bisecting fixing commit since 14b58326976de6ef3998eefec1dd7f8b38b97a75
building syzkaller on ff51e5229e0ee846d2fd687cb0dbca13de758c66
testing commit 14b58326976de6ef3998eefec1dd7f8b38b97a75 with gcc (GCC) 8.4.1 20210217
kernel signature: f2ababd395cedef4b52f533fd7b3ca429defd6b54366d1a330108214e423ca9c
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: BUG: corrupted list in l2cap_chan_put
run #13: crashed: KASAN: use-after-free Read 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 cf256fbcbe347b7d0ff58fe2dfa382a156bd3694
testing commit cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 with gcc (GCC) 8.4.1 20210217
kernel signature: 81abd9bcc5266368127d47727e4b0a64bf8e9adf2d2faddaafeebb053f8aed87
run #0: crashed: BUG: corrupted list in l2cap_chan_put
run #1: crashed: BUG: corrupted list in l2cap_chan_put
run #2: crashed: KASAN: use-after-free Read 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
revisions tested: 2, total time: 35m45.43894047s (build: 16m56.648271833s, test: 18m25.086232959s)
the crash still happens on HEAD
commit msg: Linux 4.14.231
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, ffff8881dc8a17a8->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: 5718 Comm: syz-executor395 Not tainted 4.14.231-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8881e809a500 task.stack: ffff8881f41e0000
RIP: 0010:__list_del_entry_valid.cold.1+0x26/0x4a lib/list_debug.c:45
RSP: 0018:ffff8881f41e7cf8 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff8881dc8a17a8 RCX: 0000000000000000
RDX: 000000000000004e RSI: ffffffff86cbeca0 RDI: ffffed103e83cf96
RBP: ffff8881f41e7d10 R08: ffff8881e809add0 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000000 R12: dead000000000200
R13: dead000000000100 R14: ffff8881dc8a17c8 R15: ffff8881dae64c20
FS:  0000000001977300(0000) GS:ffff8881f6600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000180 CR3: 00000001e5095001 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_sock_release+0x1b4/0x230 net/bluetooth/l2cap_sock.c:1213
 __sock_release+0xc2/0x2a0 net/socket.c:602
 sock_close+0x10/0x20 net/socket.c:1139
 __fput+0x232/0x740 fs/file_table.c:210
 ____fput+0x9/0x10 fs/file_table.c:244
 task_work_run+0xe5/0x170 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x14a/0x190 arch/x86/entry/common.c:164
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x416/0x5b0 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x406dcb
RSP: 002b:00007ffea8a28ee0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000406dcb
RDX: ffffffffffffffb8 RSI: 0000000020000180 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffea8a28f40
R13: 00007ffea8a28f30 R14: 0000000000063f5f R15: 00007ffea8a28f08
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: ffff8881f41e7cf8
---[ end trace 6fb23290628b7a94 ]---