executing program syzkaller login: [ 16.558178] ================================================================== [ 16.558777] BUG: KASAN: use-after-free in tipc_group_self+0x1a2/0x1b0 [ 16.559420] Read of size 4 at addr ffff88006c92fe6c by task syzkaller268104/2993 [ 16.559940] [ 16.560081] CPU: 3 PID: 2993 Comm: syzkaller268104 Not tainted 4.14.0-rc5-next-20171018+ #8 [ 16.560662] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 16.561628] Call Trace: [ 16.561813] dump_stack+0x194/0x257 [ 16.562061] ? arch_local_irq_restore+0x53/0x53 [ 16.562377] ? show_regs_print_info+0x65/0x65 [ 16.562662] ? tipc_group_self+0x1a2/0x1b0 [ 16.562929] print_address_description+0x73/0x250 [ 16.563241] ? tipc_group_self+0x1a2/0x1b0 [ 16.563509] kasan_report+0x25b/0x340 [ 16.563753] __asan_report_load4_noabort+0x14/0x20 [ 16.564081] tipc_group_self+0x1a2/0x1b0 [ 16.564341] tipc_sk_leave+0xfc/0x200 [ 16.564582] ? tipc_sk_withdraw+0x6b0/0x6b0 [ 16.564857] ? __local_bh_enable_ip+0x9d/0x160 [ 16.565198] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.565546] ? lock_sock_nested+0x91/0x110 [ 16.565816] ? trace_hardirqs_on+0xd/0x10 [ 16.566104] ? __local_bh_enable_ip+0x9d/0x160 [ 16.566395] tipc_release+0x154/0xfe0 [ 16.566637] ? mntput_no_expire+0x130/0xa90 [ 16.566911] ? tipc_sk_backlog_rcv+0x370/0x370 [ 16.567219] ? lock_release+0xa40/0xa40 [ 16.567482] ? dentry_free+0xcd/0x130 [ 16.567727] ? rcu_read_lock_sched_held+0x108/0x120 [ 16.568047] ? kmem_cache_free+0x249/0x280 [ 16.568331] ? dentry_free+0xd2/0x130 [ 16.568578] ? locks_remove_file+0x3fa/0x5a0 [ 16.568860] ? fcntl_setlk+0x10c0/0x10c0 [ 16.569291] ? __fsnotify_parent+0xb4/0x3a0 [ 16.569762] ? fsnotify+0x1af0/0x1af0 [ 16.570197] ? rcu_note_context_switch+0x710/0x710 [ 16.570780] sock_release+0x8d/0x1e0 [ 16.571193] ? sock_release+0x1e0/0x1e0 [ 16.571539] sock_close+0x16/0x20 [ 16.571924] __fput+0x327/0x7e0 [ 16.572297] ? fput+0x140/0x140 [ 16.572661] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 16.573244] ? _raw_spin_unlock_irq+0x27/0x70 [ 16.573755] ____fput+0x15/0x20 [ 16.574073] task_work_run+0x199/0x270 [ 16.574400] ? task_work_cancel+0x210/0x210 [ 16.574879] ? _raw_spin_unlock+0x22/0x30 [ 16.575332] ? switch_task_namespaces+0x87/0xc0 [ 16.575844] do_exit+0x9b5/0x1ad0 [ 16.576230] ? mm_update_next_owner+0x930/0x930 [ 16.576729] ? reacquire_held_locks+0x1fd/0x3d0 [ 16.577407] ? find_held_lock+0x35/0x1d0 [ 16.577805] ? release_sock+0x1d4/0x2a0 [ 16.578167] ? lock_downgrade+0x990/0x990 [ 16.578536] ? lock_downgrade+0x990/0x990 [ 16.578914] ? do_raw_spin_trylock+0x190/0x190 [ 16.579274] ? tipc_group_delete+0x2c0/0x3c0 [ 16.579592] ? __local_bh_enable_ip+0x9d/0x160 [ 16.579936] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.580372] ? trace_hardirqs_on+0xd/0x10 [ 16.580676] ? __local_bh_enable_ip+0x9d/0x160 [ 16.581037] ? release_sock+0x1d4/0x2a0 [ 16.581333] ? tipc_nametbl_build_group+0x27a/0x370 [ 16.581711] ? tipc_setsockopt+0x703/0xc00 [ 16.582023] ? tipc_sk_leave+0x200/0x200 [ 16.582425] ? security_socket_setsockopt+0x89/0xb0 [ 16.583490] ? SyS_setsockopt+0x215/0x360 [ 16.583793] do_group_exit+0x149/0x400 [ 16.584072] ? SyS_recv+0x40/0x40 [ 16.584308] ? SyS_exit+0x30/0x30 [ 16.584542] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.584925] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.585277] SyS_exit_group+0x1d/0x20 [ 16.585560] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.585903] RIP: 0033:0x433a29 [ 16.586146] RSP: 002b:00007ffd9db4d4a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 16.586741] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000433a29 [ 16.587271] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 16.587807] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 16.588357] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 0000000000000000 [ 16.588943] R13: 0000000000401860 R14: 00000000004018f0 R15: 0000000000000000 [ 16.589711] [ 16.589910] Allocated by task 2993: [ 16.590274] save_stack+0x43/0xd0 [ 16.590647] kasan_kmalloc+0xad/0xe0 [ 16.590956] kmem_cache_alloc_trace+0x136/0x750 [ 16.591375] tipc_group_create+0x116/0x9c0 [ 16.591706] tipc_setsockopt+0x25e/0xc00 [ 16.592053] SyS_setsockopt+0x189/0x360 [ 16.592346] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.592697] [ 16.592873] Freed by task 2993: [ 16.593263] save_stack+0x43/0xd0 [ 16.593570] kasan_slab_free+0x71/0xc0 [ 16.593892] kfree+0xca/0x250 [ 16.594153] tipc_group_delete+0x2c0/0x3c0 [ 16.594512] tipc_setsockopt+0xb33/0xc00 [ 16.594884] SyS_setsockopt+0x189/0x360 [ 16.595245] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.595666] [ 16.595817] The buggy address belongs to the object at ffff88006c92fe00 [ 16.595817] which belongs to the cache kmalloc-192 of size 192 [ 16.596946] The buggy address is located 108 bytes inside of [ 16.596946] 192-byte region [ffff88006c92fe00, ffff88006c92fec0) [ 16.597927] The buggy address belongs to the page: [ 16.598344] page:ffffea0001b24bc0 count:1 mapcount:0 mapping:ffff88006c92f000 index:0x0 [ 16.599034] flags: 0x500000000000100(slab) [ 16.599404] raw: 0500000000000100 ffff88006c92f000 0000000000000000 0000000100000010 [ 16.600086] raw: ffffea0001af5260 ffffea0001af72e0 ffff88003e800040 0000000000000000 [ 16.600763] page dumped because: kasan: bad access detected [ 16.601254] [ 16.601401] Memory state around the buggy address: [ 16.601777] ffff88006c92fd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 16.602331] ffff88006c92fd80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 16.602935] >ffff88006c92fe00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 16.603581] ^ [ 16.604256] ffff88006c92fe80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 16.605181] ffff88006c92ff00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 16.605734] ================================================================== [ 16.606360] Disabling lock debugging due to kernel taint [ 16.606868] Kernel panic - not syncing: panic_on_warn set ... [ 16.606868] [ 16.607605] CPU: 3 PID: 2993 Comm: syzkaller268104 Tainted: G B 4.14.0-rc5-next-20171018+ #8 [ 16.608340] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 16.608961] Call Trace: [ 16.609206] dump_stack+0x194/0x257 [ 16.609486] ? arch_local_irq_restore+0x53/0x53 [ 16.609841] ? kasan_end_report+0x32/0x50 [ 16.610199] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.610590] ? vsnprintf+0x1ed/0x1900 [ 16.610889] ? tipc_group_self+0xb0/0x1b0 [ 16.611218] panic+0x1e4/0x41c [ 16.611452] ? refcount_error_report+0x214/0x214 [ 16.611815] ? add_taint+0x1c/0x50 [ 16.612239] ? add_taint+0x1c/0x50 [ 16.612649] ? tipc_group_self+0x1a2/0x1b0 [ 16.613042] kasan_end_report+0x50/0x50 [ 16.613487] kasan_report+0x144/0x340 [ 16.613898] __asan_report_load4_noabort+0x14/0x20 [ 16.614375] tipc_group_self+0x1a2/0x1b0 [ 16.614760] tipc_sk_leave+0xfc/0x200 [ 16.615144] ? tipc_sk_withdraw+0x6b0/0x6b0 [ 16.615537] ? __local_bh_enable_ip+0x9d/0x160 [ 16.615950] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.616385] ? lock_sock_nested+0x91/0x110 [ 16.616750] ? trace_hardirqs_on+0xd/0x10 [ 16.617131] ? __local_bh_enable_ip+0x9d/0x160 [ 16.617532] tipc_release+0x154/0xfe0 [ 16.617948] ? mntput_no_expire+0x130/0xa90 [ 16.618405] ? tipc_sk_backlog_rcv+0x370/0x370 [ 16.618839] ? lock_release+0xa40/0xa40 [ 16.619201] ? dentry_free+0xcd/0x130 [ 16.619532] ? rcu_read_lock_sched_held+0x108/0x120 [ 16.619963] ? kmem_cache_free+0x249/0x280 [ 16.620329] ? dentry_free+0xd2/0x130 [ 16.620660] ? locks_remove_file+0x3fa/0x5a0 [ 16.621058] ? fcntl_setlk+0x10c0/0x10c0 [ 16.621420] ? __fsnotify_parent+0xb4/0x3a0 [ 16.621829] ? fsnotify+0x1af0/0x1af0 [ 16.622176] ? rcu_note_context_switch+0x710/0x710 [ 16.622617] sock_release+0x8d/0x1e0 [ 16.622967] ? sock_release+0x1e0/0x1e0 [ 16.623324] sock_close+0x16/0x20 [ 16.623634] __fput+0x327/0x7e0 [ 16.623932] ? fput+0x140/0x140 [ 16.624225] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 16.624762] ? _raw_spin_unlock_irq+0x27/0x70 [ 16.625220] ____fput+0x15/0x20 [ 16.625518] task_work_run+0x199/0x270 [ 16.625856] ? task_work_cancel+0x210/0x210 [ 16.626205] ? _raw_spin_unlock+0x22/0x30 [ 16.626531] ? switch_task_namespaces+0x87/0xc0 [ 16.626904] do_exit+0x9b5/0x1ad0 [ 16.627180] ? mm_update_next_owner+0x930/0x930 [ 16.627544] ? reacquire_held_locks+0x1fd/0x3d0 [ 16.627916] ? find_held_lock+0x35/0x1d0 [ 16.628239] ? release_sock+0x1d4/0x2a0 [ 16.628551] ? lock_downgrade+0x990/0x990 [ 16.628878] ? lock_downgrade+0x990/0x990 [ 16.629302] ? do_raw_spin_trylock+0x190/0x190 [ 16.629706] ? tipc_group_delete+0x2c0/0x3c0 [ 16.630075] ? __local_bh_enable_ip+0x9d/0x160 [ 16.630455] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.630855] ? trace_hardirqs_on+0xd/0x10 [ 16.631274] ? __local_bh_enable_ip+0x9d/0x160 [ 16.631651] ? release_sock+0x1d4/0x2a0 [ 16.631999] ? tipc_nametbl_build_group+0x27a/0x370 [ 16.632453] ? tipc_setsockopt+0x703/0xc00 [ 16.632839] ? tipc_sk_leave+0x200/0x200 [ 16.633303] ? security_socket_setsockopt+0x89/0xb0 [ 16.633864] ? SyS_setsockopt+0x215/0x360 [ 16.634332] do_group_exit+0x149/0x400 [ 16.634747] ? SyS_recv+0x40/0x40 [ 16.635123] ? SyS_exit+0x30/0x30 [ 16.635525] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 16.638294] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 16.638646] SyS_exit_group+0x1d/0x20 [ 16.639000] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 16.639443] RIP: 0033:0x433a29 [ 16.639768] RSP: 002b:00007ffd9db4d4a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 16.640384] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000433a29 [ 16.641010] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 16.641760] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 16.642345] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 0000000000000000 [ 16.642927] R13: 0000000000401860 R14: 00000000004018f0 R15: 0000000000000000 [ 16.648926] Dumping ftrace buffer: [ 16.649298] (ftrace buffer empty) [ 16.649645] Kernel Offset: disabled [ 16.649999] Rebooting in 86400 seconds..