[....] Starting enhanced syslogd: rsyslogd[ 16.262251] audit: type=1400 audit(1521020041.020:5): avc: denied { syslog } for pid=4072 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 OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.116335] audit: type=1400 audit(1521020043.875:6): avc: denied { map } for pid=4211 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 '10.128.0.12' (ECDSA) to the list of known hosts. [ 25.493063] audit: type=1400 audit(1521020050.251:7): avc: denied { map } for pid=4225 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 2018/03/14 09:34:10 parsed 1 programs 2018/03/14 09:34:10 executed programs: 0 [ 25.743544] audit: type=1400 audit(1521020050.501:8): avc: denied { map } for pid=4225 comm="syz-execprog" path="/root/syzkaller-shm630540896" 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 [ 25.755165] IPVS: ftp: loaded support on port[0] = 21 [ 25.800720] ================================================================== [ 25.808130] BUG: KASAN: use-after-free in ucma_close+0x2d7/0x2f0 [ 25.814245] Read of size 8 at addr ffff8801b4701200 by task syz-executor0/4233 [ 25.821571] [ 25.823175] CPU: 0 PID: 4233 Comm: syz-executor0 Not tainted 4.16.0-rc5+ #262 [ 25.830422] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.839745] Call Trace: [ 25.842307] dump_stack+0x194/0x24d [ 25.845909] ? arch_local_irq_restore+0x53/0x53 [ 25.850550] ? show_regs_print_info+0x18/0x18 [ 25.855021] ? save_stack+0xa3/0xd0 [ 25.858632] ? ucma_close+0x2d7/0x2f0 [ 25.862415] print_address_description+0x73/0x250 [ 25.867228] ? ucma_close+0x2d7/0x2f0 [ 25.871005] kasan_report+0x23c/0x360 [ 25.874787] __asan_report_load8_noabort+0x14/0x20 [ 25.879692] ucma_close+0x2d7/0x2f0 [ 25.883295] ? __might_sleep+0x95/0x190 [ 25.887241] ? ucma_free_ctx+0xd90/0xd90 [ 25.891279] __fput+0x327/0x7e0 [ 25.894538] ? fput+0x140/0x140 [ 25.897794] ? _raw_spin_unlock_irq+0x27/0x70 [ 25.902267] ____fput+0x15/0x20 [ 25.905527] task_work_run+0x199/0x270 [ 25.909396] ? task_work_cancel+0x210/0x210 [ 25.913690] ? _raw_spin_unlock+0x22/0x30 [ 25.917825] ? switch_task_namespaces+0x87/0xc0 [ 25.922477] do_exit+0x9bb/0x1ad0 [ 25.925904] ? ucma_create_id+0x45b/0x620 [ 25.930038] ? mm_update_next_owner+0x930/0x930 [ 25.934681] ? ucma_create_id+0x17b/0x620 [ 25.938800] ? ucma_get_event+0xa90/0xa90 [ 25.942930] ? __might_sleep+0x95/0x190 [ 25.946884] ? kasan_check_write+0x14/0x20 [ 25.951095] ? _copy_from_user+0x99/0x110 [ 25.955220] ? ucma_write+0x11f/0x3d0 [ 25.958991] ? ucma_get_event+0xa90/0xa90 [ 25.963116] ? ucma_resolve_route+0x1a0/0x1a0 [ 25.967590] ? ucma_resolve_route+0x1a0/0x1a0 [ 25.972057] ? __vfs_write+0xf7/0x970 [ 25.975830] ? rcu_note_context_switch+0x710/0x710 [ 25.980734] ? kernel_read+0x120/0x120 [ 25.984595] ? __might_sleep+0x95/0x190 [ 25.988552] ? _cond_resched+0x14/0x30 [ 25.992413] ? __inode_security_revalidate+0xd9/0x130 [ 25.997585] ? avc_policy_seqno+0x9/0x20 [ 26.001637] ? security_file_permission+0x89/0x1e0 [ 26.006546] ? compat_SyS_futex+0x288/0x380 [ 26.010837] ? vfs_write+0x224/0x510 [ 26.014531] do_group_exit+0x149/0x400 [ 26.018392] ? compat_SyS_get_robust_list+0x300/0x300 [ 26.023558] ? SyS_write+0x184/0x220 [ 26.027241] ? __do_page_fault+0x3d6/0xc90 [ 26.031457] ? SyS_exit+0x30/0x30 [ 26.034882] ? SyS_read+0x220/0x220 [ 26.038482] ? do_fast_syscall_32+0x156/0xf9f [ 26.042952] ? do_group_exit+0x400/0x400 [ 26.046986] SyS_exit_group+0x1d/0x20 [ 26.050759] do_fast_syscall_32+0x3ec/0xf9f [ 26.055073] ? do_int80_syscall_32+0x9c0/0x9c0 [ 26.059632] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.064365] ? syscall_return_slowpath+0x2ac/0x550 [ 26.069269] ? prepare_exit_to_usermode+0x350/0x350 [ 26.074264] ? sysret32_from_system_call+0x5/0x3c [ 26.079083] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.083906] entry_SYSENTER_compat+0x70/0x7f [ 26.088284] RIP: 0023:0xf7ff8c99 [ 26.091618] RSP: 002b:00000000ffbc9ccc EFLAGS: 00000282 ORIG_RAX: 00000000000000fc [ 26.099296] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 26.106538] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 26.113780] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 26.121026] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 26.128269] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 26.135525] [ 26.137128] Allocated by task 4233: [ 26.140727] save_stack+0x43/0xd0 [ 26.144150] kasan_kmalloc+0xad/0xe0 [ 26.147833] kmem_cache_alloc_trace+0x136/0x740 [ 26.152472] ucma_alloc_ctx+0xce/0x610 [ 26.156330] ucma_create_id+0x205/0x620 [ 26.160277] ucma_write+0x2d6/0x3d0 [ 26.163871] __vfs_write+0xef/0x970 [ 26.167467] vfs_write+0x189/0x510 [ 26.170982] SyS_write+0xef/0x220 [ 26.174411] do_fast_syscall_32+0x3ec/0xf9f [ 26.178703] entry_SYSENTER_compat+0x70/0x7f [ 26.183077] [ 26.184673] Freed by task 4233: [ 26.187922] save_stack+0x43/0xd0 [ 26.191346] __kasan_slab_free+0x11a/0x170 [ 26.195556] kasan_slab_free+0xe/0x10 [ 26.199329] kfree+0xd9/0x260 [ 26.202408] ucma_create_id+0x45b/0x620 [ 26.206354] ucma_write+0x2d6/0x3d0 [ 26.209959] __vfs_write+0xef/0x970 [ 26.213564] vfs_write+0x189/0x510 [ 26.217073] SyS_write+0xef/0x220 [ 26.220502] do_fast_syscall_32+0x3ec/0xf9f [ 26.224797] entry_SYSENTER_compat+0x70/0x7f [ 26.229173] [ 26.230773] The buggy address belongs to the object at ffff8801b4701180 [ 26.230773] which belongs to the cache kmalloc-256 of size 256 [ 26.243398] The buggy address is located 128 bytes inside of [ 26.243398] 256-byte region [ffff8801b4701180, ffff8801b4701280) [ 26.255244] The buggy address belongs to the page: [ 26.260145] page:ffffea0006d1c040 count:1 mapcount:0 mapping:ffff8801b4701040 index:0xffff8801b4701e00 [ 26.269564] flags: 0x2fffc0000000100(slab) [ 26.273785] raw: 02fffc0000000100 ffff8801b4701040 ffff8801b4701e00 000000010000000b [ 26.281636] raw: ffffea0006d106e0 ffffea0006c72720 ffff8801dac007c0 0000000000000000 [ 26.289488] page dumped because: kasan: bad access detected [ 26.295166] [ 26.296764] Memory state around the buggy address: [ 26.301668] ffff8801b4701100: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc [ 26.309002] ffff8801b4701180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.316337] >ffff8801b4701200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.323664] ^ [ 26.327000] ffff8801b4701280: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 26.334736] ffff8801b4701300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.342940] ================================================================== [ 26.350265] Disabling lock debugging due to kernel taint [ 26.355739] Kernel panic - not syncing: panic_on_warn set ... [ 26.355739] [ 26.363085] CPU: 0 PID: 4233 Comm: syz-executor0 Tainted: G B 4.16.0-rc5+ #262 [ 26.371627] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.380948] Call Trace: [ 26.383508] dump_stack+0x194/0x24d [ 26.387104] ? arch_local_irq_restore+0x53/0x53 [ 26.391744] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.396471] ? vsnprintf+0x1ed/0x1900 [ 26.400244] ? ucma_close+0x1f0/0x2f0 [ 26.404019] panic+0x1e4/0x41c [ 26.407183] ? refcount_error_report+0x214/0x214 [ 26.411908] ? add_taint+0x1c/0x50 [ 26.415417] ? add_taint+0x1c/0x50 [ 26.418926] ? ucma_close+0x2d7/0x2f0 [ 26.422695] kasan_end_report+0x50/0x50 [ 26.426636] kasan_report+0x149/0x360 [ 26.430406] __asan_report_load8_noabort+0x14/0x20 [ 26.435301] ucma_close+0x2d7/0x2f0 [ 26.438897] ? __might_sleep+0x95/0x190 [ 26.442840] ? ucma_free_ctx+0xd90/0xd90 [ 26.446872] __fput+0x327/0x7e0 [ 26.450125] ? fput+0x140/0x140 [ 26.453374] ? _raw_spin_unlock_irq+0x27/0x70 [ 26.457842] ____fput+0x15/0x20 [ 26.461092] task_work_run+0x199/0x270 [ 26.464948] ? task_work_cancel+0x210/0x210 [ 26.469244] ? _raw_spin_unlock+0x22/0x30 [ 26.473364] ? switch_task_namespaces+0x87/0xc0 [ 26.478005] do_exit+0x9bb/0x1ad0 [ 26.481436] ? ucma_create_id+0x45b/0x620 [ 26.485557] ? mm_update_next_owner+0x930/0x930 [ 26.490193] ? ucma_create_id+0x17b/0x620 [ 26.494310] ? ucma_get_event+0xa90/0xa90 [ 26.498432] ? __might_sleep+0x95/0x190 [ 26.502380] ? kasan_check_write+0x14/0x20 [ 26.506585] ? _copy_from_user+0x99/0x110 [ 26.510709] ? ucma_write+0x11f/0x3d0 [ 26.514478] ? ucma_get_event+0xa90/0xa90 [ 26.518593] ? ucma_resolve_route+0x1a0/0x1a0 [ 26.523061] ? ucma_resolve_route+0x1a0/0x1a0 [ 26.527525] ? __vfs_write+0xf7/0x970 [ 26.531299] ? rcu_note_context_switch+0x710/0x710 [ 26.536195] ? kernel_read+0x120/0x120 [ 26.540052] ? __might_sleep+0x95/0x190 [ 26.543995] ? _cond_resched+0x14/0x30 [ 26.547857] ? __inode_security_revalidate+0xd9/0x130 [ 26.553022] ? avc_policy_seqno+0x9/0x20 [ 26.557058] ? security_file_permission+0x89/0x1e0 [ 26.561960] ? compat_SyS_futex+0x288/0x380 [ 26.566251] ? vfs_write+0x224/0x510 [ 26.569935] do_group_exit+0x149/0x400 [ 26.573790] ? compat_SyS_get_robust_list+0x300/0x300 [ 26.578946] ? SyS_write+0x184/0x220 [ 26.582638] ? __do_page_fault+0x3d6/0xc90 [ 26.586843] ? SyS_exit+0x30/0x30 [ 26.590263] ? SyS_read+0x220/0x220 [ 26.593861] ? do_fast_syscall_32+0x156/0xf9f [ 26.598324] ? do_group_exit+0x400/0x400 [ 26.602356] SyS_exit_group+0x1d/0x20 [ 26.606129] do_fast_syscall_32+0x3ec/0xf9f [ 26.610431] ? do_int80_syscall_32+0x9c0/0x9c0 [ 26.614983] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.619709] ? syscall_return_slowpath+0x2ac/0x550 [ 26.624609] ? prepare_exit_to_usermode+0x350/0x350 [ 26.629595] ? sysret32_from_system_call+0x5/0x3c [ 26.634416] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.639231] entry_SYSENTER_compat+0x70/0x7f [ 26.643606] RIP: 0023:0xf7ff8c99 [ 26.646946] RSP: 002b:00000000ffbc9ccc EFLAGS: 00000282 ORIG_RAX: 00000000000000fc [ 26.654620] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 26.661857] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 26.669096] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 26.676333] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 26.683574] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 26.691271] Dumping ftrace buffer: [ 26.694782] (ftrace buffer empty) [ 26.698460] Kernel Offset: disabled [ 26.702055] Rebooting in 86400 seconds..