[ 36.987758] audit: type=1800 audit(1583166241.802:33): pid=7378 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rc.local" dev="sda1" ino=2465 res=0 [ 37.014790] audit: type=1800 audit(1583166241.802:34): pid=7378 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rmnologin" dev="sda1" ino=2456 res=0 Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 41.186668] random: sshd: uninitialized urandom read (32 bytes read) [ 41.431702] audit: type=1400 audit(1583166246.252:35): avc: denied { map } for pid=7549 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [ 41.483368] random: sshd: uninitialized urandom read (32 bytes read) [ 42.271651] random: sshd: uninitialized urandom read (32 bytes read) [ 46.702860] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.39' (ECDSA) to the list of known hosts. [ 52.309694] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 52.447046] audit: type=1400 audit(1583166257.262:36): avc: denied { map } for pid=7561 comm="syz-executor226" path="/root/syz-executor226024254" dev="sda1" ino=1426 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 52.574555] ================================================================== [ 52.582155] BUG: KASAN: use-after-free in ex_handler_refcount+0x164/0x1a0 [ 52.589086] Write of size 4 at addr ffff88808f782a18 by task kworker/0:2/2827 [ 52.596497] [ 52.598139] CPU: 0 PID: 2827 Comm: kworker/0:2 Not tainted 4.14.172-syzkaller #0 [ 52.605774] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.615138] Workqueue: events do_enable_set [ 52.619467] Call Trace: [ 52.622065] dump_stack+0x13e/0x194 [ 52.625701] ? ex_handler_refcount+0x164/0x1a0 [ 52.630438] print_address_description.cold+0x7c/0x1e2 [ 52.635831] ? ex_handler_refcount+0x164/0x1a0 [ 52.640420] kasan_report.cold+0xa9/0x2ae [ 52.644576] ex_handler_refcount+0x164/0x1a0 [ 52.649108] ? ex_handler_clear_fs+0xb0/0xb0 [ 52.654392] fixup_exception+0x8a/0xc3 [ 52.658287] do_trap+0x72/0x230 [ 52.661575] do_error_trap+0x132/0x2d0 [ 52.665465] ? math_error+0x2d0/0x2d0 [ 52.669271] ? inat_get_avx_attribute+0x5986/0x7953 [ 52.674295] ? __lock_acquire+0x5f7/0x4620 [ 52.678656] ? save_trace+0x290/0x290 [ 52.682457] ? __lock_is_held+0xad/0x140 [ 52.686530] ? save_trace+0x290/0x290 [ 52.690342] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 52.695195] invalid_op+0x1b/0x40 [ 52.698656] RIP: 0010:inat_get_avx_attribute+0x5986/0x7953 [ 52.704281] RSP: 0018:ffff88809e8c7c98 EFLAGS: 00010297 [ 52.709650] RAX: ffff88809e81a000 RBX: ffff88808f782a00 RCX: ffff88808f782a18 [ 52.717036] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88808f782a00 [ 52.724424] RBP: ffff88808f782a00 R08: 0000000000007d6d R09: ffffffff8a09a428 [ 52.731717] R10: ffff88809e81a8a8 R11: ffff88809e81a000 R12: ffff88809e8c7dd8 [ 52.738994] R13: ffff88809ac3b680 R14: ffff88809efdc600 R15: ffff8880aea2acc0 [ 52.746284] ? l2cap_chan_put+0xa/0x30 [ 52.750180] do_enable_set+0x466/0x7f0 [ 52.754068] ? __lock_is_held+0xad/0x140 [ 52.758150] ? lowpan_control_write+0x3f0/0x3f0 [ 52.762838] process_one_work+0x813/0x1540 [ 52.767089] ? pwq_dec_nr_in_flight+0x2b0/0x2b0 [ 52.771769] ? worker_thread+0x15d/0x1070 [ 52.775924] ? _raw_spin_unlock_irq+0x24/0x80 [ 52.780430] worker_thread+0x5d1/0x1070 [ 52.784421] ? process_one_work+0x1540/0x1540 [ 52.788923] kthread+0x30d/0x420 [ 52.792299] ? kthread_create_on_node+0xd0/0xd0 [ 52.796974] ret_from_fork+0x24/0x30 [ 52.800700] [ 52.802326] Allocated by task 2827: [ 52.805955] save_stack+0x32/0xa0 [ 52.809410] kasan_kmalloc+0xbf/0xe0 [ 52.813135] kmem_cache_alloc_trace+0x14d/0x7b0 [ 52.817917] l2cap_chan_create+0x3e/0x3c0 [ 52.822064] chan_create+0xc/0xd0 [ 52.825618] do_enable_set+0x493/0x7f0 [ 52.829523] process_one_work+0x813/0x1540 [ 52.833838] worker_thread+0x5d1/0x1070 [ 52.837818] kthread+0x30d/0x420 [ 52.841303] ret_from_fork+0x24/0x30 [ 52.844997] [ 52.846613] Freed by task 2818: [ 52.850023] save_stack+0x32/0xa0 [ 52.853475] kasan_slab_free+0x75/0xc0 [ 52.857361] kfree+0xcb/0x260 [ 52.860471] l2cap_chan_put+0x27/0x30 [ 52.864416] do_enable_set+0x466/0x7f0 [ 52.868307] process_one_work+0x813/0x1540 [ 52.872543] worker_thread+0x5d1/0x1070 [ 52.876550] kthread+0x30d/0x420 [ 52.879925] ret_from_fork+0x24/0x30 [ 52.883629] [ 52.885262] The buggy address belongs to the object at ffff88808f782a00 [ 52.885262] which belongs to the cache kmalloc-2048 of size 2048 [ 52.898131] The buggy address is located 24 bytes inside of [ 52.898131] 2048-byte region [ffff88808f782a00, ffff88808f783200) [ 52.910030] The buggy address belongs to the page: [ 52.914964] page:ffffea00023de080 count:1 mapcount:0 mapping:ffff88808f782180 index:0x0 compound_mapcount: 0 [ 52.925032] flags: 0xfffe0000008100(slab|head) [ 52.929624] raw: 00fffe0000008100 ffff88808f782180 0000000000000000 0000000100000003 [ 52.937622] raw: ffffea00023dbba0 ffffea000251a320 ffff88812fe56c40 0000000000000000 [ 52.945816] page dumped because: kasan: bad access detected [ 52.951525] [ 52.953161] Memory state around the buggy address: [ 52.958244] ffff88808f782900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 52.965626] ffff88808f782980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 52.972993] >ffff88808f782a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 52.980359] ^ [ 52.984515] ffff88808f782a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 52.991878] ffff88808f782b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 52.999231] ================================================================== [ 53.006591] Disabling lock debugging due to kernel taint executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 53.024674] Kernel panic - not syncing: panic_on_warn set ... [ 53.024674] [ 53.032084] CPU: 0 PID: 2827 Comm: kworker/0:2 Tainted: G B 4.14.172-syzkaller #0 [ 53.040924] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.050618] Workqueue: events do_enable_set [ 53.054939] Call Trace: [ 53.057599] dump_stack+0x13e/0x194 [ 53.061239] panic+0x1f9/0x42d [ 53.064435] ? add_taint.cold+0x16/0x16 [ 53.069372] ? preempt_schedule_common+0x4a/0xc0 [ 53.074147] ? ex_handler_refcount+0x164/0x1a0 [ 53.078743] ? ___preempt_schedule+0x16/0x18 [ 53.083179] ? ex_handler_refcount+0x164/0x1a0 [ 53.087954] kasan_end_report+0x43/0x49 [ 53.091940] kasan_report.cold+0x12f/0x2ae [ 53.096182] ex_handler_refcount+0x164/0x1a0 [ 53.100594] ? ex_handler_clear_fs+0xb0/0xb0 [ 53.105007] fixup_exception+0x8a/0xc3 [ 53.108901] do_trap+0x72/0x230 [ 53.112177] do_error_trap+0x132/0x2d0 [ 53.116115] ? math_error+0x2d0/0x2d0 [ 53.119930] ? inat_get_avx_attribute+0x5986/0x7953 [ 53.125077] ? __lock_acquire+0x5f7/0x4620 [ 53.129317] ? save_trace+0x290/0x290 [ 53.133114] ? __lock_is_held+0xad/0x140 [ 53.137179] ? save_trace+0x290/0x290 [ 53.140983] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 53.145839] invalid_op+0x1b/0x40 [ 53.149296] RIP: 0010:inat_get_avx_attribute+0x5986/0x7953 [ 53.155149] RSP: 0018:ffff88809e8c7c98 EFLAGS: 00010297 [ 53.160643] RAX: ffff88809e81a000 RBX: ffff88808f782a00 RCX: ffff88808f782a18 [ 53.168206] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88808f782a00 [ 53.175476] RBP: ffff88808f782a00 R08: 0000000000007d6d R09: ffffffff8a09a428 [ 53.182745] R10: ffff88809e81a8a8 R11: ffff88809e81a000 R12: ffff88809e8c7dd8 [ 53.190020] R13: ffff88809ac3b680 R14: ffff88809efdc600 R15: ffff8880aea2acc0 [ 53.197313] ? l2cap_chan_put+0xa/0x30 [ 53.201307] do_enable_set+0x466/0x7f0 [ 53.205217] ? __lock_is_held+0xad/0x140 [ 53.209298] ? lowpan_control_write+0x3f0/0x3f0 [ 53.213979] process_one_work+0x813/0x1540 [ 53.218305] ? pwq_dec_nr_in_flight+0x2b0/0x2b0 [ 53.223104] ? worker_thread+0x15d/0x1070 [ 53.227262] ? _raw_spin_unlock_irq+0x24/0x80 [ 53.231759] worker_thread+0x5d1/0x1070 [ 53.235737] ? process_one_work+0x1540/0x1540 [ 53.240321] kthread+0x30d/0x420 [ 53.243703] ? kthread_create_on_node+0xd0/0xd0 [ 53.248376] ret_from_fork+0x24/0x30 [ 53.253856] Kernel Offset: disabled [ 53.257505] Rebooting in 86400 seconds..