bisecting fixing commit since c076c79e03c6094e578df5d210fde808b3ad32e6
building syzkaller on 4ca1c0ea446d2c09b1fb49a85ae645e3754f1058
testing commit c076c79e03c6094e578df5d210fde808b3ad32e6 with gcc (GCC) 8.1.0
kernel signature: 0603cf773e47fa505c174c17d8baa71d92f748b420cf6715c80809af512fed8d
all runs: crashed: BUG: corrupted list in l2cap_chan_put
testing current HEAD b09c34517e1ac4018e3bb75ed5c8610a8a1f486b
testing commit b09c34517e1ac4018e3bb75ed5c8610a8a1f486b with gcc (GCC) 8.1.0
kernel signature: e339d9d667eaa66e16acd3d9bf108610cd5afd58cba7a5621c2d651c6a2a93c2
run #0: crashed: KASAN: use-after-free Write in init_timer_key
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
revisions tested: 2, total time: 34m56.795319366s (build: 18m9.059793833s, test: 15m59.173402635s)
the crash still happens on HEAD
commit msg: Linux 4.19.149
crash: BUG: corrupted list in l2cap_chan_put
Bluetooth: hci3: command 0x0419 tx timeout
Bluetooth: hci5: command 0x0419 tx timeout
Bluetooth: hci4: command 0x0419 tx timeout
list_del corruption, ffff8880a17e5888->next is LIST_POISON1 (dead000000000100)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:47!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 13877 Comm: syz-executor898 Not tainted 4.19.149-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_del_entry_valid.cold.1+0x26/0x58 lib/list_debug.c:45
Code: 1d fe 0f 0b 4c 89 e2 48 89 de 48 c7 c7 20 8c 67 87 e8 06 a7 1d fe 0f 0b 4c 89 ea 48 89 de 48 c7 c7 c0 8b 67 87 e8 f2 a6 1d fe <0f> 0b 48 89 de 48 c7 c7 e0 8c 67 87 e8 e1 a6 1d fe 0f 0b 48 89 de
RSP: 0018:ffff888071c0fd28 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff8880a17e5888 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff87678920 RDI: ffffffff8a1a6a60
RBP: ffff888071c0fd40 R08: ffffed1015d45081 R09: ffffed1015d45080
R10: ffffed1015d45080 R11: ffff8880aea28407 R12: dead000000000200
R13: dead000000000100 R14: 0000000000000000 R15: ffff888086820fa0
FS:  0000000002419880(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000180 CR3: 00000000a41cc000 CR4: 00000000001406f0
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+0x1c1/0x240 net/bluetooth/l2cap_sock.c:1212
 __sock_release+0xc2/0x290 net/socket.c:579
 sock_close+0x10/0x20 net/socket.c:1140
 __fput+0x249/0x7f0 fs/file_table.c:278
 ____fput+0x9/0x10 fs/file_table.c:309
 task_work_run+0x108/0x180 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x185/0x1e0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x408821
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 24 1a 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007ffecb7a11a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000408821
RDX: fffffffffffffff7 RSI: 0000000000000080 RDI: 0000000000000004
RBP: 00007ffecb7a1240 R08: 0000000000000000 R09: 0000000000000000
R10: 00007ffecb7a11f0 R11: 0000000000000293 R12: 00000000006dfc20
R13: 0000000000000003 R14: 00000000006dfc2c R15: 0000000000000000
Modules linked in:
---[ end trace 1e37121f7ac1157b ]---
RIP: 0010:__list_del_entry_valid.cold.1+0x26/0x58 lib/list_debug.c:45
Code: 1d fe 0f 0b 4c 89 e2 48 89 de 48 c7 c7 20 8c 67 87 e8 06 a7 1d fe 0f 0b 4c 89 ea 48 89 de 48 c7 c7 c0 8b 67 87 e8 f2 a6 1d fe <0f> 0b 48 89 de 48 c7 c7 e0 8c 67 87 e8 e1 a6 1d fe 0f 0b 48 89 de
RSP: 0018:ffff888071c0fd28 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff8880a17e5888 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff87678920 RDI: ffffffff8a1a6a60
RBP: ffff888071c0fd40 R08: ffffed1015d45081 R09: ffffed1015d45080
R10: ffffed1015d45080 R11: ffff8880aea28407 R12: dead000000000200
R13: dead000000000100 R14: 0000000000000000 R15: ffff888086820fa0
FS:  0000000002419880(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000180 CR3: 00000000a41cc000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400