executing program syzkaller login: [ 16.505693] ================================================================== [ 16.506330] BUG: KASAN: use-after-free in tipc_group_self+0x1a2/0x1b0 [ 16.506903] Read of size 4 at addr ffff88003c6e636c by task syzkaller085005/2995 [ 16.507599] [ 16.507707] CPU: 1 PID: 2995 Comm: syzkaller085005 Not tainted 4.14.0-rc5-next-20171018+ #8 [ 16.508233] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 16.508761] Call Trace: [ 16.508931] dump_stack+0x194/0x257 [ 16.509165] ? arch_local_irq_restore+0x53/0x53 [ 16.509462] ? show_regs_print_info+0x65/0x65 [ 16.509753] ? tipc_group_self+0x1a2/0x1b0 [ 16.510025] print_address_description+0x73/0x250 [ 16.510369] ? tipc_group_self+0x1a2/0x1b0 [ 16.510660] kasan_report+0x25b/0x340 [ 16.510900] __asan_report_load4_noabort+0x14/0x20 [ 16.511189] tipc_group_self+0x1a2/0x1b0 [ 16.511429] tipc_sk_leave+0xfc/0x200 [ 16.511654] ? tipc_sk_withdraw+0x6b0/0x6b0 [ 16.511908] ? __local_bh_enable_ip+0x9d/0x160 [ 16.512178] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.512605] ? lock_sock_nested+0x91/0x110 [ 16.513006] ? trace_hardirqs_on+0xd/0x10 [ 16.513400] ? __local_bh_enable_ip+0x9d/0x160 [ 16.513822] tipc_release+0x154/0xfe0 [ 16.514140] ? kernel_text_address+0x102/0x140 [ 16.514589] ? tipc_sk_backlog_rcv+0x370/0x370 [ 16.514989] ? __kernel_text_address+0xd/0x40 [ 16.515354] ? unwind_get_return_address+0x61/0xa0 [ 16.515724] ? __save_stack_trace+0x7e/0xd0 [ 16.516081] ? check_noncircular+0x20/0x20 [ 16.516435] ? check_noncircular+0x20/0x20 [ 16.516786] ? locks_remove_file+0x3fa/0x5a0 [ 16.517120] ? fcntl_setlk+0x10c0/0x10c0 [ 16.517407] ? free_fs_struct+0x4f/0x60 [ 16.517725] ? __fsnotify_parent+0xb4/0x3a0 [ 16.518071] ? fsnotify+0x1af0/0x1af0 [ 16.518448] ? rcu_note_context_switch+0x710/0x710 [ 16.518821] sock_release+0x8d/0x1e0 [ 16.519094] ? sock_release+0x1e0/0x1e0 [ 16.519384] sock_close+0x16/0x20 [ 16.519698] __fput+0x327/0x7e0 [ 16.519966] ? fput+0x140/0x140 [ 16.520269] ? _raw_spin_unlock_irq+0x27/0x70 [ 16.520604] ____fput+0x15/0x20 [ 16.520834] task_work_run+0x199/0x270 [ 16.521105] ? task_work_cancel+0x210/0x210 [ 16.521469] ? _raw_spin_unlock+0x22/0x30 [ 16.521848] ? switch_task_namespaces+0x87/0xc0 [ 16.522277] do_exit+0x9b5/0x1ad0 [ 16.522612] ? mm_update_next_owner+0x930/0x930 [ 16.523050] ? reacquire_held_locks+0x1fd/0x3d0 [ 16.523480] ? find_held_lock+0x35/0x1d0 [ 16.523857] ? release_sock+0x1d4/0x2a0 [ 16.524221] ? lock_downgrade+0x990/0x990 [ 16.524950] ? lock_downgrade+0x990/0x990 [ 16.525212] ? do_raw_spin_trylock+0x190/0x190 [ 16.525485] ? tipc_group_delete+0x2c0/0x3c0 [ 16.525773] ? __local_bh_enable_ip+0x9d/0x160 [ 16.526044] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.526339] ? trace_hardirqs_on+0xd/0x10 [ 16.526584] ? __local_bh_enable_ip+0x9d/0x160 [ 16.526856] ? release_sock+0x1d4/0x2a0 [ 16.527095] ? tipc_nametbl_build_group+0x27a/0x370 [ 16.527394] ? tipc_setsockopt+0x703/0xc00 [ 16.527645] ? tipc_sk_leave+0x200/0x200 [ 16.527920] ? security_socket_setsockopt+0x89/0xb0 [ 16.528216] ? SyS_setsockopt+0x215/0x360 [ 16.528526] do_group_exit+0x149/0x400 [ 16.528804] ? SyS_recv+0x40/0x40 [ 16.529078] ? SyS_exit+0x30/0x30 [ 16.529324] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.529678] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.530045] SyS_exit_group+0x1d/0x20 [ 16.530315] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.530647] RIP: 0033:0x433a29 [ 16.530873] RSP: 002b:00007ffead686d38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 16.531415] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000433a29 [ 16.532046] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 16.532553] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 16.533057] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 00007ffead686e58 [ 16.533563] R13: 00007ffead686e68 R14: 0000000000000002 R15: 0000000000000000 [ 16.534135] [ 16.534251] Allocated by task 2995: [ 16.534553] save_stack+0x43/0xd0 [ 16.534795] kasan_kmalloc+0xad/0xe0 [ 16.535083] kmem_cache_alloc_trace+0x136/0x750 [ 16.535424] tipc_group_create+0x116/0x9c0 [ 16.535697] tipc_setsockopt+0x25e/0xc00 [ 16.535952] SyS_setsockopt+0x189/0x360 [ 16.536220] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.536637] [ 16.536788] Freed by task 2995: [ 16.537074] save_stack+0x43/0xd0 [ 16.537399] kasan_slab_free+0x71/0xc0 [ 16.537752] kfree+0xca/0x250 [ 16.538037] tipc_group_delete+0x2c0/0x3c0 [ 16.538424] tipc_setsockopt+0xb33/0xc00 [ 16.538776] SyS_setsockopt+0x189/0x360 [ 16.539113] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.539457] [ 16.539610] The buggy address belongs to the object at ffff88003c6e6300 [ 16.539610] which belongs to the cache kmalloc-192 of size 192 [ 16.540607] The buggy address is located 108 bytes inside of [ 16.540607] 192-byte region [ffff88003c6e6300, ffff88003c6e63c0) [ 16.541437] The buggy address belongs to the page: [ 16.541745] page:ffffea0000f1b980 count:1 mapcount:0 mapping:ffff88003c6e6000 index:0xffff88003c6e6600 [ 16.542558] flags: 0x100000000000100(slab) [ 16.542861] raw: 0100000000000100 ffff88003c6e6000 ffff88003c6e6600 000000010000000e [ 16.543480] raw: ffff88003e801138 ffffea0000f6e620 ffff88003e800040 0000000000000000 [ 16.544025] page dumped because: kasan: bad access detected [ 16.544426] [ 16.544544] Memory state around the buggy address: [ 16.544944] ffff88003c6e6200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 16.545465] ffff88003c6e6280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 16.546379] >ffff88003c6e6300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 16.546847] ^ [ 16.547344] ffff88003c6e6380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 16.547994] ffff88003c6e6400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 16.548598] ================================================================== [ 16.549242] Disabling lock debugging due to kernel taint [ 16.549624] Kernel panic - not syncing: panic_on_warn set ... [ 16.549624] [ 16.550295] CPU: 1 PID: 2995 Comm: syzkaller085005 Tainted: G B 4.14.0-rc5-next-20171018+ #8 [ 16.550945] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 16.551472] Call Trace: [ 16.551649] dump_stack+0x194/0x257 [ 16.551883] ? arch_local_irq_restore+0x53/0x53 [ 16.552193] ? kasan_end_report+0x32/0x50 [ 16.552494] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.552829] ? vsnprintf+0x1ed/0x1900 [ 16.553096] ? tipc_group_self+0xb0/0x1b0 [ 16.553390] panic+0x1e4/0x41c [ 16.553623] ? refcount_error_report+0x214/0x214 [ 16.553959] ? add_taint+0x1c/0x50 [ 16.554210] ? add_taint+0x1c/0x50 [ 16.554464] ? tipc_group_self+0x1a2/0x1b0 [ 16.554763] kasan_end_report+0x50/0x50 [ 16.555041] kasan_report+0x144/0x340 [ 16.555310] __asan_report_load4_noabort+0x14/0x20 [ 16.555653] tipc_group_self+0x1a2/0x1b0 [ 16.555938] tipc_sk_leave+0xfc/0x200 [ 16.556226] ? tipc_sk_withdraw+0x6b0/0x6b0 [ 16.556574] ? __local_bh_enable_ip+0x9d/0x160 [ 16.556976] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.557465] ? lock_sock_nested+0x91/0x110 [ 16.557877] ? trace_hardirqs_on+0xd/0x10 [ 16.558252] ? __local_bh_enable_ip+0x9d/0x160 [ 16.558668] tipc_release+0x154/0xfe0 [ 16.559015] ? kernel_text_address+0x102/0x140 [ 16.559430] ? tipc_sk_backlog_rcv+0x370/0x370 [ 16.559790] ? __kernel_text_address+0xd/0x40 [ 16.560121] ? unwind_get_return_address+0x61/0xa0 [ 16.560468] ? __save_stack_trace+0x7e/0xd0 [ 16.560766] ? check_noncircular+0x20/0x20 [ 16.561060] ? check_noncircular+0x20/0x20 [ 16.561381] ? locks_remove_file+0x3fa/0x5a0 [ 16.561795] ? fcntl_setlk+0x10c0/0x10c0 [ 16.562084] ? free_fs_struct+0x4f/0x60 [ 16.562363] ? __fsnotify_parent+0xb4/0x3a0 [ 16.562662] ? fsnotify+0x1af0/0x1af0 [ 16.562926] ? rcu_note_context_switch+0x710/0x710 [ 16.563273] sock_release+0x8d/0x1e0 [ 16.563553] ? sock_release+0x1e0/0x1e0 [ 16.563860] sock_close+0x16/0x20 [ 16.564173] __fput+0x327/0x7e0 [ 16.564478] ? fput+0x140/0x140 [ 16.564725] ? _raw_spin_unlock_irq+0x27/0x70 [ 16.565041] ____fput+0x15/0x20 [ 16.565302] task_work_run+0x199/0x270 [ 16.565575] ? task_work_cancel+0x210/0x210 [ 16.565879] ? _raw_spin_unlock+0x22/0x30 [ 16.566172] ? switch_task_namespaces+0x87/0xc0 [ 16.566457] do_exit+0x9b5/0x1ad0 [ 16.566664] ? mm_update_next_owner+0x930/0x930 [ 16.566951] ? reacquire_held_locks+0x1fd/0x3d0 [ 16.567693] ? find_held_lock+0x35/0x1d0 [ 16.568025] ? release_sock+0x1d4/0x2a0 [ 16.568414] ? lock_downgrade+0x990/0x990 [ 16.568768] ? lock_downgrade+0x990/0x990 [ 16.569137] ? do_raw_spin_trylock+0x190/0x190 [ 16.569477] ? tipc_group_delete+0x2c0/0x3c0 [ 16.569809] ? __local_bh_enable_ip+0x9d/0x160 [ 16.570101] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.570490] ? trace_hardirqs_on+0xd/0x10 [ 16.570821] ? __local_bh_enable_ip+0x9d/0x160 [ 16.571143] ? release_sock+0x1d4/0x2a0 [ 16.571424] ? tipc_nametbl_build_group+0x27a/0x370 [ 16.571774] ? tipc_setsockopt+0x703/0xc00 [ 16.572070] ? tipc_sk_leave+0x200/0x200 [ 16.572368] ? security_socket_setsockopt+0x89/0xb0 [ 16.572723] ? SyS_setsockopt+0x215/0x360 [ 16.573014] do_group_exit+0x149/0x400 [ 16.573285] ? SyS_recv+0x40/0x40 [ 16.573528] ? SyS_exit+0x30/0x30 [ 16.573775] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.574130] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.574580] SyS_exit_group+0x1d/0x20 [ 16.574851] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.575207] RIP: 0033:0x433a29 [ 16.575432] RSP: 002b:00007ffead686d38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 16.575965] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000433a29 [ 16.576477] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 16.577213] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 16.577870] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 00007ffead686e58 [ 16.578522] R13: 00007ffead686e68 R14: 0000000000000002 R15: 0000000000000000 [ 16.580333] Dumping ftrace buffer: [ 16.580671] (ftrace buffer empty) [ 16.580996] Kernel Offset: disabled [ 16.581305] Rebooting in 86400 seconds..