syzkaller login: [ 17.422956] ================================================================== [ 17.423660] BUG: KASAN: use-after-free in tipc_group_self+0x1a2/0x1b0 [ 17.424235] Read of size 4 at addr ffff88006a1b2c6c by task syzkaller921776/3003 [ 17.424927] executing program [ 17.425096] CPU: 3 PID: 3003 Comm: syzkaller921776 Not tainted 4.14.0-rc5-next-20171018+ #8 [ 17.425980] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 17.426521] Call Trace: [ 17.426690] dump_stack+0x194/0x257 [ 17.426919] ? arch_local_irq_restore+0x53/0x53 [ 17.427211] ? show_regs_print_info+0x65/0x65 [ 17.427498] ? tipc_group_self+0x1a2/0x1b0 [ 17.427762] print_address_description+0x73/0x250 [ 17.428064] ? tipc_group_self+0x1a2/0x1b0 [ 17.428328] kasan_report+0x25b/0x340 [ 17.428569] __asan_report_load4_noabort+0x14/0x20 [ 17.428875] tipc_group_self+0x1a2/0x1b0 [ 17.429164] tipc_sk_leave+0xfc/0x200 [ 17.429403] ? tipc_sk_withdraw+0x6b0/0x6b0 [ 17.429670] ? __local_bh_enable_ip+0x9d/0x160 [ 17.430091] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 17.430401] ? lock_sock_nested+0x91/0x110 [ 17.430668] ? trace_hardirqs_on+0xd/0x10 [ 17.430970] ? __local_bh_enable_ip+0x9d/0x160 [ 17.431358] tipc_release+0x154/0xfe0 [ 17.431603] ? mntput_no_expire+0x130/0xa90 [ 17.431901] ? tipc_sk_backlog_rcv+0x370/0x370 [ 17.432208] ? lock_release+0xa40/0xa40 [ 17.432456] ? dentry_free+0xcd/0x130 [ 17.432692] ? rcu_read_lock_sched_held+0x108/0x120 [ 17.433025] ? kmem_cache_free+0x249/0x280 [ 17.433324] ? dentry_free+0xd2/0x130 [ 17.433585] ? locks_remove_file+0x3fa/0x5a0 [ 17.433877] ? fcntl_setlk+0x10c0/0x10c0 [ 17.434493] ? __fsnotify_parent+0xb4/0x3a0 [ 17.434913] ? fsnotify+0x1af0/0x1af0 [ 17.435312] ? rcu_note_context_switch+0x710/0x710 [ 17.435839] sock_release+0x8d/0x1e0 [ 17.436460] ? sock_release+0x1e0/0x1e0 [ 17.436856] sock_close+0x16/0x20 [ 17.437198] __fput+0x327/0x7e0 [ 17.437531] ? fput+0x140/0x140 [ 17.437844] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 17.438370] ? _raw_spin_unlock_irq+0x27/0x70 [ 17.438772] ____fput+0x15/0x20 [ 17.439064] task_work_run+0x199/0x270 [ 17.439412] ? task_work_cancel+0x210/0x210 [ 17.439792] ? _raw_spin_unlock+0x22/0x30 [ 17.440160] ? switch_task_namespaces+0x87/0xc0 [ 17.440574] do_exit+0x9b5/0x1ad0 [ 17.440886] ? mm_update_next_owner+0x930/0x930 [ 17.441297] ? reacquire_held_locks+0x1fd/0x3d0 [ 17.441718] ? find_held_lock+0x35/0x1d0 [ 17.442178] ? release_sock+0x1d4/0x2a0 [ 17.442570] ? lock_downgrade+0x990/0x990 [ 17.443015] ? lock_downgrade+0x990/0x990 [ 17.443392] ? do_raw_spin_trylock+0x190/0x190 [ 17.443843] ? tipc_group_delete+0x2c0/0x3c0 [ 17.444249] ? __local_bh_enable_ip+0x9d/0x160 [ 17.444658] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 17.445105] ? trace_hardirqs_on+0xd/0x10 [ 17.445473] ? __local_bh_enable_ip+0x9d/0x160 [ 17.446466] ? release_sock+0x1d4/0x2a0 [ 17.446847] ? tipc_nametbl_build_group+0x27a/0x370 [ 17.447299] ? tipc_setsockopt+0x703/0xc00 [ 17.447677] ? tipc_sk_leave+0x200/0x200 [ 17.448054] ? security_socket_setsockopt+0x89/0xb0 [ 17.448505] ? SyS_setsockopt+0x215/0x360 [ 17.448880] do_group_exit+0x149/0x400 [ 17.449229] ? SyS_recv+0x40/0x40 [ 17.449543] ? SyS_exit+0x30/0x30 [ 17.449855] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 17.450345] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 17.450786] SyS_exit_group+0x1d/0x20 [ 17.451119] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 17.451528] RIP: 0033:0x433a29 [ 17.451804] RSP: 002b:00007ffe7e97f9f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 17.452465] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000433a29 [ 17.453084] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 17.453704] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 17.454357] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 0000000000000000 [ 17.454978] R13: 0000000000401860 R14: 00000000004018f0 R15: 0000000000000000 [ 17.455620] [ 17.455765] Allocated by task 3003: [ 17.456081] save_stack+0x43/0xd0 [ 17.456380] kasan_kmalloc+0xad/0xe0 [ 17.456701] kmem_cache_alloc_trace+0x136/0x750 [ 17.457104] tipc_group_create+0x116/0x9c0 [ 17.457468] tipc_setsockopt+0x25e/0xc00 [ 17.457816] SyS_setsockopt+0x189/0x360 [ 17.458214] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 17.458638] [ 17.458791] Freed by task 3003: [ 17.459068] save_stack+0x43/0xd0 [ 17.459375] kasan_slab_free+0x71/0xc0 [ 17.459740] kfree+0xca/0x250 [ 17.460007] tipc_group_delete+0x2c0/0x3c0 [ 17.460344] tipc_setsockopt+0xb33/0xc00 [ 17.460636] SyS_setsockopt+0x189/0x360 [ 17.460943] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 17.461309] [ 17.461428] The buggy address belongs to the object at ffff88006a1b2c00 [ 17.461428] which belongs to the cache kmalloc-192 of size 192 [ 17.462419] The buggy address is located 108 bytes inside of [ 17.462419] 192-byte region [ffff88006a1b2c00, ffff88006a1b2cc0) [ 17.463272] The buggy address belongs to the page: [ 17.463637] page:ffffea0001a86c80 count:1 mapcount:0 mapping:ffff88006a1b2000 index:0xffff88006a1b2000 [ 17.464439] flags: 0x500000000000100(slab) [ 17.464803] raw: 0500000000000100 ffff88006a1b2000 ffff88006a1b2000 000000010000000b [ 17.465368] raw: ffffea0001b69fe0 ffffea0001b69d20 ffff88003e800040 0000000000000000 [ 17.465943] page dumped because: kasan: bad access detected [ 17.466373] [ 17.466486] Memory state around the buggy address: [ 17.466861] ffff88006a1b2b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 17.467366] ffff88006a1b2b80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 17.467925] >ffff88006a1b2c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 17.468513] ^ [ 17.469062] ffff88006a1b2c80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 17.469616] ffff88006a1b2d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 17.470189] ================================================================== [ 17.470712] Disabling lock debugging due to kernel taint [ 17.471153] Kernel panic - not syncing: panic_on_warn set ... [ 17.471153] [ 17.471672] CPU: 3 PID: 3003 Comm: syzkaller921776 Tainted: G B 4.14.0-rc5-next-20171018+ #8 [ 17.472740] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 17.473619] Call Trace: [ 17.473910] dump_stack+0x194/0x257 [ 17.474306] ? arch_local_irq_restore+0x53/0x53 [ 17.474813] ? kasan_end_report+0x32/0x50 [ 17.475243] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 17.475608] ? vsnprintf+0x1ed/0x1900 [ 17.475897] ? tipc_group_self+0xb0/0x1b0 [ 17.476238] panic+0x1e4/0x41c [ 17.476481] ? refcount_error_report+0x214/0x214 [ 17.476843] ? add_taint+0x1c/0x50 [ 17.477118] ? add_taint+0x1c/0x50 [ 17.477405] ? tipc_group_self+0x1a2/0x1b0 [ 17.477724] kasan_end_report+0x50/0x50 [ 17.478064] kasan_report+0x144/0x340 [ 17.478375] __asan_report_load4_noabort+0x14/0x20 [ 17.478744] tipc_group_self+0x1a2/0x1b0 [ 17.479058] tipc_sk_leave+0xfc/0x200 [ 17.479364] ? tipc_sk_withdraw+0x6b0/0x6b0 [ 17.479693] ? __local_bh_enable_ip+0x9d/0x160 [ 17.480046] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 17.480436] ? lock_sock_nested+0x91/0x110 [ 17.480757] ? trace_hardirqs_on+0xd/0x10 [ 17.481074] ? __local_bh_enable_ip+0x9d/0x160 [ 17.481436] tipc_release+0x154/0xfe0 [ 17.481725] ? mntput_no_expire+0x130/0xa90 [ 17.482088] ? tipc_sk_backlog_rcv+0x370/0x370 [ 17.482456] ? lock_release+0xa40/0xa40 [ 17.482755] ? dentry_free+0xcd/0x130 [ 17.483059] ? rcu_read_lock_sched_held+0x108/0x120 [ 17.483451] ? kmem_cache_free+0x249/0x280 [ 17.483787] ? dentry_free+0xd2/0x130 [ 17.484087] ? locks_remove_file+0x3fa/0x5a0 [ 17.484449] ? fcntl_setlk+0x10c0/0x10c0 [ 17.484768] ? __fsnotify_parent+0xb4/0x3a0 [ 17.485106] ? fsnotify+0x1af0/0x1af0 [ 17.485423] ? rcu_note_context_switch+0x710/0x710 [ 17.486147] sock_release+0x8d/0x1e0 [ 17.486443] ? sock_release+0x1e0/0x1e0 [ 17.486709] sock_close+0x16/0x20 [ 17.486936] __fput+0x327/0x7e0 [ 17.487181] ? fput+0x140/0x140 [ 17.487450] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 17.488002] ? _raw_spin_unlock_irq+0x27/0x70 [ 17.488442] ____fput+0x15/0x20 [ 17.488760] task_work_run+0x199/0x270 [ 17.489142] ? task_work_cancel+0x210/0x210 [ 17.489540] ? _raw_spin_unlock+0x22/0x30 [ 17.489952] ? switch_task_namespaces+0x87/0xc0 [ 17.490432] do_exit+0x9b5/0x1ad0 [ 17.490812] ? mm_update_next_owner+0x930/0x930 [ 17.491284] ? reacquire_held_locks+0x1fd/0x3d0 [ 17.491718] ? find_held_lock+0x35/0x1d0 [ 17.492089] ? release_sock+0x1d4/0x2a0 [ 17.492441] ? lock_downgrade+0x990/0x990 [ 17.492817] ? lock_downgrade+0x990/0x990 [ 17.493199] ? do_raw_spin_trylock+0x190/0x190 [ 17.493611] ? tipc_group_delete+0x2c0/0x3c0 [ 17.494052] ? __local_bh_enable_ip+0x9d/0x160 [ 17.494463] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 17.494931] ? trace_hardirqs_on+0xd/0x10 [ 17.495300] ? __local_bh_enable_ip+0x9d/0x160 [ 17.495707] ? release_sock+0x1d4/0x2a0 [ 17.496062] ? tipc_nametbl_build_group+0x27a/0x370 [ 17.496511] ? tipc_setsockopt+0x703/0xc00 [ 17.496889] ? tipc_sk_leave+0x200/0x200 [ 17.497248] ? security_socket_setsockopt+0x89/0xb0 [ 17.497685] ? SyS_setsockopt+0x215/0x360 [ 17.498101] do_group_exit+0x149/0x400 [ 17.498443] ? SyS_recv+0x40/0x40 [ 17.498800] ? SyS_exit+0x30/0x30 [ 17.499162] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 17.499611] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 17.500032] SyS_exit_group+0x1d/0x20 [ 17.500378] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 17.500794] RIP: 0033:0x433a29 [ 17.501078] RSP: 002b:00007ffe7e97f9f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 17.501756] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000433a29 [ 17.502400] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 17.503039] RBP: 0000000000000082 R08: 000000000000003c R09: 00000000000000e7 [ 17.503671] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 0000000000000000 [ 17.504317] R13: 0000000000401860 R14: 00000000004018f0 R15: 0000000000000000 [ 17.505043] Dumping ftrace buffer: [ 17.505358] (ftrace buffer empty) [ 17.505684] Kernel Offset: disabled [ 17.506085] Rebooting in 86400 seconds..