[....] Starting enhanced syslogd: rsyslogd[ 15.817416] audit: type=1400 audit(1520678549.211:5): avc: denied { syslog } for pid=3992 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.421418] audit: type=1400 audit(1520678551.815:6): avc: denied { map } for pid=4127 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 Warning: Permanently added '10.128.10.4' (ECDSA) to the list of known hosts. [ 24.729042] audit: type=1400 audit(1520678558.122:7): avc: denied { map } for pid=4141 comm="syz-execprog" path="/root/syz-execprog" dev="sda1" ino=16479 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 2018/03/10 10:42:38 parsed 1 programs 2018/03/10 10:42:38 executed programs: 0 [ 24.977147] audit: type=1400 audit(1520678558.370:8): avc: denied { map } for pid=4141 comm="syz-execprog" path="/root/syzkaller-shm241582569" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1 [ 24.990264] IPVS: ftp: loaded support on port[0] = 21 [ 25.034392] ================================================================== [ 25.041799] BUG: KASAN: use-after-free in ucma_close+0x2d7/0x2f0 [ 25.047916] Read of size 8 at addr ffff8801c0c41b00 by task syz-executor0/4149 [ 25.055246] [ 25.056851] CPU: 0 PID: 4149 Comm: syz-executor0 Not tainted 4.16.0-rc4+ #258 [ 25.064093] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.073425] Call Trace: [ 25.076002] dump_stack+0x194/0x24d [ 25.079604] ? arch_local_irq_restore+0x53/0x53 [ 25.084245] ? show_regs_print_info+0x18/0x18 [ 25.088719] ? save_stack+0xa3/0xd0 [ 25.092332] ? ucma_close+0x2d7/0x2f0 [ 25.096108] print_address_description+0x73/0x250 [ 25.100923] ? ucma_close+0x2d7/0x2f0 [ 25.104698] kasan_report+0x23c/0x360 [ 25.108483] __asan_report_load8_noabort+0x14/0x20 [ 25.113384] ucma_close+0x2d7/0x2f0 [ 25.117021] ? __might_sleep+0x95/0x190 [ 25.120976] ? ucma_free_ctx+0xd90/0xd90 [ 25.125015] __fput+0x327/0x7e0 [ 25.128282] ? fput+0x140/0x140 [ 25.131541] ? _raw_spin_unlock_irq+0x27/0x70 [ 25.136014] ____fput+0x15/0x20 [ 25.139267] task_work_run+0x199/0x270 [ 25.143130] ? task_work_cancel+0x210/0x210 [ 25.147430] ? _raw_spin_unlock+0x22/0x30 [ 25.151551] ? switch_task_namespaces+0x87/0xc0 [ 25.156195] do_exit+0x9bb/0x1ad0 [ 25.159621] ? ucma_create_id+0x45b/0x620 [ 25.163746] ? mm_update_next_owner+0x930/0x930 [ 25.168387] ? ucma_create_id+0x17b/0x620 [ 25.172508] ? ucma_get_event+0xa90/0xa90 [ 25.176648] ? __might_sleep+0x95/0x190 [ 25.180607] ? kasan_check_write+0x14/0x20 [ 25.184814] ? _copy_from_user+0x99/0x110 [ 25.188936] ? ucma_write+0x11f/0x3d0 [ 25.192707] ? ucma_get_event+0xa90/0xa90 [ 25.196829] ? ucma_resolve_route+0x1a0/0x1a0 [ 25.201305] ? ucma_resolve_route+0x1a0/0x1a0 [ 25.205774] ? __vfs_write+0xf7/0x970 [ 25.209549] ? rcu_note_context_switch+0x710/0x710 [ 25.214453] ? kernel_read+0x120/0x120 [ 25.218312] ? __might_sleep+0x95/0x190 [ 25.222264] ? _cond_resched+0x14/0x30 [ 25.226125] ? __inode_security_revalidate+0xd9/0x130 [ 25.231286] ? avc_policy_seqno+0x9/0x20 [ 25.235323] ? security_file_permission+0x89/0x1e0 [ 25.240234] ? compat_SyS_futex+0x288/0x380 [ 25.244528] ? vfs_write+0x224/0x510 [ 25.248220] do_group_exit+0x149/0x400 [ 25.252090] ? compat_SyS_get_robust_list+0x300/0x300 [ 25.257251] ? SyS_write+0x184/0x220 [ 25.260940] ? __do_page_fault+0x3d6/0xc90 [ 25.265163] ? SyS_exit+0x30/0x30 [ 25.268591] ? SyS_read+0x220/0x220 [ 25.272192] ? do_fast_syscall_32+0x156/0xf9f [ 25.276670] ? do_group_exit+0x400/0x400 [ 25.280703] SyS_exit_group+0x1d/0x20 [ 25.284483] do_fast_syscall_32+0x3ec/0xf9f [ 25.288782] ? do_int80_syscall_32+0x9c0/0x9c0 [ 25.293337] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.298070] ? syscall_return_slowpath+0x2ac/0x550 [ 25.302971] ? prepare_exit_to_usermode+0x350/0x350 [ 25.307961] ? sysret32_from_system_call+0x5/0x3c [ 25.312781] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.317604] entry_SYSENTER_compat+0x70/0x7f [ 25.321984] RIP: 0023:0xf7f82c99 [ 25.325318] RSP: 002b:00000000ffb67abc EFLAGS: 00000286 ORIG_RAX: 00000000000000fc [ 25.333172] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 25.340420] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 25.347660] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 25.354901] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 25.362143] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 25.369402] [ 25.371007] Allocated by task 4149: [ 25.374606] save_stack+0x43/0xd0 [ 25.378027] kasan_kmalloc+0xad/0xe0 [ 25.381714] kmem_cache_alloc_trace+0x136/0x740 [ 25.386352] ucma_alloc_ctx+0xce/0x610 [ 25.390213] ucma_create_id+0x205/0x620 [ 25.394166] ucma_write+0x2d6/0x3d0 [ 25.397763] __vfs_write+0xef/0x970 [ 25.401358] vfs_write+0x189/0x510 [ 25.404867] SyS_write+0xef/0x220 [ 25.408297] do_fast_syscall_32+0x3ec/0xf9f [ 25.412590] entry_SYSENTER_compat+0x70/0x7f [ 25.416969] [ 25.418571] Freed by task 4149: [ 25.421835] save_stack+0x43/0xd0 [ 25.425263] __kasan_slab_free+0x11a/0x170 [ 25.429470] kasan_slab_free+0xe/0x10 [ 25.433240] kfree+0xd9/0x260 [ 25.436318] ucma_create_id+0x45b/0x620 [ 25.440262] ucma_write+0x2d6/0x3d0 [ 25.443859] __vfs_write+0xef/0x970 [ 25.447455] vfs_write+0x189/0x510 [ 25.450963] SyS_write+0xef/0x220 [ 25.454386] do_fast_syscall_32+0x3ec/0xf9f [ 25.458684] entry_SYSENTER_compat+0x70/0x7f [ 25.463058] [ 25.464665] The buggy address belongs to the object at ffff8801c0c41a80 [ 25.464665] which belongs to the cache kmalloc-256 of size 256 [ 25.477294] The buggy address is located 128 bytes inside of [ 25.477294] 256-byte region [ffff8801c0c41a80, ffff8801c0c41b80) [ 25.489138] The buggy address belongs to the page: [ 25.494045] page:ffffea0007031040 count:1 mapcount:0 mapping:ffff8801c0c41080 index:0x0 [ 25.502168] flags: 0x2fffc0000000100(slab) [ 25.506376] raw: 02fffc0000000100 ffff8801c0c41080 0000000000000000 000000010000000c [ 25.514239] raw: ffffea0007130160 ffffea0007031420 ffff8801dac007c0 0000000000000000 [ 25.522092] page dumped because: kasan: bad access detected [ 25.527774] [ 25.529372] Memory state around the buggy address: [ 25.534273] ffff8801c0c41a00: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc [ 25.541605] ffff8801c0c41a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.548934] >ffff8801c0c41b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.556261] ^ [ 25.559600] ffff8801c0c41b80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 25.566928] ffff8801c0c41c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.574265] ================================================================== [ 25.581612] Disabling lock debugging due to kernel taint [ 25.587149] Kernel panic - not syncing: panic_on_warn set ... [ 25.587149] [ 25.594515] CPU: 0 PID: 4149 Comm: syz-executor0 Tainted: G B 4.16.0-rc4+ #258 [ 25.603074] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.612413] Call Trace: [ 25.614997] dump_stack+0x194/0x24d [ 25.618601] ? arch_local_irq_restore+0x53/0x53 [ 25.623248] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.627976] ? vsnprintf+0x1ed/0x1900 [ 25.631748] ? ucma_close+0x290/0x2f0 [ 25.635518] panic+0x1e4/0x41c [ 25.638680] ? refcount_error_report+0x214/0x214 [ 25.643408] ? add_taint+0x1c/0x50 [ 25.646918] ? add_taint+0x1c/0x50 [ 25.650427] ? ucma_close+0x2d7/0x2f0 [ 25.654196] kasan_end_report+0x50/0x50 [ 25.658143] kasan_report+0x149/0x360 [ 25.661913] __asan_report_load8_noabort+0x14/0x20 [ 25.666809] ucma_close+0x2d7/0x2f0 [ 25.670405] ? __might_sleep+0x95/0x190 [ 25.674360] ? ucma_free_ctx+0xd90/0xd90 [ 25.678399] __fput+0x327/0x7e0 [ 25.681652] ? fput+0x140/0x140 [ 25.684903] ? _raw_spin_unlock_irq+0x27/0x70 [ 25.689368] ____fput+0x15/0x20 [ 25.692619] task_work_run+0x199/0x270 [ 25.696477] ? task_work_cancel+0x210/0x210 [ 25.700780] ? _raw_spin_unlock+0x22/0x30 [ 25.704903] ? switch_task_namespaces+0x87/0xc0 [ 25.709544] do_exit+0x9bb/0x1ad0 [ 25.712975] ? ucma_create_id+0x45b/0x620 [ 25.717102] ? mm_update_next_owner+0x930/0x930 [ 25.721739] ? ucma_create_id+0x17b/0x620 [ 25.725863] ? ucma_get_event+0xa90/0xa90 [ 25.729985] ? __might_sleep+0x95/0x190 [ 25.733933] ? kasan_check_write+0x14/0x20 [ 25.738139] ? _copy_from_user+0x99/0x110 [ 25.742261] ? ucma_write+0x11f/0x3d0 [ 25.746485] ? ucma_get_event+0xa90/0xa90 [ 25.750609] ? ucma_resolve_route+0x1a0/0x1a0 [ 25.755078] ? ucma_resolve_route+0x1a0/0x1a0 [ 25.759545] ? __vfs_write+0xf7/0x970 [ 25.763319] ? rcu_note_context_switch+0x710/0x710 [ 25.768220] ? kernel_read+0x120/0x120 [ 25.772076] ? __might_sleep+0x95/0x190 [ 25.776027] ? _cond_resched+0x14/0x30 [ 25.779887] ? __inode_security_revalidate+0xd9/0x130 [ 25.785044] ? avc_policy_seqno+0x9/0x20 [ 25.789079] ? security_file_permission+0x89/0x1e0 [ 25.793987] ? compat_SyS_futex+0x288/0x380 [ 25.798276] ? vfs_write+0x224/0x510 [ 25.801962] do_group_exit+0x149/0x400 [ 25.805817] ? compat_SyS_get_robust_list+0x300/0x300 [ 25.810974] ? SyS_write+0x184/0x220 [ 25.814656] ? __do_page_fault+0x3d6/0xc90 [ 25.818858] ? SyS_exit+0x30/0x30 [ 25.822281] ? SyS_read+0x220/0x220 [ 25.825878] ? do_fast_syscall_32+0x156/0xf9f [ 25.830363] ? do_group_exit+0x400/0x400 [ 25.834410] SyS_exit_group+0x1d/0x20 [ 25.838180] do_fast_syscall_32+0x3ec/0xf9f [ 25.842475] ? do_int80_syscall_32+0x9c0/0x9c0 [ 25.847032] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.851765] ? syscall_return_slowpath+0x2ac/0x550 [ 25.856663] ? prepare_exit_to_usermode+0x350/0x350 [ 25.861652] ? sysret32_from_system_call+0x5/0x3c [ 25.866465] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.871282] entry_SYSENTER_compat+0x70/0x7f [ 25.875660] RIP: 0023:0xf7f82c99 [ 25.878995] RSP: 002b:00000000ffb67abc EFLAGS: 00000286 ORIG_RAX: 00000000000000fc [ 25.886680] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 25.893917] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 25.901157] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 25.908397] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 25.915634] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 25.923304] Dumping ftrace buffer: [ 25.926813] (ftrace buffer empty) [ 25.930489] Kernel Offset: disabled [ 25.934095] Rebooting in 86400 seconds..