[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 26.031567] random: sshd: uninitialized urandom read (32 bytes read) [ 26.294975] audit: type=1400 audit(1543519009.532:6): avc: denied { map } for pid=1762 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 [ 26.341390] random: sshd: uninitialized urandom read (32 bytes read) [ 26.793390] random: sshd: uninitialized urandom read (32 bytes read) [ 37.857175] audit: type=1400 audit(1543519021.092:7): avc: denied { map } for pid=1776 comm="sh" path="/bin/dash" dev="sda1" ino=1473 scontext=system_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [ 57.673264] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.8' (ECDSA) to the list of known hosts. [ 63.414229] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 63.510940] audit: type=1400 audit(1543519046.752:8): avc: denied { map } for pid=1801 comm="syz-executor589" path="/root/syz-executor589902928" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 63.600056] hrtimer: interrupt took 86450 ns 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 [ 90.667651] ================================================================== [ 90.675088] BUG: KASAN: use-after-free in perf_output_read+0xe4d/0xfb0 [ 90.681728] Read of size 8 at addr ffff8881d27cfc78 by task syz-executor589/2137 [ 90.689234] [ 90.690846] CPU: 0 PID: 2137 Comm: syz-executor589 Not tainted 4.14.84+ #13 [ 90.697928] Call Trace: [ 90.700504] dump_stack+0xb9/0x11b [ 90.704027] print_address_description+0x60/0x22b [ 90.708950] kasan_report.cold.6+0x11b/0x2dd [ 90.713338] ? perf_output_read+0xe4d/0xfb0 [ 90.717814] perf_output_read+0xe4d/0xfb0 [ 90.721949] ? perf_event_exit_cpu_context+0x170/0x170 [ 90.727210] ? perf_output_copy+0x150/0x1e0 [ 90.731510] perf_output_sample+0x10dd/0x1780 [ 90.736002] ? __perf_event_header__init_id.isra.35+0x274/0x420 [ 90.742040] ? perf_event__output_id_sample+0x70/0x70 [ 90.747217] ? perf_output_sample+0x1780/0x1780 [ 90.751867] ? lock_acquire+0x10f/0x380 [ 90.755817] ? perf_prepare_sample+0x13c0/0x13c0 [ 90.760561] perf_event_output_forward+0x121/0x230 [ 90.765483] ? perf_prepare_sample+0x13c0/0x13c0 [ 90.770218] ? trace_hardirqs_on_caller+0x381/0x520 [ 90.775219] __perf_event_overflow+0x116/0x320 [ 90.779779] perf_swevent_overflow+0x166/0x1f0 [ 90.784340] perf_swevent_event+0x19c/0x270 [ 90.788641] ___perf_sw_event+0x296/0x480 [ 90.792817] ? __lock_acquire+0x619/0x4320 [ 90.797039] ? perf_pending_event+0xe0/0xe0 [ 90.801340] ? do_wp_page+0x254/0x1880 [ 90.805211] ? trace_hardirqs_on+0x10/0x10 [ 90.809443] ? __handle_mm_fault+0x657/0x23a0 [ 90.813927] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 90.818672] ? vm_insert_page+0x6d0/0x6d0 [ 90.822802] ? retint_kernel+0x2d/0x2d [ 90.826673] ? __do_page_fault+0x485/0xb60 [ 90.830888] ? check_preemption_disabled+0x34/0x1e0 [ 90.835899] ? __perf_sw_event+0x3f/0x70 [ 90.839954] __perf_sw_event+0x3f/0x70 [ 90.843819] __do_page_fault+0x77f/0xb60 [ 90.847862] ? bad_area_access_error+0x330/0x330 [ 90.852608] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 90.857457] page_fault+0x22/0x50 [ 90.860982] RIP: 0010:copy_user_enhanced_fast_string+0x7/0x10 [ 90.866840] RSP: 0018:ffff8881cff97b48 EFLAGS: 00010206 [ 90.872180] RAX: 0000000000000000 RBX: 0000000000001000 RCX: 0000000000000500 [ 90.879425] RDX: 0000000000001000 RSI: ffff8881cfd99b00 RDI: 00000000203f1000 [ 90.886673] RBP: 00000000203f0500 R08: 0000000000000000 R09: 0000000000000040 [ 90.893919] R10: ffffed1039fb33ff R11: ffff8881cfd99fff R12: ffff8881cfd99000 [ 90.901171] R13: 00007ffffffff000 R14: 00000000203f1500 R15: 0000000000001000 [ 90.908477] copyout+0x99/0xc0 [ 90.911667] copy_page_to_iter+0x31d/0xd40 [ 90.915890] pipe_to_user+0xa6/0x160 [ 90.919596] __splice_from_pipe+0x324/0x740 [ 90.923922] ? iter_to_pipe+0x410/0x410 [ 90.927875] vmsplice_to_user+0x1bd/0x1e0 [ 90.932004] ? __splice_from_pipe+0x740/0x740 [ 90.936482] ? perf_event_set_output+0x450/0x450 [ 90.941233] ? lock_downgrade+0x560/0x560 [ 90.945357] ? lock_acquire+0x10f/0x380 [ 90.949314] ? check_preemption_disabled+0x34/0x1e0 [ 90.954451] ? __fget+0x22b/0x3a0 [ 90.957895] SyS_vmsplice+0x12f/0x150 [ 90.961677] ? default_file_splice_write+0x80/0x80 [ 90.966594] do_syscall_64+0x19b/0x4b0 [ 90.970465] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 90.975651] RIP: 0033:0x446529 [ 90.978818] RSP: 002b:00007f52a91feda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000116 [ 90.986502] RAX: ffffffffffffffda RBX: 00000000006dbc58 RCX: 0000000000446529 [ 90.993747] RDX: 0000000000000001 RSI: 0000000020000000 RDI: 0000000000000003 [ 91.001101] RBP: 00000000006dbc50 R08: 0000000000000000 R09: 0000000000000000 [ 91.008351] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc5c [ 91.015605] R13: 0004000000000011 R14: 00007f52a91ff9c0 R15: 00000000006dbd4c [ 91.022860] [ 91.024468] Allocated by task 2134: [ 91.028105] kasan_kmalloc.part.1+0x4f/0xd0 [ 91.032405] __kmalloc+0x153/0x340 [ 91.035925] rb_alloc+0x33/0x460 [ 91.039275] perf_mmap+0xc42/0x1370 [ 91.042896] mmap_region+0x836/0xfb0 [ 91.046592] do_mmap+0x551/0xb80 [ 91.049939] vm_mmap_pgoff+0x180/0x1d0 [ 91.053908] SyS_mmap_pgoff+0xf8/0x1a0 [ 91.057773] do_syscall_64+0x19b/0x4b0 [ 91.061638] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 91.066798] [ 91.068406] Freed by task 0: [ 91.071418] kasan_slab_free+0xac/0x190 [ 91.075365] kfree+0xf5/0x310 [ 91.078447] rcu_process_callbacks+0x54d/0xee0 [ 91.083020] __do_softirq+0x20d/0x9bd [ 91.086789] [ 91.088396] The buggy address belongs to the object at ffff8881d27cfb80 [ 91.088396] which belongs to the cache kmalloc-512 of size 512 [ 91.101025] The buggy address is located 248 bytes inside of [ 91.101025] 512-byte region [ffff8881d27cfb80, ffff8881d27cfd80) [ 91.112876] The buggy address belongs to the page: [ 91.117780] page:ffffea000749f380 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 91.127722] flags: 0x4000000000008100(slab|head) [ 91.132457] raw: 4000000000008100 0000000000000000 0000000000000000 00000001800c000c [ 91.140313] raw: dead000000000100 dead000000000200 ffff8881da802c00 0000000000000000 [ 91.148166] page dumped because: kasan: bad access detected [ 91.153848] [ 91.155453] Memory state around the buggy address: [ 91.160522] ffff8881d27cfb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 91.167999] ffff8881d27cfb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 91.175335] >ffff8881d27cfc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 91.182719] ^ [ 91.189967] ffff8881d27cfc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 91.197419] ffff8881d27cfd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 91.204752] ================================================================== [ 91.212082] Disabling lock debugging due to kernel taint [ 91.217738] Kernel panic - not syncing: panic_on_warn set ... [ 91.217738] [ 91.225100] CPU: 0 PID: 2137 Comm: syz-executor589 Tainted: G B 4.14.84+ #13 [ 91.233386] Call Trace: [ 91.235952] dump_stack+0xb9/0x11b [ 91.239470] panic+0x1bf/0x3a4 [ 91.242662] ? add_taint.cold.4+0x16/0x16 [ 91.246792] kasan_end_report+0x43/0x49 [ 91.250740] kasan_report.cold.6+0x77/0x2dd [ 91.255052] ? perf_output_read+0xe4d/0xfb0 [ 91.259363] perf_output_read+0xe4d/0xfb0 [ 91.263490] ? perf_event_exit_cpu_context+0x170/0x170 [ 91.268746] ? perf_output_copy+0x150/0x1e0 [ 91.273041] perf_output_sample+0x10dd/0x1780 [ 91.277514] ? __perf_event_header__init_id.isra.35+0x274/0x420 [ 91.283547] ? perf_event__output_id_sample+0x70/0x70 [ 91.288926] ? perf_output_sample+0x1780/0x1780 [ 91.293575] ? lock_acquire+0x10f/0x380 [ 91.297536] ? perf_prepare_sample+0x13c0/0x13c0 [ 91.302273] perf_event_output_forward+0x121/0x230 [ 91.307181] ? perf_prepare_sample+0x13c0/0x13c0 [ 91.311933] ? trace_hardirqs_on_caller+0x381/0x520 [ 91.317047] __perf_event_overflow+0x116/0x320 [ 91.321607] perf_swevent_overflow+0x166/0x1f0 [ 91.326178] perf_swevent_event+0x19c/0x270 [ 91.330471] ___perf_sw_event+0x296/0x480 [ 91.334624] ? __lock_acquire+0x619/0x4320 [ 91.338832] ? perf_pending_event+0xe0/0xe0 [ 91.343133] ? do_wp_page+0x254/0x1880 [ 91.347136] ? trace_hardirqs_on+0x10/0x10 [ 91.351362] ? __handle_mm_fault+0x657/0x23a0 [ 91.355832] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 91.360568] ? vm_insert_page+0x6d0/0x6d0 [ 91.364711] ? retint_kernel+0x2d/0x2d [ 91.368573] ? __do_page_fault+0x485/0xb60 [ 91.372791] ? check_preemption_disabled+0x34/0x1e0 [ 91.377782] ? __perf_sw_event+0x3f/0x70 [ 91.382014] __perf_sw_event+0x3f/0x70 [ 91.386060] __do_page_fault+0x77f/0xb60 [ 91.390104] ? bad_area_access_error+0x330/0x330 [ 91.394833] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 91.399781] page_fault+0x22/0x50 [ 91.403216] RIP: 0010:copy_user_enhanced_fast_string+0x7/0x10 [ 91.409071] RSP: 0018:ffff8881cff97b48 EFLAGS: 00010206 [ 91.414429] RAX: 0000000000000000 RBX: 0000000000001000 RCX: 0000000000000500 [ 91.421674] RDX: 0000000000001000 RSI: ffff8881cfd99b00 RDI: 00000000203f1000 [ 91.428936] RBP: 00000000203f0500 R08: 0000000000000000 R09: 0000000000000040 [ 91.436182] R10: ffffed1039fb33ff R11: ffff8881cfd99fff R12: ffff8881cfd99000 [ 91.443428] R13: 00007ffffffff000 R14: 00000000203f1500 R15: 0000000000001000 [ 91.450688] copyout+0x99/0xc0 [ 91.453871] copy_page_to_iter+0x31d/0xd40 [ 91.458084] pipe_to_user+0xa6/0x160 [ 91.461780] __splice_from_pipe+0x324/0x740 [ 91.466079] ? iter_to_pipe+0x410/0x410 [ 91.470028] vmsplice_to_user+0x1bd/0x1e0 [ 91.474149] ? __splice_from_pipe+0x740/0x740 [ 91.478631] ? perf_event_set_output+0x450/0x450 [ 91.483365] ? lock_downgrade+0x560/0x560 [ 91.487483] ? lock_acquire+0x10f/0x380 [ 91.491431] ? check_preemption_disabled+0x34/0x1e0 [ 91.496425] ? __fget+0x22b/0x3a0 [ 91.499857] SyS_vmsplice+0x12f/0x150 [ 91.503633] ? default_file_splice_write+0x80/0x80 [ 91.508535] do_syscall_64+0x19b/0x4b0 [ 91.512400] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 91.517562] RIP: 0033:0x446529 [ 91.520729] RSP: 002b:00007f52a91feda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000116 [ 91.528408] RAX: ffffffffffffffda RBX: 00000000006dbc58 RCX: 0000000000446529 [ 91.535759] RDX: 0000000000000001 RSI: 0000000020000000 RDI: 0000000000000003 [ 91.543049] RBP: 00000000006dbc50 R08: 0000000000000000 R09: 0000000000000000 [ 91.550300] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc5c [ 91.557550] R13: 0004000000000011 R14: 00007f52a91ff9c0 R15: 00000000006dbd4c [ 91.565118] Kernel Offset: 0xc200000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 91.575939] Rebooting in 86400 seconds..