[....] Starting enhanced syslogd: rsyslogd[ 16.857736] audit: type=1400 audit(1520712843.269:5): avc: denied { syslog } for pid=4110 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: [ 19.278056] audit: type=1400 audit(1520712845.689:6): avc: denied { map } for pid=4247 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 '10.128.10.14' (ECDSA) to the list of known hosts. [ 28.625419] audit: type=1400 audit(1520712855.037:7): avc: denied { map } for pid=4262 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 20:14:15 parsed 1 programs 2018/03/10 20:14:15 executed programs: 0 [ 28.887163] audit: type=1400 audit(1520712855.298:8): avc: denied { map } for pid=4262 comm="syz-execprog" path="/root/syzkaller-shm487729910" 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 [ 28.898050] IPVS: ftp: loaded support on port[0] = 21 [ 28.950582] ================================================================== [ 28.958047] BUG: KASAN: use-after-free in ucma_close+0x2d7/0x2f0 [ 28.964172] Read of size 8 at addr ffff8801af87c580 by task syz-executor0/4270 [ 28.971505] [ 28.973111] CPU: 0 PID: 4270 Comm: syz-executor0 Not tainted 4.16.0-rc4+ #258 [ 28.980356] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.989687] Call Trace: [ 28.992259] dump_stack+0x194/0x24d [ 28.995864] ? arch_local_irq_restore+0x53/0x53 [ 29.000605] ? show_regs_print_info+0x18/0x18 [ 29.005078] ? save_stack+0xa3/0xd0 [ 29.008695] ? ucma_close+0x2d7/0x2f0 [ 29.012475] print_address_description+0x73/0x250 [ 29.017294] ? ucma_close+0x2d7/0x2f0 [ 29.021074] kasan_report+0x23c/0x360 [ 29.024860] __asan_report_load8_noabort+0x14/0x20 [ 29.029774] ucma_close+0x2d7/0x2f0 [ 29.033379] ? __might_sleep+0x95/0x190 [ 29.037332] ? ucma_free_ctx+0xd90/0xd90 [ 29.041372] __fput+0x327/0x7e0 [ 29.044634] ? fput+0x140/0x140 [ 29.047889] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.052365] ____fput+0x15/0x20 [ 29.055624] task_work_run+0x199/0x270 [ 29.059509] ? task_work_cancel+0x210/0x210 [ 29.063813] ? _raw_spin_unlock+0x22/0x30 [ 29.067943] ? switch_task_namespaces+0x87/0xc0 [ 29.072595] do_exit+0x9bb/0x1ad0 [ 29.076023] ? ucma_create_id+0x45b/0x620 [ 29.080150] ? mm_update_next_owner+0x930/0x930 [ 29.084796] ? ucma_create_id+0x17b/0x620 [ 29.088923] ? ucma_get_event+0xa90/0xa90 [ 29.093061] ? __might_sleep+0x95/0x190 [ 29.097018] ? kasan_check_write+0x14/0x20 [ 29.101231] ? _copy_from_user+0x99/0x110 [ 29.105360] ? ucma_write+0x11f/0x3d0 [ 29.109136] ? ucma_get_event+0xa90/0xa90 [ 29.113263] ? ucma_resolve_route+0x1a0/0x1a0 [ 29.117758] ? ucma_resolve_route+0x1a0/0x1a0 [ 29.122233] ? __vfs_write+0xf7/0x970 [ 29.126011] ? rcu_note_context_switch+0x710/0x710 [ 29.130921] ? kernel_read+0x120/0x120 [ 29.134787] ? __might_sleep+0x95/0x190 [ 29.138749] ? _cond_resched+0x14/0x30 [ 29.142614] ? __inode_security_revalidate+0xd9/0x130 [ 29.147785] ? avc_policy_seqno+0x9/0x20 [ 29.151831] ? security_file_permission+0x89/0x1e0 [ 29.156748] ? compat_SyS_futex+0x288/0x380 [ 29.161044] ? vfs_write+0x224/0x510 [ 29.164743] do_group_exit+0x149/0x400 [ 29.168611] ? compat_SyS_get_robust_list+0x300/0x300 [ 29.173778] ? SyS_write+0x184/0x220 [ 29.177474] ? __do_page_fault+0x3d6/0xc90 [ 29.181686] ? SyS_exit+0x30/0x30 [ 29.185119] ? SyS_read+0x220/0x220 [ 29.188736] ? do_fast_syscall_32+0x156/0xf9f [ 29.193215] ? do_group_exit+0x400/0x400 [ 29.197255] SyS_exit_group+0x1d/0x20 [ 29.201038] do_fast_syscall_32+0x3ec/0xf9f [ 29.205342] ? do_int80_syscall_32+0x9c0/0x9c0 [ 29.209902] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.214639] ? syscall_return_slowpath+0x2ac/0x550 [ 29.219550] ? prepare_exit_to_usermode+0x350/0x350 [ 29.224562] ? sysret32_from_system_call+0x5/0x3c [ 29.229395] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.234223] entry_SYSENTER_compat+0x70/0x7f [ 29.238615] RIP: 0023:0xf7f19c99 [ 29.241953] RSP: 002b:00000000ffe13ccc EFLAGS: 00000282 ORIG_RAX: 00000000000000fc [ 29.249643] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 29.256890] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 29.264134] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 29.271379] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 29.278622] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 29.285886] [ 29.287490] Allocated by task 4270: [ 29.291096] save_stack+0x43/0xd0 [ 29.294526] kasan_kmalloc+0xad/0xe0 [ 29.298218] kmem_cache_alloc_trace+0x136/0x740 [ 29.302865] ucma_alloc_ctx+0xce/0x610 [ 29.306729] ucma_create_id+0x205/0x620 [ 29.310682] ucma_write+0x2d6/0x3d0 [ 29.314285] __vfs_write+0xef/0x970 [ 29.317888] vfs_write+0x189/0x510 [ 29.321402] SyS_write+0xef/0x220 [ 29.324830] do_fast_syscall_32+0x3ec/0xf9f [ 29.329127] entry_SYSENTER_compat+0x70/0x7f [ 29.333508] [ 29.335110] Freed by task 4270: [ 29.338366] save_stack+0x43/0xd0 [ 29.341794] __kasan_slab_free+0x11a/0x170 [ 29.346005] kasan_slab_free+0xe/0x10 [ 29.349802] kfree+0xd9/0x260 [ 29.352887] ucma_create_id+0x45b/0x620 [ 29.356840] ucma_write+0x2d6/0x3d0 [ 29.360441] __vfs_write+0xef/0x970 [ 29.364039] vfs_write+0x189/0x510 [ 29.367558] SyS_write+0xef/0x220 [ 29.370988] do_fast_syscall_32+0x3ec/0xf9f [ 29.375284] entry_SYSENTER_compat+0x70/0x7f [ 29.379664] [ 29.381273] The buggy address belongs to the object at ffff8801af87c500 [ 29.381273] which belongs to the cache kmalloc-256 of size 256 [ 29.393904] The buggy address is located 128 bytes inside of [ 29.393904] 256-byte region [ffff8801af87c500, ffff8801af87c600) [ 29.405754] The buggy address belongs to the page: [ 29.410661] page:ffffea0006be1f00 count:1 mapcount:0 mapping:ffff8801af87c000 index:0xffff8801af87cdc0 [ 29.420168] flags: 0x2fffc0000000100(slab) [ 29.424384] raw: 02fffc0000000100 ffff8801af87c000 ffff8801af87cdc0 0000000100000005 [ 29.432251] raw: ffffea0006beb6e0 ffffea0006b7f220 ffff8801dac007c0 0000000000000000 [ 29.440109] page dumped because: kasan: bad access detected [ 29.445795] [ 29.447397] Memory state around the buggy address: [ 29.452301] ffff8801af87c480: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 29.459636] ffff8801af87c500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.466983] >ffff8801af87c580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.474315] ^ [ 29.477657] ffff8801af87c600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 29.484991] ffff8801af87c680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.492320] ================================================================== [ 29.499648] Disabling lock debugging due to kernel taint [ 29.505147] Kernel panic - not syncing: panic_on_warn set ... [ 29.505147] [ 29.512492] CPU: 0 PID: 4270 Comm: syz-executor0 Tainted: G B 4.16.0-rc4+ #258 [ 29.521038] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.530364] Call Trace: [ 29.532936] dump_stack+0x194/0x24d [ 29.536541] ? arch_local_irq_restore+0x53/0x53 [ 29.541189] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.545916] ? vsnprintf+0x1ed/0x1900 [ 29.549692] ? ucma_close+0x290/0x2f0 [ 29.553467] panic+0x1e4/0x41c [ 29.556641] ? refcount_error_report+0x214/0x214 [ 29.561369] ? add_taint+0x1c/0x50 [ 29.564883] ? add_taint+0x1c/0x50 [ 29.568398] ? ucma_close+0x2d7/0x2f0 [ 29.572169] kasan_end_report+0x50/0x50 [ 29.576112] kasan_report+0x149/0x360 [ 29.579885] __asan_report_load8_noabort+0x14/0x20 [ 29.584787] ucma_close+0x2d7/0x2f0 [ 29.588386] ? __might_sleep+0x95/0x190 [ 29.592333] ? ucma_free_ctx+0xd90/0xd90 [ 29.596366] __fput+0x327/0x7e0 [ 29.599626] ? fput+0x140/0x140 [ 29.602881] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.607349] ____fput+0x15/0x20 [ 29.610603] task_work_run+0x199/0x270 [ 29.614465] ? task_work_cancel+0x210/0x210 [ 29.618762] ? _raw_spin_unlock+0x22/0x30 [ 29.622884] ? switch_task_namespaces+0x87/0xc0 [ 29.627530] do_exit+0x9bb/0x1ad0 [ 29.630956] ? ucma_create_id+0x45b/0x620 [ 29.635082] ? mm_update_next_owner+0x930/0x930 [ 29.639729] ? ucma_create_id+0x17b/0x620 [ 29.643860] ? ucma_get_event+0xa90/0xa90 [ 29.647986] ? __might_sleep+0x95/0x190 [ 29.651935] ? kasan_check_write+0x14/0x20 [ 29.656155] ? _copy_from_user+0x99/0x110 [ 29.660275] ? ucma_write+0x11f/0x3d0 [ 29.664047] ? ucma_get_event+0xa90/0xa90 [ 29.668166] ? ucma_resolve_route+0x1a0/0x1a0 [ 29.672638] ? ucma_resolve_route+0x1a0/0x1a0 [ 29.677105] ? __vfs_write+0xf7/0x970 [ 29.680880] ? rcu_note_context_switch+0x710/0x710 [ 29.685783] ? kernel_read+0x120/0x120 [ 29.689645] ? __might_sleep+0x95/0x190 [ 29.693596] ? _cond_resched+0x14/0x30 [ 29.697459] ? __inode_security_revalidate+0xd9/0x130 [ 29.702625] ? avc_policy_seqno+0x9/0x20 [ 29.706667] ? security_file_permission+0x89/0x1e0 [ 29.711578] ? compat_SyS_futex+0x288/0x380 [ 29.715872] ? vfs_write+0x224/0x510 [ 29.719579] do_group_exit+0x149/0x400 [ 29.723446] ? compat_SyS_get_robust_list+0x300/0x300 [ 29.728628] ? SyS_write+0x184/0x220 [ 29.732322] ? __do_page_fault+0x3d6/0xc90 [ 29.736532] ? SyS_exit+0x30/0x30 [ 29.739959] ? SyS_read+0x220/0x220 [ 29.743561] ? do_fast_syscall_32+0x156/0xf9f [ 29.748031] ? do_group_exit+0x400/0x400 [ 29.752066] SyS_exit_group+0x1d/0x20 [ 29.755842] do_fast_syscall_32+0x3ec/0xf9f [ 29.760140] ? do_int80_syscall_32+0x9c0/0x9c0 [ 29.764699] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.769431] ? syscall_return_slowpath+0x2ac/0x550 [ 29.774336] ? prepare_exit_to_usermode+0x350/0x350 [ 29.779325] ? sysret32_from_system_call+0x5/0x3c [ 29.784142] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.788961] entry_SYSENTER_compat+0x70/0x7f [ 29.793343] RIP: 0023:0xf7f19c99 [ 29.796681] RSP: 002b:00000000ffe13ccc EFLAGS: 00000282 ORIG_RAX: 00000000000000fc [ 29.804358] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 29.811605] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 29.818851] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 29.826094] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 29.833351] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 29.841011] Dumping ftrace buffer: [ 29.844526] (ftrace buffer empty) [ 29.848208] Kernel Offset: disabled [ 29.851812] Rebooting in 86400 seconds..