bisecting fixing commit since 0c88e405c97ed1828443b67891e6d4bb6e56cd4e building syzkaller on 486f93ef445f733b35d844f33ba9edeb8423f5fa testing commit 0c88e405c97ed1828443b67891e6d4bb6e56cd4e with gcc (GCC) 8.1.0 kernel signature: 77c4dd9db3f4fbe16788f8858629fb54e0549859c09e2aceeea081a1f58b314c all runs: crashed: BUG: corrupted list in kobject_add_internal testing current HEAD 2263955bf7e71ca8419b64d7a60510aad29002f6 testing commit 2263955bf7e71ca8419b64d7a60510aad29002f6 with gcc (GCC) 8.1.0 kernel signature: 372ae86612bf56556b3067dbb7dc42df90e75d97b9c6b4889d8071b2e472325f run #0: crashed: BUG: corrupted list in sysfs_warn_dup run #1: crashed: BUG: corrupted list in kobject_add_internal run #2: crashed: BUG: corrupted list in kobject_add_internal run #3: crashed: BUG: corrupted list in kobject_add_internal run #4: crashed: BUG: corrupted list in kobject_add_internal run #5: crashed: BUG: corrupted list in kobject_add_internal run #6: crashed: BUG: corrupted list in kobject_add_internal run #7: crashed: BUG: corrupted list in kobject_add_internal run #8: crashed: BUG: corrupted list in kobject_add_internal run #9: crashed: BUG: corrupted list in kobject_add_internal revisions tested: 2, total time: 25m26.831659801s (build: 18m44.836123534s, test: 6m3.539681482s) the crash still happens on HEAD commit msg: Linux 4.19.170 crash: BUG: corrupted list in kobject_add_internal IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready list_add double add: new=ffff8880ab690c18, prev=ffff8880ab690c18, next=ffff88823b2b1200. wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:31! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 8511 Comm: kworker/u5:3 Not tainted 4.19.170-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: hci2 hci_rx_work RIP: 0010:__list_add_valid+0xaa/0xb0 lib/list_debug.c:29 Code: e8 eb a9 48 89 f7 48 89 75 e8 e8 f1 cc 45 fe 48 8b 75 e8 eb bb 48 89 f2 48 89 d9 4c 89 e6 48 c7 c7 40 08 50 88 e8 34 2d 3a 04 <0f> 0b 0f 1f 40 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 55 RSP: 0018:ffff8880a9c0f7e8 EFLAGS: 00010282 RAX: 0000000000000058 RBX: ffff88823b2b1200 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff88500600 RDI: ffffffff8bad66e0 RBP: ffff8880a9c0f800 R08: ffffed1017464e99 R09: ffffed1017464e98 R10: ffffed1017464e98 R11: ffff8880ba3274c7 R12: ffff8880ab690c18 R13: ffff8880ab690c28 R14: ffff88823b2b1200 R15: ffff8880ab690c10 FS: 0000000000000000(0000) GS:ffff8880ba300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000768000 CR3: 000000009766b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_add include/linux/list.h:60 [inline] list_add_tail include/linux/list.h:93 [inline] kobj_kset_join lib/kobject.c:188 [inline] kobject_add_internal+0x165/0x8d0 lib/kobject.c:238 kobject_add_varg lib/kobject.c:382 [inline] kobject_add+0x10f/0x170 lib/kobject.c:426 device_add+0x33e/0x16b0 drivers/base/core.c:2106 hci_conn_add_sysfs+0x8e/0x160 net/bluetooth/hci_sysfs.c:53 hci_sync_conn_complete_evt.isra.112+0x8bc/0xa50 net/bluetooth/hci_event.c:4091 hci_event_packet+0x1a08/0x6840 net/bluetooth/hci_event.c:5857 hci_rx_work+0x33e/0xa60 net/bluetooth/hci_core.c:4359 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2155 worker_thread+0x85/0xb60 kernel/workqueue.c:2298 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Modules linked in: ---[ end trace 7952788ebf85db2b ]--- RIP: 0010:__list_add_valid+0xaa/0xb0 lib/list_debug.c:29 Code: e8 eb a9 48 89 f7 48 89 75 e8 e8 f1 cc 45 fe 48 8b 75 e8 eb bb 48 89 f2 48 89 d9 4c 89 e6 48 c7 c7 40 08 50 88 e8 34 2d 3a 04 <0f> 0b 0f 1f 40 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 55 RSP: 0018:ffff8880a9c0f7e8 EFLAGS: 00010282 RAX: 0000000000000058 RBX: ffff88823b2b1200 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff88500600 RDI: ffffffff8bad66e0 RBP: ffff8880a9c0f800 R08: ffffed1017464e99 R09: ffffed1017464e98 R10: ffffed1017464e98 R11: ffff8880ba3274c7 R12: ffff8880ab690c18 R13: ffff8880ab690c28 R14: ffff88823b2b1200 R15: ffff8880ab690c10 FS: 0000000000000000(0000) GS:ffff8880ba300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000768000 CR3: 000000009766b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400