[....] Starting enhanced syslogd: rsyslogd[ 16.128413] audit: type=1400 audit(1521025138.440:5): avc: denied { syslog } for pid=3954 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: [ 22.707138] audit: type=1400 audit(1521025145.018:6): avc: denied { map } for pid=4094 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 '10.128.0.59' (ECDSA) to the list of known hosts. [ 29.052578] audit: type=1400 audit(1521025151.364:7): avc: denied { map } for pid=4108 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 10:59:11 parsed 1 programs 2018/03/14 10:59:11 executed programs: 0 [ 29.313777] audit: type=1400 audit(1521025151.624:8): avc: denied { map } for pid=4108 comm="syz-execprog" path="/root/syzkaller-shm858472215" 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 [ 29.325550] IPVS: ftp: loaded support on port[0] = 21 [ 29.373097] ================================================================== [ 29.380538] BUG: KASAN: use-after-free in ucma_close+0x2d7/0x2f0 [ 29.386658] Read of size 8 at addr ffff8801ca857a80 by task syz-executor0/4116 [ 29.393996] [ 29.395604] CPU: 0 PID: 4116 Comm: syz-executor0 Not tainted 4.16.0-rc5+ #262 [ 29.402854] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.412177] Call Trace: [ 29.414750] dump_stack+0x194/0x24d [ 29.418352] ? arch_local_irq_restore+0x53/0x53 [ 29.422994] ? show_regs_print_info+0x18/0x18 [ 29.427468] ? save_stack+0xa3/0xd0 [ 29.431071] ? ucma_close+0x2d7/0x2f0 [ 29.434843] print_address_description+0x73/0x250 [ 29.439654] ? ucma_close+0x2d7/0x2f0 [ 29.443429] kasan_report+0x23c/0x360 [ 29.447206] __asan_report_load8_noabort+0x14/0x20 [ 29.452108] ucma_close+0x2d7/0x2f0 [ 29.455705] ? __might_sleep+0x95/0x190 [ 29.459652] ? ucma_free_ctx+0xd90/0xd90 [ 29.463684] __fput+0x327/0x7e0 [ 29.466940] ? fput+0x140/0x140 [ 29.470194] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.474664] ____fput+0x15/0x20 [ 29.477926] task_work_run+0x199/0x270 [ 29.481791] ? task_work_cancel+0x210/0x210 [ 29.486087] ? _raw_spin_unlock+0x22/0x30 [ 29.490205] ? switch_task_namespaces+0x87/0xc0 [ 29.494851] do_exit+0x9bb/0x1ad0 [ 29.498279] ? ucma_create_id+0x45b/0x620 [ 29.502410] ? mm_update_next_owner+0x930/0x930 [ 29.507056] ? ucma_create_id+0x17b/0x620 [ 29.511182] ? ucma_get_event+0xa90/0xa90 [ 29.515313] ? __might_sleep+0x95/0x190 [ 29.519266] ? kasan_check_write+0x14/0x20 [ 29.523483] ? _copy_from_user+0x99/0x110 [ 29.527609] ? ucma_write+0x11f/0x3d0 [ 29.531382] ? ucma_get_event+0xa90/0xa90 [ 29.535501] ? ucma_resolve_route+0x1a0/0x1a0 [ 29.539977] ? ucma_resolve_route+0x1a0/0x1a0 [ 29.544443] ? __vfs_write+0xf7/0x970 [ 29.548216] ? rcu_note_context_switch+0x710/0x710 [ 29.553117] ? kernel_read+0x120/0x120 [ 29.556977] ? __might_sleep+0x95/0x190 [ 29.560927] ? _cond_resched+0x14/0x30 [ 29.564788] ? __inode_security_revalidate+0xd9/0x130 [ 29.569952] ? avc_policy_seqno+0x9/0x20 [ 29.573994] ? security_file_permission+0x89/0x1e0 [ 29.578918] ? compat_SyS_futex+0x288/0x380 [ 29.583210] ? vfs_write+0x224/0x510 [ 29.586903] do_group_exit+0x149/0x400 [ 29.590763] ? compat_SyS_get_robust_list+0x300/0x300 [ 29.595921] ? SyS_write+0x184/0x220 [ 29.599605] ? __do_page_fault+0x3d6/0xc90 [ 29.603810] ? SyS_exit+0x30/0x30 [ 29.607235] ? SyS_read+0x220/0x220 [ 29.610842] ? do_fast_syscall_32+0x156/0xf9f [ 29.615310] ? do_group_exit+0x400/0x400 [ 29.619352] SyS_exit_group+0x1d/0x20 [ 29.623128] do_fast_syscall_32+0x3ec/0xf9f [ 29.627430] ? do_int80_syscall_32+0x9c0/0x9c0 [ 29.631985] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.636720] ? syscall_return_slowpath+0x2ac/0x550 [ 29.641623] ? prepare_exit_to_usermode+0x350/0x350 [ 29.646614] ? sysret32_from_system_call+0x5/0x3c [ 29.651433] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.656254] entry_SYSENTER_compat+0x70/0x7f [ 29.660635] RIP: 0023:0xf7f34c99 [ 29.663969] RSP: 002b:00000000ffb5aa6c EFLAGS: 00000282 ORIG_RAX: 00000000000000fc [ 29.671653] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 29.678896] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 29.686146] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 29.693392] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 29.700638] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 29.707903] [ 29.709502] Allocated by task 4116: [ 29.713111] save_stack+0x43/0xd0 [ 29.716535] kasan_kmalloc+0xad/0xe0 [ 29.720220] kmem_cache_alloc_trace+0x136/0x740 [ 29.724872] ucma_alloc_ctx+0xce/0x610 [ 29.728734] ucma_create_id+0x205/0x620 [ 29.732689] ucma_write+0x2d6/0x3d0 [ 29.736294] __vfs_write+0xef/0x970 [ 29.739896] vfs_write+0x189/0x510 [ 29.743406] SyS_write+0xef/0x220 [ 29.746843] do_fast_syscall_32+0x3ec/0xf9f [ 29.751144] entry_SYSENTER_compat+0x70/0x7f [ 29.755532] [ 29.757134] Freed by task 4116: [ 29.760384] save_stack+0x43/0xd0 [ 29.763808] __kasan_slab_free+0x11a/0x170 [ 29.768019] kasan_slab_free+0xe/0x10 [ 29.771809] kfree+0xd9/0x260 [ 29.774887] ucma_create_id+0x45b/0x620 [ 29.778833] ucma_write+0x2d6/0x3d0 [ 29.782430] __vfs_write+0xef/0x970 [ 29.786034] vfs_write+0x189/0x510 [ 29.789546] SyS_write+0xef/0x220 [ 29.793611] do_fast_syscall_32+0x3ec/0xf9f [ 29.797914] entry_SYSENTER_compat+0x70/0x7f [ 29.802293] [ 29.803893] The buggy address belongs to the object at ffff8801ca857a00 [ 29.803893] which belongs to the cache kmalloc-256 of size 256 [ 29.816530] The buggy address is located 128 bytes inside of [ 29.816530] 256-byte region [ffff8801ca857a00, ffff8801ca857b00) [ 29.828376] The buggy address belongs to the page: [ 29.833297] page:ffffea00072a15c0 count:1 mapcount:0 mapping:ffff8801ca857000 index:0x0 [ 29.841422] flags: 0x2fffc0000000100(slab) [ 29.845632] raw: 02fffc0000000100 ffff8801ca857000 0000000000000000 000000010000000c [ 29.853488] raw: ffffea00072a08e0 ffffea00072a1820 ffff8801dac007c0 0000000000000000 [ 29.861340] page dumped because: kasan: bad access detected [ 29.867034] [ 29.868637] Memory state around the buggy address: [ 29.873552] ffff8801ca857980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 29.880885] ffff8801ca857a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.888215] >ffff8801ca857a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.895543] ^ [ 29.898881] ffff8801ca857b00: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 [ 29.906212] ffff8801ca857b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 29.913542] ================================================================== [ 29.920871] Disabling lock debugging due to kernel taint [ 29.926370] Kernel panic - not syncing: panic_on_warn set ... [ 29.926370] [ 29.933721] CPU: 0 PID: 4116 Comm: syz-executor0 Tainted: G B 4.16.0-rc5+ #262 [ 29.942291] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.951619] Call Trace: [ 29.954183] dump_stack+0x194/0x24d [ 29.957785] ? arch_local_irq_restore+0x53/0x53 [ 29.962444] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.967171] ? vsnprintf+0x1ed/0x1900 [ 29.970945] ? ucma_close+0x1f0/0x2f0 [ 29.974731] panic+0x1e4/0x41c [ 29.977897] ? refcount_error_report+0x214/0x214 [ 29.982634] ? add_taint+0x1c/0x50 [ 29.986148] ? add_taint+0x1c/0x50 [ 29.989669] ? ucma_close+0x2d7/0x2f0 [ 29.993461] kasan_end_report+0x50/0x50 [ 29.997407] kasan_report+0x149/0x360 [ 30.001181] __asan_report_load8_noabort+0x14/0x20 [ 30.006088] ucma_close+0x2d7/0x2f0 [ 30.009690] ? __might_sleep+0x95/0x190 [ 30.013726] ? ucma_free_ctx+0xd90/0xd90 [ 30.017761] __fput+0x327/0x7e0 [ 30.021020] ? fput+0x140/0x140 [ 30.024287] ? _raw_spin_unlock_irq+0x27/0x70 [ 30.028759] ____fput+0x15/0x20 [ 30.032013] task_work_run+0x199/0x270 [ 30.035880] ? task_work_cancel+0x210/0x210 [ 30.040186] ? _raw_spin_unlock+0x22/0x30 [ 30.044316] ? switch_task_namespaces+0x87/0xc0 [ 30.048979] do_exit+0x9bb/0x1ad0 [ 30.052407] ? ucma_create_id+0x45b/0x620 [ 30.056537] ? mm_update_next_owner+0x930/0x930 [ 30.061180] ? ucma_create_id+0x17b/0x620 [ 30.065299] ? ucma_get_event+0xa90/0xa90 [ 30.069430] ? __might_sleep+0x95/0x190 [ 30.073382] ? kasan_check_write+0x14/0x20 [ 30.077592] ? _copy_from_user+0x99/0x110 [ 30.081720] ? ucma_write+0x11f/0x3d0 [ 30.085495] ? ucma_get_event+0xa90/0xa90 [ 30.089617] ? ucma_resolve_route+0x1a0/0x1a0 [ 30.094095] ? ucma_resolve_route+0x1a0/0x1a0 [ 30.098561] ? __vfs_write+0xf7/0x970 [ 30.102335] ? rcu_note_context_switch+0x710/0x710 [ 30.107236] ? kernel_read+0x120/0x120 [ 30.111096] ? __might_sleep+0x95/0x190 [ 30.115046] ? _cond_resched+0x14/0x30 [ 30.118904] ? __inode_security_revalidate+0xd9/0x130 [ 30.124068] ? avc_policy_seqno+0x9/0x20 [ 30.128108] ? security_file_permission+0x89/0x1e0 [ 30.133025] ? compat_SyS_futex+0x288/0x380 [ 30.137322] ? vfs_write+0x224/0x510 [ 30.141026] do_group_exit+0x149/0x400 [ 30.144890] ? compat_SyS_get_robust_list+0x300/0x300 [ 30.150054] ? SyS_write+0x184/0x220 [ 30.153739] ? __do_page_fault+0x3d6/0xc90 [ 30.157954] ? SyS_exit+0x30/0x30 [ 30.161378] ? SyS_read+0x220/0x220 [ 30.164979] ? do_fast_syscall_32+0x156/0xf9f [ 30.169445] ? do_group_exit+0x400/0x400 [ 30.173490] SyS_exit_group+0x1d/0x20 [ 30.177266] do_fast_syscall_32+0x3ec/0xf9f [ 30.181573] ? do_int80_syscall_32+0x9c0/0x9c0 [ 30.186127] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 30.190857] ? syscall_return_slowpath+0x2ac/0x550 [ 30.195758] ? prepare_exit_to_usermode+0x350/0x350 [ 30.200748] ? sysret32_from_system_call+0x5/0x3c [ 30.205563] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.210382] entry_SYSENTER_compat+0x70/0x7f [ 30.214761] RIP: 0023:0xf7f34c99 [ 30.218094] RSP: 002b:00000000ffb5aa6c EFLAGS: 00000282 ORIG_RAX: 00000000000000fc [ 30.225774] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000 [ 30.233022] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 30.240276] RBP: 00000000080a2c25 R08: 0000000000000000 R09: 0000000000000000 [ 30.247517] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 30.254766] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 30.262505] Dumping ftrace buffer: [ 30.266022] (ftrace buffer empty) [ 30.269705] Kernel Offset: disabled [ 30.273305] Rebooting in 86400 seconds..