 41.544920] [] ? setup_sigcontext+0x780/0x780 [ 41.551041] [] ? __lock_is_held+0xa1/0xf0 [ 41.556893] [] ? __bad_area_nosemaphore+0x220/0x420 [ 41.563524] [] ? bad_area+0x53/0x80 [ 41.568787] [] ? exit_to_usermode_loop+0xec/0x170 [ 41.575281] [] exit_to_usermode_loop+0x122/0x170 [ 41.581654] [] prepare_exit_to_usermode+0xe3/0x100 [ 41.588203] [] retint_user+0x8/0x3c [ 41.593445] Code: 00 fc ff df 44 89 e3 49 8d 7c de 08 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b6 37 00 00 49 8b 5c de 08 48 85 db 0f 84 28 fb ff ff ff 83 98 01 00 00 49 8d 85 68 08 00 00 48 89 c2 48 89 44 24 [ 41.620039] RIP [] __lock_acquire+0x61f/0x4b50 [ 41.626401] RSP [ 41.629996] ---[ end trace 8453a54f730ed207 ]--- [ 41.634727] Kernel panic - not syncing: Fatal exception [ 42.045588] PANIC: double fault, error_code: 0x0 [ 42.050354] CPU: 1 PID: 3338 Comm: syzkaller681895 Tainted: G D 4.4.112-g3fc4284 #32 [ 42.059329] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.068652] task: ffff8801d229df00 task.stack: ffff8801d01a0000 [ 42.074677] RIP: 0010:[] [] dump_page_badflags+0x8/0x250 [ 42.083441] RSP: 0018:ffff880100000000 EFLAGS: 00010046 [ 42.088864] RAX: ffff8801d229df00 RBX: ffffea0002d47900 RCX: ffffffff8148fea0 [ 42.096118] RDX: 0000000000000000 RSI: ffffffff838a8620 RDI: ffffea0002d47900 [ 42.103359] RBP: ffff880100000010 R08: 0000000000000001 R09: 0000000000000000 [ 42.110598] R10: 0000000000000002 R11: fffffbfff0ad7a1e R12: 0000000000000000 [ 42.117839] R13: ffffffff838a8620 R14: 0000000000000000 R15: 0000000000000000 [ 42.125079] FS: 0000000001582880(0063) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 42.133273] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 42.139138] CR2: ffff8800fffffff8 CR3: 00000000b4082000 CR4: 0000000000160670 [ 42.146379] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 42.153623] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 42.160868] Stack: [ 42.162990] [ 42.164585] Call Trace: [ 42.167136] [ 42.169163] Code: 00 e9 83 fd ff ff e8 a8 e2 06 00 e9 50 fd ff ff e8 9e 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 e8 11 01 [ 42.714236] Shutting down cpus with NMI [ 42.718637] Dumping ftrace buffer: [ 42.722167] (ftrace buffer empty) [ 42.725844] Kernel Offset: disabled [ 42.729439] Rebooting in 86400 seconds..