bisecting fixing commit since 0c88e405c97ed1828443b67891e6d4bb6e56cd4e building syzkaller on 486f93ef445f733b35d844f33ba9edeb8423f5fa testing commit 0c88e405c97ed1828443b67891e6d4bb6e56cd4e with gcc (GCC) 8.4.1 20210217 kernel signature: 1d33f5de7e3940c9260299b87800224b88f99cc511f137186fb8441b392ec1bb run #0: crashed: BUG: corrupted list in hci_rx_work 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 run #10: crashed: BUG: corrupted list in kobject_add_internal run #11: crashed: BUG: corrupted list in kobject_add_internal run #12: crashed: BUG: corrupted list in kobject_add_internal run #13: crashed: BUG: corrupted list in kobject_add_internal run #14: crashed: BUG: corrupted list in kobject_add_internal run #15: crashed: BUG: corrupted list in kobject_add_internal run #16: crashed: BUG: corrupted list in kobject_add_internal run #17: crashed: BUG: corrupted list in kobject_add_internal run #18: crashed: BUG: corrupted list in kobject_add_internal run #19: crashed: BUG: corrupted list in kobject_add_internal testing current HEAD 2965db2e004cf9c92b87c1f559e9812c0ae878c1 testing commit 2965db2e004cf9c92b87c1f559e9812c0ae878c1 with gcc (GCC) 8.4.1 20210217 kernel signature: fb1b1b027ae4f3ed5a15deabdfde475da0560986af7cc1b6e766136fb4e6a29a run #0: crashed: BUG: corrupted list in kobject_add_internal run #1: crashed: BUG: corrupted list in kobject_add_internal run #2: crashed: BUG: corrupted list in sysfs_warn_dup 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: 27m18.993352234s (build: 19m52.495153545s, test: 6m43.499133035s) the crash still happens on HEAD commit msg: Linux 4.19.188 crash: BUG: corrupted list in kobject_add_internal IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready list_add double add: new=ffff888090793298, prev=ffff888090793298, next=ffff8880b5927700. ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:31! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 8454 Comm: kworker/u5:4 Not tainted 4.19.188-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: hci3 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 61 7f 44 fe 48 8b 75 e8 eb bb 48 89 f2 48 89 d9 4c 89 e6 48 c7 c7 00 1f 50 88 e8 42 91 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:ffff8880aae277e8 EFLAGS: 00010282 RAX: 0000000000000058 RBX: ffff8880b5927700 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff88501cc0 RDI: ffffffff8bad9720 RBP: ffff8880aae27800 R08: ffffed1017444e99 R09: ffffed1017444e98 R10: ffffed1017444e98 R11: ffff8880ba2274c7 R12: ffff888090793298 R13: ffff8880907932a8 R14: ffff8880b5927700 R15: ffff888090793290 FS: 0000000000000000(0000) GS:ffff8880ba200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f097413ea21 CR3: 00000000990d5000 CR4: 00000000001406f0 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:2121 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+0x1a08/0x6890 net/bluetooth/hci_event.c:5857 hci_rx_work+0x385/0xa70 net/bluetooth/hci_core.c:4361 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Modules linked in: ---[ end trace c804a0f59f6be2da ]--- RIP: 0010:__list_add_valid+0xaa/0xb0 lib/list_debug.c:29 Code: e8 eb a9 48 89 f7 48 89 75 e8 e8 61 7f 44 fe 48 8b 75 e8 eb bb 48 89 f2 48 89 d9 4c 89 e6 48 c7 c7 00 1f 50 88 e8 42 91 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:ffff8880aae277e8 EFLAGS: 00010282 RAX: 0000000000000058 RBX: ffff8880b5927700 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff88501cc0 RDI: ffffffff8bad9720 RBP: ffff8880aae27800 R08: ffffed1017444e99 R09: ffffed1017444e98 R10: ffffed1017444e98 R11: ffff8880ba2274c7 R12: ffff888090793298 R13: ffff8880907932a8 R14: ffff8880b5927700 R15: ffff888090793290 FS: 0000000000000000(0000) GS:ffff8880ba200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f097413ea21 CR3: 000000000986d000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400