[....] Starting enhanced syslogd: rsyslogd[ 16.590493] audit: type=1400 audit(1520483059.665:5): avc: denied { syslog } for pid=4087 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: [ 22.726299] audit: type=1400 audit(1520483065.801:6): avc: denied { map } for pid=4228 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 '10.128.0.13' (ECDSA) to the list of known hosts. [ 29.294596] audit: type=1400 audit(1520483072.369:7): avc: denied { map } for pid=4242 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 2018/03/08 04:24:32 parsed 1 programs 2018/03/08 04:24:32 executed programs: 0 [ 29.524769] audit: type=1400 audit(1520483072.599:8): avc: denied { map } for pid=4242 comm="syz-execprog" path="/root/syzkaller-shm077370110" 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 [ 29.534288] IPVS: ftp: loaded support on port[0] = 21 [ 29.582279] ================================================================== [ 29.589732] BUG: KASAN: use-after-free in ucma_close+0x2d7/0x2f0 [ 29.595851] Read of size 8 at addr ffff8801af195240 by task syz-executor0/4250 [ 29.603179] [ 29.604784] CPU: 0 PID: 4250 Comm: syz-executor0 Not tainted 4.16.0-rc4+ #255 [ 29.612027] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.621355] Call Trace: [ 29.623924] dump_stack+0x194/0x24d [ 29.627527] ? arch_local_irq_restore+0x53/0x53 [ 29.632168] ? show_regs_print_info+0x18/0x18 [ 29.636635] ? save_stack+0xa3/0xd0 [ 29.640238] ? ucma_close+0x2d7/0x2f0 [ 29.644012] print_address_description+0x73/0x250 [ 29.648829] ? ucma_close+0x2d7/0x2f0 [ 29.652599] kasan_report+0x23c/0x360 [ 29.656382] __asan_report_load8_noabort+0x14/0x20 [ 29.661289] ucma_close+0x2d7/0x2f0 [ 29.664894] ? __might_sleep+0x95/0x190 [ 29.668842] ? ucma_free_ctx+0xd90/0xd90 [ 29.672875] __fput+0x327/0x7e0 [ 29.676133] ? fput+0x140/0x140 [ 29.679390] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.683866] ____fput+0x15/0x20 [ 29.687122] task_work_run+0x199/0x270 [ 29.690985] ? task_work_cancel+0x210/0x210 [ 29.695280] ? _raw_spin_unlock+0x22/0x30 [ 29.699400] ? switch_task_namespaces+0x87/0xc0 [ 29.704047] do_exit+0x9bb/0x1ad0 [ 29.707470] ? ucma_create_id+0x45b/0x620 [ 29.711595] ? mm_update_next_owner+0x930/0x930 [ 29.716240] ? ucma_create_id+0x17b/0x620 [ 29.720373] ? ucma_get_event+0xa90/0xa90 [ 29.724509] ? __might_sleep+0x95/0x190 [ 29.728462] ? kasan_check_write+0x14/0x20 [ 29.732670] ? _copy_from_user+0x99/0x110 [ 29.736797] ? ucma_write+0x11f/0x3d0 [ 29.740570] ? ucma_get_event+0xa90/0xa90 [ 29.744690] ? ucma_resolve_route+0x1a0/0x1a0 [ 29.749166] ? ucma_resolve_route+0x1a0/0x1a0 [ 29.753633] ? __vfs_write+0xf7/0x970 [ 29.757410] ? rcu_note_context_switch+0x710/0x710 [ 29.762312] ? kernel_read+0x120/0x120 [ 29.766172] ? __might_sleep+0x95/0x190 [ 29.770122] ? _cond_resched+0x14/0x30 [ 29.773981] ? __inode_security_revalidate+0xd9/0x130 [ 29.779147] ? avc_policy_seqno+0x9/0x20 [ 29.783186] ? security_file_permission+0x89/0x1e0 [ 29.788101] ? compat_SyS_futex+0x288/0x380 [ 29.792394] ? vfs_write+0x224/0x510 [ 29.796085] do_group_exit+0x149/0x400 [ 29.799943] ? compat_SyS_get_robust_list+0x300/0x300 [ 29.805106] ? SyS_write+0x184/0x220 [ 29.808794] ? __do_page_fault+0x3d6/0xc90 [ 29.813002] ? SyS_exit+0x30/0x30 [ 29.816430] ? SyS_read+0x220/0x220 [ 29.820034] ? do_fast_syscall_32+0x156/0xf9f [ 29.824502] ? do_group_exit+0x400/0x400 [ 29.828537] SyS_exit_group+0x1d/0x20 [ 29.832312] do_fast_syscall_32+0x3ec/0xf9f [ 29.836611] ? do_int80_syscall_32+0x9c0/0x9c0 [ 29.841166] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.845904] ? syscall_return_slowpath+0x2ac/0x550 [ 29.850806] ? prepare_exit_to_usermode+0x350/0x350 [ 29.855807] ? sysret32_from_system_call+0x5/0x3c [ 29.860626] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.865445] entry_SYSENTER_compat+0x70/0x7f [ 29.869826] RIP: 0023:0xf7fa6c99 [ 29.873160] RSP: 002b:00000000ff9fbf3c EFLAGS: 00000282 ORIG_RAX: 00000000000000fc [ 29.880844] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 29.888085] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 29.895325] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 29.902566] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 29.909808] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 29.917077] [ 29.918677] Allocated by task 4250: [ 29.922277] save_stack+0x43/0xd0 [ 29.925701] kasan_kmalloc+0xad/0xe0 [ 29.929386] kmem_cache_alloc_trace+0x136/0x740 [ 29.934025] ucma_alloc_ctx+0xce/0x610 [ 29.937880] ucma_create_id+0x205/0x620 [ 29.941826] ucma_write+0x2d6/0x3d0 [ 29.945423] __vfs_write+0xef/0x970 [ 29.949018] vfs_write+0x189/0x510 [ 29.952525] SyS_write+0xef/0x220 [ 29.955952] do_fast_syscall_32+0x3ec/0xf9f [ 29.960243] entry_SYSENTER_compat+0x70/0x7f [ 29.964620] [ 29.966215] Freed by task 4250: [ 29.969464] save_stack+0x43/0xd0 [ 29.972885] __kasan_slab_free+0x11a/0x170 [ 29.977093] kasan_slab_free+0xe/0x10 [ 29.980865] kfree+0xd9/0x260 [ 29.983941] ucma_create_id+0x45b/0x620 [ 29.987886] ucma_write+0x2d6/0x3d0 [ 29.991481] __vfs_write+0xef/0x970 [ 29.995075] vfs_write+0x189/0x510 [ 29.998583] SyS_write+0xef/0x220 [ 30.002006] do_fast_syscall_32+0x3ec/0xf9f [ 30.006300] entry_SYSENTER_compat+0x70/0x7f [ 30.010676] [ 30.012275] The buggy address belongs to the object at ffff8801af1951c0 [ 30.012275] which belongs to the cache kmalloc-256 of size 256 [ 30.024901] The buggy address is located 128 bytes inside of [ 30.024901] 256-byte region [ffff8801af1951c0, ffff8801af1952c0) [ 30.036742] The buggy address belongs to the page: [ 30.041643] page:ffffea0006bc6540 count:1 mapcount:0 mapping:ffff8801af195080 index:0xffff8801af195080 [ 30.051063] flags: 0x2fffc0000000100(slab) [ 30.055270] raw: 02fffc0000000100 ffff8801af195080 ffff8801af195080 000000010000000a [ 30.063123] raw: ffffea0006bba2a0 ffffea0006bc67e0 ffff8801dac007c0 0000000000000000 [ 30.070981] page dumped because: kasan: bad access detected [ 30.076660] [ 30.078268] Memory state around the buggy address: [ 30.083170] ffff8801af195100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.090499] ffff8801af195180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 30.097827] >ffff8801af195200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.105155] ^ [ 30.110580] ffff8801af195280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 30.117910] ffff8801af195300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.125237] ================================================================== [ 30.132562] Disabling lock debugging due to kernel taint [ 30.138039] Kernel panic - not syncing: panic_on_warn set ... [ 30.138039] [ 30.145375] CPU: 0 PID: 4250 Comm: syz-executor0 Tainted: G B 4.16.0-rc4+ #255 [ 30.153930] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.163257] Call Trace: [ 30.165820] dump_stack+0x194/0x24d [ 30.169419] ? arch_local_irq_restore+0x53/0x53 [ 30.174058] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 30.178782] ? vsnprintf+0x1ed/0x1900 [ 30.182555] ? ucma_close+0x240/0x2f0 [ 30.186329] panic+0x1e4/0x41c [ 30.189490] ? refcount_error_report+0x214/0x214 [ 30.194217] ? add_taint+0x1c/0x50 [ 30.197728] ? add_taint+0x1c/0x50 [ 30.201249] ? ucma_close+0x2d7/0x2f0 [ 30.205021] kasan_end_report+0x50/0x50 [ 30.208963] kasan_report+0x149/0x360 [ 30.212733] __asan_report_load8_noabort+0x14/0x20 [ 30.217630] ucma_close+0x2d7/0x2f0 [ 30.221230] ? __might_sleep+0x95/0x190 [ 30.225174] ? ucma_free_ctx+0xd90/0xd90 [ 30.229208] __fput+0x327/0x7e0 [ 30.232458] ? fput+0x140/0x140 [ 30.235708] ? _raw_spin_unlock_irq+0x27/0x70 [ 30.240173] ____fput+0x15/0x20 [ 30.243423] task_work_run+0x199/0x270 [ 30.247283] ? task_work_cancel+0x210/0x210 [ 30.251583] ? _raw_spin_unlock+0x22/0x30 [ 30.255701] ? switch_task_namespaces+0x87/0xc0 [ 30.260343] do_exit+0x9bb/0x1ad0 [ 30.263767] ? ucma_create_id+0x45b/0x620 [ 30.267886] ? mm_update_next_owner+0x930/0x930 [ 30.272525] ? ucma_create_id+0x17b/0x620 [ 30.276641] ? ucma_get_event+0xa90/0xa90 [ 30.280770] ? __might_sleep+0x95/0x190 [ 30.284715] ? kasan_check_write+0x14/0x20 [ 30.288921] ? _copy_from_user+0x99/0x110 [ 30.293041] ? ucma_write+0x11f/0x3d0 [ 30.296811] ? ucma_get_event+0xa90/0xa90 [ 30.300931] ? ucma_resolve_route+0x1a0/0x1a0 [ 30.305400] ? ucma_resolve_route+0x1a0/0x1a0 [ 30.309864] ? __vfs_write+0xf7/0x970 [ 30.313635] ? rcu_note_context_switch+0x710/0x710 [ 30.318535] ? kernel_read+0x120/0x120 [ 30.322395] ? __might_sleep+0x95/0x190 [ 30.326342] ? _cond_resched+0x14/0x30 [ 30.330202] ? __inode_security_revalidate+0xd9/0x130 [ 30.335362] ? avc_policy_seqno+0x9/0x20 [ 30.339397] ? security_file_permission+0x89/0x1e0 [ 30.344305] ? compat_SyS_futex+0x288/0x380 [ 30.348607] ? vfs_write+0x224/0x510 [ 30.352300] do_group_exit+0x149/0x400 [ 30.356163] ? compat_SyS_get_robust_list+0x300/0x300 [ 30.361322] ? SyS_write+0x184/0x220 [ 30.365005] ? __do_page_fault+0x3d6/0xc90 [ 30.369210] ? SyS_exit+0x30/0x30 [ 30.372632] ? SyS_read+0x220/0x220 [ 30.376230] ? do_fast_syscall_32+0x156/0xf9f [ 30.380695] ? do_group_exit+0x400/0x400 [ 30.384725] SyS_exit_group+0x1d/0x20 [ 30.388509] do_fast_syscall_32+0x3ec/0xf9f [ 30.392805] ? do_int80_syscall_32+0x9c0/0x9c0 [ 30.397355] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 30.402086] ? syscall_return_slowpath+0x2ac/0x550 [ 30.406987] ? prepare_exit_to_usermode+0x350/0x350 [ 30.411975] ? sysret32_from_system_call+0x5/0x3c [ 30.416791] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.421606] entry_SYSENTER_compat+0x70/0x7f [ 30.425984] RIP: 0023:0xf7fa6c99 [ 30.429319] RSP: 002b:00000000ff9fbf3c EFLAGS: 00000282 ORIG_RAX: 00000000000000fc [ 30.436998] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 30.444238] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 30.451477] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 30.458716] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 30.465958] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 30.473583] Dumping ftrace buffer: [ 30.477108] (ftrace buffer empty) [ 30.480798] Kernel Offset: disabled [ 30.484399] Rebooting in 86400 seconds..