executing program syzkaller login: [ 16.061576] ================================================================== [ 16.062693] BUG: KASAN: use-after-free in tipc_group_self+0x1a2/0x1b0 [ 16.063766] Read of size 4 at addr ffff88006bda4e6c by task syzkaller871082/3000 [ 16.064473] [ 16.064619] CPU: 2 PID: 3000 Comm: syzkaller871082 Not tainted 4.14.0-rc5-next-20171018+ #8 [ 16.065333] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 16.066025] Call Trace: [ 16.066260] dump_stack+0x194/0x257 [ 16.066649] ? arch_local_irq_restore+0x53/0x53 [ 16.067134] ? show_regs_print_info+0x65/0x65 [ 16.067476] ? tipc_group_self+0x1a2/0x1b0 [ 16.067772] print_address_description+0x73/0x250 [ 16.068121] ? tipc_group_self+0x1a2/0x1b0 [ 16.068439] kasan_report+0x25b/0x340 [ 16.068706] __asan_report_load4_noabort+0x14/0x20 [ 16.069065] tipc_group_self+0x1a2/0x1b0 [ 16.069370] tipc_sk_leave+0xfc/0x200 [ 16.069641] ? tipc_sk_withdraw+0x6b0/0x6b0 [ 16.069941] ? __local_bh_enable_ip+0x9d/0x160 [ 16.070280] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.070661] ? lock_sock_nested+0x91/0x110 [ 16.070954] ? trace_hardirqs_on+0xd/0x10 [ 16.071274] ? __local_bh_enable_ip+0x9d/0x160 [ 16.071617] tipc_release+0x154/0xfe0 [ 16.071888] ? mntput_no_expire+0x130/0xa90 [ 16.072217] ? tipc_sk_backlog_rcv+0x370/0x370 [ 16.072560] ? lock_release+0xa40/0xa40 [ 16.072839] ? dentry_free+0xcd/0x130 [ 16.073116] ? rcu_read_lock_sched_held+0x108/0x120 [ 16.073484] ? kmem_cache_free+0x249/0x280 [ 16.073782] ? dentry_free+0xd2/0x130 [ 16.074069] ? locks_remove_file+0x3fa/0x5a0 [ 16.074384] ? fcntl_setlk+0x10c0/0x10c0 [ 16.074690] ? __fsnotify_parent+0xb4/0x3a0 [ 16.075010] ? fsnotify+0x1af0/0x1af0 [ 16.075301] ? rcu_note_context_switch+0x710/0x710 [ 16.075998] sock_release+0x8d/0x1e0 [ 16.076334] ? sock_release+0x1e0/0x1e0 [ 16.076674] sock_close+0x16/0x20 [ 16.077025] __fput+0x327/0x7e0 [ 16.077379] ? fput+0x140/0x140 [ 16.077726] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 16.078346] ? _raw_spin_unlock_irq+0x27/0x70 [ 16.078832] ____fput+0x15/0x20 [ 16.079199] task_work_run+0x199/0x270 [ 16.079623] ? task_work_cancel+0x210/0x210 [ 16.080074] ? _raw_spin_unlock+0x22/0x30 [ 16.080496] ? switch_task_namespaces+0x87/0xc0 [ 16.080980] do_exit+0x9b5/0x1ad0 [ 16.081357] ? mm_update_next_owner+0x930/0x930 [ 16.081720] ? reacquire_held_locks+0x1fd/0x3d0 [ 16.082082] ? find_held_lock+0x35/0x1d0 [ 16.082373] ? release_sock+0x1d4/0x2a0 [ 16.082659] ? lock_downgrade+0x990/0x990 [ 16.083178] ? lock_downgrade+0x990/0x990 [ 16.083481] ? do_raw_spin_trylock+0x190/0x190 [ 16.083801] ? tipc_group_delete+0x2c0/0x3c0 [ 16.084149] ? __local_bh_enable_ip+0x9d/0x160 [ 16.084515] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.084873] ? trace_hardirqs_on+0xd/0x10 [ 16.085271] ? __local_bh_enable_ip+0x9d/0x160 [ 16.085759] ? release_sock+0x1d4/0x2a0 [ 16.086186] ? tipc_nametbl_build_group+0x27a/0x370 [ 16.086729] ? tipc_setsockopt+0x703/0xc00 [ 16.087182] ? tipc_sk_leave+0x200/0x200 [ 16.087631] ? security_socket_setsockopt+0x89/0xb0 [ 16.088173] ? SyS_setsockopt+0x215/0x360 [ 16.088626] do_group_exit+0x149/0x400 [ 16.089042] ? SyS_recv+0x40/0x40 [ 16.089413] ? SyS_exit+0x30/0x30 [ 16.089772] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.090293] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.090805] SyS_exit_group+0x1d/0x20 [ 16.091234] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.091729] RIP: 0033:0x433a29 [ 16.092061] RSP: 002b:00007ffd134fdee8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 16.092871] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000433a29 [ 16.093629] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 16.094400] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 16.095155] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 00007ffd134fe008 [ 16.095898] R13: 00007ffd134fe018 R14: 0000000000000002 R15: 0000000000000000 [ 16.096462] [ 16.096563] Allocated by task 3000: [ 16.096782] save_stack+0x43/0xd0 [ 16.097016] kasan_kmalloc+0xad/0xe0 [ 16.097247] kmem_cache_alloc_trace+0x136/0x750 [ 16.097521] tipc_group_create+0x116/0x9c0 [ 16.097769] tipc_setsockopt+0x25e/0xc00 [ 16.098054] SyS_setsockopt+0x189/0x360 [ 16.098302] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.098579] [ 16.098677] Freed by task 3000: [ 16.098887] save_stack+0x43/0xd0 [ 16.099564] kasan_slab_free+0x71/0xc0 [ 16.099948] kfree+0xca/0x250 [ 16.100147] tipc_group_delete+0x2c0/0x3c0 [ 16.100490] tipc_setsockopt+0xb33/0xc00 [ 16.100910] SyS_setsockopt+0x189/0x360 [ 16.101277] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.101637] [ 16.101738] The buggy address belongs to the object at ffff88006bda4e00 [ 16.101738] which belongs to the cache kmalloc-192 of size 192 [ 16.102513] The buggy address is located 108 bytes inside of [ 16.102513] 192-byte region [ffff88006bda4e00, ffff88006bda4ec0) [ 16.103356] The buggy address belongs to the page: [ 16.103645] page:ffffea0001af6900 count:1 mapcount:0 mapping:ffff88006bda4000 index:0xffff88006bda4d00 [ 16.104225] flags: 0x500000000000100(slab) [ 16.104500] raw: 0500000000000100 ffff88006bda4000 ffff88006bda4d00 0000000100000004 [ 16.105206] raw: ffffea0001af6ce0 ffffea0001abdc20 ffff88003e800040 0000000000000000 [ 16.105909] page dumped because: kasan: bad access detected [ 16.106433] [ 16.106592] Memory state around the buggy address: [ 16.107184] ffff88006bda4d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 16.107929] ffff88006bda4d80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 16.108491] >ffff88006bda4e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 16.108922] ^ [ 16.109344] ffff88006bda4e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 16.109775] ffff88006bda4f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 16.110215] ================================================================== [ 16.110649] Disabling lock debugging due to kernel taint [ 16.111046] Kernel panic - not syncing: panic_on_warn set ... [ 16.111046] [ 16.111695] CPU: 2 PID: 3000 Comm: syzkaller871082 Tainted: G B 4.14.0-rc5-next-20171018+ #8 [ 16.112600] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 16.113329] Call Trace: [ 16.113569] dump_stack+0x194/0x257 [ 16.113910] ? arch_local_irq_restore+0x53/0x53 [ 16.114334] ? kasan_end_report+0x32/0x50 [ 16.114716] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.115209] ? vsnprintf+0x1ed/0x1900 [ 16.115557] ? tipc_group_self+0xb0/0x1b0 [ 16.115932] panic+0x1e4/0x41c [ 16.116226] ? refcount_error_report+0x214/0x214 [ 16.116663] ? add_taint+0x1c/0x50 [ 16.116986] ? add_taint+0x1c/0x50 [ 16.117310] ? tipc_group_self+0x1a2/0x1b0 [ 16.117697] kasan_end_report+0x50/0x50 [ 16.118379] kasan_report+0x144/0x340 [ 16.118732] __asan_report_load4_noabort+0x14/0x20 [ 16.119193] tipc_group_self+0x1a2/0x1b0 [ 16.119561] tipc_sk_leave+0xfc/0x200 [ 16.119983] ? tipc_sk_withdraw+0x6b0/0x6b0 [ 16.120383] ? __local_bh_enable_ip+0x9d/0x160 [ 16.120797] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.121248] ? lock_sock_nested+0x91/0x110 [ 16.121630] ? trace_hardirqs_on+0xd/0x10 [ 16.122009] ? __local_bh_enable_ip+0x9d/0x160 [ 16.122433] tipc_release+0x154/0xfe0 [ 16.122787] ? mntput_no_expire+0x130/0xa90 [ 16.123231] ? tipc_sk_backlog_rcv+0x370/0x370 [ 16.123644] ? lock_release+0xa40/0xa40 [ 16.123999] ? dentry_free+0xcd/0x130 [ 16.124335] ? rcu_read_lock_sched_held+0x108/0x120 [ 16.124780] ? kmem_cache_free+0x249/0x280 [ 16.125164] ? dentry_free+0xd2/0x130 [ 16.125505] ? locks_remove_file+0x3fa/0x5a0 [ 16.125896] ? fcntl_setlk+0x10c0/0x10c0 [ 16.126268] ? __fsnotify_parent+0xb4/0x3a0 [ 16.126663] ? fsnotify+0x1af0/0x1af0 [ 16.127071] ? rcu_note_context_switch+0x710/0x710 [ 16.127524] sock_release+0x8d/0x1e0 [ 16.127871] ? sock_release+0x1e0/0x1e0 [ 16.128232] sock_close+0x16/0x20 [ 16.128548] __fput+0x327/0x7e0 [ 16.128946] ? fput+0x140/0x140 [ 16.129246] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 16.129764] ? _raw_spin_unlock_irq+0x27/0x70 [ 16.130164] ____fput+0x15/0x20 [ 16.130461] task_work_run+0x199/0x270 [ 16.130790] ? task_work_cancel+0x210/0x210 [ 16.131081] ? _raw_spin_unlock+0x22/0x30 [ 16.131345] ? switch_task_namespaces+0x87/0xc0 [ 16.131645] do_exit+0x9b5/0x1ad0 [ 16.131856] ? mm_update_next_owner+0x930/0x930 [ 16.132157] ? reacquire_held_locks+0x1fd/0x3d0 [ 16.132451] ? find_held_lock+0x35/0x1d0 [ 16.132709] ? release_sock+0x1d4/0x2a0 [ 16.132944] ? lock_downgrade+0x990/0x990 [ 16.133263] ? lock_downgrade+0x990/0x990 [ 16.133638] ? do_raw_spin_trylock+0x190/0x190 [ 16.134049] ? tipc_group_delete+0x2c0/0x3c0 [ 16.134450] ? __local_bh_enable_ip+0x9d/0x160 [ 16.134796] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.135181] ? trace_hardirqs_on+0xd/0x10 [ 16.135434] ? __local_bh_enable_ip+0x9d/0x160 [ 16.135706] ? release_sock+0x1d4/0x2a0 [ 16.135946] ? tipc_nametbl_build_group+0x27a/0x370 [ 16.136304] ? tipc_setsockopt+0x703/0xc00 [ 16.136555] ? tipc_sk_leave+0x200/0x200 [ 16.136829] ? security_socket_setsockopt+0x89/0xb0 [ 16.137147] ? SyS_setsockopt+0x215/0x360 [ 16.137513] do_group_exit+0x149/0x400 [ 16.137874] ? SyS_recv+0x40/0x40 [ 16.138183] ? SyS_exit+0x30/0x30 [ 16.138390] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.138684] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.139038] SyS_exit_group+0x1d/0x20 [ 16.139953] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.140374] RIP: 0033:0x433a29 [ 16.140656] RSP: 002b:00007ffd134fdee8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 16.141322] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000433a29 [ 16.141949] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 16.142589] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 16.143330] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 00007ffd134fe008 [ 16.143920] R13: 00007ffd134fe018 R14: 0000000000000002 R15: 0000000000000000 [ 16.146997] Dumping ftrace buffer: [ 16.147371] (ftrace buffer empty) [ 16.147756] Kernel Offset: disabled [ 16.148130] Rebooting in 86400 seconds..