bisecting fixing commit since 14b58326976de6ef3998eefec1dd7f8b38b97a75
building syzkaller on 28ac5c9e93a44c3eb145195ffb55591be58ef510
testing commit 14b58326976de6ef3998eefec1dd7f8b38b97a75 with gcc (GCC) 8.4.1 20210217
kernel signature: 0de77850483db7582a8d4daeb58cf8348fc1d68d765bae5fee255224979a5bad
run #0: crashed: BUG: corrupted list in l2cap_chan_put
run #1: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #2: crashed: BUG: corrupted list in l2cap_chan_put
run #3: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #4: crashed: BUG: corrupted list in l2cap_chan_put
run #5: crashed: BUG: corrupted list in l2cap_chan_put
run #6: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #7: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #8: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #9: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #10: crashed: BUG: corrupted list in l2cap_chan_put
run #11: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #12: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
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: KASAN: use-after-free Read in l2cap_sock_shutdown
run #17: crashed: BUG: corrupted list in l2cap_chan_put
run #18: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #19: crashed: BUG: corrupted list in l2cap_chan_put
testing current HEAD cf256fbcbe347b7d0ff58fe2dfa382a156bd3694
testing commit cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 with gcc (GCC) 8.4.1 20210217
kernel signature: 9e5cdf07a7a1572f78d3b6b0120f647eddd73110f46aa2a8e0728d790674eddf
run #0: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #1: crashed: BUG: corrupted list in l2cap_chan_put
run #2: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #3: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #4: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #5: crashed: KASAN: use-after-free Read in l2cap_chan_put
run #6: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #7: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #8: crashed: KASAN: use-after-free Read in l2cap_sock_shutdown
run #9: crashed: BUG: corrupted list in l2cap_chan_put
revisions tested: 2, total time: 35m11.918774136s (build: 15m27.885773772s, test: 19m15.883345659s)
the crash still happens on HEAD
commit msg: Linux 4.14.231
crash: BUG: corrupted list in l2cap_chan_put
Bluetooth: hci3 command 0x0419 tx timeout
Bluetooth: hci4 command 0x0419 tx timeout
Bluetooth: hci5 command 0x0419 tx timeout
list_del corruption, ffff8881c5f0b8e8->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: 1 PID: 7242 Comm: kworker/u5:4 Not tainted 4.14.231-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: hci2 hci_rx_work
task: ffff8881d485c4c0 task.stack: ffff8881d49a8000
RIP: 0010:__list_del_entry_valid.cold.1+0x26/0x4a lib/list_debug.c:45
RSP: 0018:ffff8881d49af7e0 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff8881c5f0b8e8 RCX: 0000000000000000
RDX: 000000000000004e RSI: ffffffff86cbeca0 RDI: ffffed103a935ef3
RBP: ffff8881d49af7f8 R08: ffff8881d485cdb8 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000000 R12: dead000000000200
R13: dead000000000100 R14: ffff8881c9237200 R15: ffff8881c9237280
FS:  0000000000000000(0000) GS:ffff8881f6700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000001bf0608 CR3: 0000000007e6a001 CR4: 00000000001606e0
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: ffff8881d49af7e0
---[ end trace a7c62970fc4676ac ]---