bisecting fixing commit since 14b58326976de6ef3998eefec1dd7f8b38b97a75 building syzkaller on ff51e5229e0ee846d2fd687cb0dbca13de758c66 testing commit 14b58326976de6ef3998eefec1dd7f8b38b97a75 with gcc (GCC) 8.4.1 20210217 kernel signature: 8a79381ec29208e8d3d8139a3ac4d54e0b4a12a849ef257902b8dad8f0554e99 run #0: crashed: BUG: corrupted list in l2cap_chan_put run #1: crashed: BUG: corrupted list in l2cap_chan_put run #2: crashed: BUG: corrupted list in l2cap_chan_put run #3: crashed: BUG: corrupted list in l2cap_chan_put run #4: crashed: BUG: corrupted list in l2cap_chan_put run #5: crashed: BUG: corrupted list in l2cap_chan_put run #6: crashed: BUG: corrupted list in l2cap_chan_put run #7: crashed: BUG: corrupted list in l2cap_chan_put run #8: crashed: BUG: corrupted list in l2cap_chan_put run #9: crashed: BUG: corrupted list in l2cap_chan_put run #10: crashed: BUG: corrupted list in l2cap_chan_put run #11: crashed: BUG: corrupted list in l2cap_chan_put run #12: crashed: KASAN: use-after-free Read in l2cap_chan_put run #13: crashed: BUG: corrupted list in l2cap_chan_put run #14: crashed: BUG: corrupted list in l2cap_chan_put run #15: crashed: BUG: corrupted list in l2cap_chan_put run #16: crashed: BUG: corrupted list in l2cap_chan_put run #17: crashed: BUG: corrupted list in l2cap_chan_put run #18: crashed: BUG: corrupted list in l2cap_chan_put run #19: crashed: BUG: corrupted list in l2cap_chan_put testing current HEAD 7d7d1c0ab3eb7c8d8f63a126535018007823b207 testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 with gcc (GCC) 8.4.1 20210217 kernel signature: 04286924289d4388370008e19b05fae73ed06743a7c3b860e20013884e15c6e3 all runs: crashed: BUG: corrupted list in l2cap_chan_put revisions tested: 2, total time: 34m52.280760876s (build: 15m53.655030761s, test: 18m35.862085863s) the crash still happens on HEAD commit msg: Linux 4.14.232 crash: BUG: corrupted list in l2cap_chan_put bond0 (unregistering): Releasing backup interface bond_slave_0 bond0 (unregistering): Released all slaves IPVS: ftp: loaded support on port[0] = 21 list_del corruption, ffff8881ed5a1728->next is LIST_POISON1 (dead000000000100) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:47! invalid opcode: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 0 PID: 7095 Comm: kworker/u5:2 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: hci0 hci_rx_work task: ffff8881d93cc240 task.stack: ffff8881da9b0000 RIP: 0010:__list_del_entry_valid.cold.1+0x26/0x4a lib/list_debug.c:45 RSP: 0018:ffff8881da9b77e0 EFLAGS: 00010282 RAX: 000000000000004e RBX: ffff8881ed5a1728 RCX: 0000000000000000 RDX: 000000000000004e RSI: ffffffff86cbeca0 RDI: ffffed103b536ef3 RBP: ffff8881da9b77f8 R08: ffff8881d93ccb38 R09: 0000000000000000 R10: 0000000000000000 R11: dffffc0000000000 R12: dead000000000200 R13: dead000000000100 R14: ffff8881e2284340 R15: ffff8881e22843c0 FS: 0000000000000000(0000) GS:ffff8881f6600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000538608 CR3: 0000000007e6a001 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_del_entry include/linux/list.h:117 [inline] list_del include/linux/list.h:125 [inline] l2cap_chan_destroy net/bluetooth/l2cap_core.c:479 [inline] kref_put include/linux/kref.h:70 [inline] l2cap_chan_put+0x49/0x1a0 net/bluetooth/l2cap_core.c:496 l2cap_conless_channel net/bluetooth/l2cap_core.c:6982 [inline] l2cap_recv_frame+0xeca/0x9e10 net/bluetooth/l2cap_core.c:7029 l2cap_recv_acldata+0x756/0x8a0 net/bluetooth/l2cap_core.c:7594 hci_acldata_packet net/bluetooth/hci_core.c:4068 [inline] hci_rx_work+0x5c9/0x8e0 net/bluetooth/hci_core.c:4251 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: 83 f9 ff 0f 0b 4c 89 e2 48 89 de 48 c7 c7 20 22 04 87 e8 f7 82 f9 ff 0f 0b 4c 89 ea 48 89 de 48 c7 c7 c0 21 04 87 e8 e3 82 f9 ff <0f> 0b 48 89 de 48 c7 c7 e0 22 04 87 e8 d2 82 f9 ff 0f 0b 48 89 RIP: __list_del_entry_valid.cold.1+0x26/0x4a lib/list_debug.c:45 RSP: ffff8881da9b77e0 ---[ end trace f991527149eb9da9 ]---