WARNING: locking bug in do_ipv6_setsockopt

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: ff33472c Linux 4.14.134
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15ef21f4600000
kernel config: https://syzkaller.appspot.com/x/.config?x=3559c2b3fb5dd4b2
dashboard link: https://syzkaller.appspot.com/bug?extid=8890bb45d4f6cf5538c3
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16fe653fa00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+8890bb...@syzkaller.appspotmail.com

l2tp_core: tunl 4: sockfd_lookup(fd=5) returned -9
l2tp_core: tunl 4: sockfd_lookup(fd=5) returned -9
------------[ cut here ]------------
WARNING: CPU: 0 PID: 26226 at kernel/locking/lockdep.c:722
arch_local_save_flags arch/x86/include/asm/paravirt.h:773 [inline]
WARNING: CPU: 0 PID: 26226 at kernel/locking/lockdep.c:722
arch_local_save_flags arch/x86/include/asm/paravirt.h:771 [inline]
WARNING: CPU: 0 PID: 26226 at kernel/locking/lockdep.c:722
look_up_lock_class kernel/locking/lockdep.c:713 [inline]
WARNING: CPU: 0 PID: 26226 at kernel/locking/lockdep.c:722
register_lock_class+0xd80/0x1730 kernel/locking/lockdep.c:756
kobject: 'loop5' (ffff8880a4aed3a0): kobject_uevent_env
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 26226 Comm: syz-executor.1 Not tainted 4.14.134 #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x19c lib/dump_stack.c:53
panic+0x1f2/0x426 kernel/panic.c:182
__warn.cold+0x2f/0x36 kernel/panic.c:546
report_bug+0x216/0x254 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:960
RIP: 0010:look_up_lock_class kernel/locking/lockdep.c:722 [inline]
RIP: 0010:register_lock_class+0xd80/0x1730 kernel/locking/lockdep.c:756
RSP: 0018:ffff888096a4f610 EFLAGS: 00010083
RAX: dffffc0000000000 RBX: ffffffff891a66c0 RCX: ffff8880895378e0
RDX: 1ffff110112a6f1f RSI: 1ffffffff11a50d6 RDI: ffff8880895378f8
RBP: ffff888096a4f6d0 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff88cbd5a0 R11: 0000000000000000 R12: ffffffff88d28690
R13: 1ffff11012d49ecd R14: ffffffff86eec1c0 R15: 0000000000000000
kobject: 'loop5' (ffff8880a4aed3a0): fill_kobj_path: path
= '/devices/virtual/block/loop5'
__lock_acquire+0x147/0x45e0 kernel/locking/lockdep.c:3374
kobject: 'loop5' (ffff8880a4aed3a0): kobject_uevent_env
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3991
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x33/0x50 kernel/locking/spinlock.c:176
kobject: 'loop5' (ffff8880a4aed3a0): fill_kobj_path: path
= '/devices/virtual/block/loop5'
spin_lock_bh include/linux/spinlock.h:322 [inline]
lock_sock_nested+0x3f/0x110 net/core/sock.c:2757
lock_sock include/net/sock.h:1462 [inline]
do_ipv6_setsockopt.isra.0+0x20c/0x36d0 net/ipv6/ipv6_sockglue.c:167
kobject: 'loop0' (ffff8880a498c6a0): kobject_uevent_env
kobject: 'loop0' (ffff8880a498c6a0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop5' (ffff8880a4aed3a0): kobject_uevent_env
ipv6_setsockopt+0xd4/0x130 net/ipv6/ipv6_sockglue.c:925
udpv6_setsockopt+0x4e/0x90 net/ipv6/udp.c:1459
sock_common_setsockopt+0x94/0xd0 net/core/sock.c:2963
SYSC_setsockopt net/socket.c:1865 [inline]
SyS_setsockopt+0x13c/0x210 net/socket.c:1844
kobject: 'loop5' (ffff8880a4aed3a0): fill_kobj_path: path
= '/devices/virtual/block/loop5'
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
kobject: 'loop2' (ffff8880a4a369a0): kobject_uevent_env
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459829
RSP: 002b:00007fb21353ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459829
RDX: 0000000000000023 RSI: 0000000000000029 RDI: 0000000000000005
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb21353f6d4
R13: 00000000004ced30 R14: 00000000004dd678 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
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[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: be9b6782 Linux 4.19.60
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=118b7d3fa00000
kernel config: https://syzkaller.appspot.com/x/.config?x=f3bc2d2906e029ec
dashboard link: https://syzkaller.appspot.com/bug?extid=2613d182d8504b952792

compiler: gcc (GCC) 9.0.0 20181231 (experimental)

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10f430cc600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:

Reported-by: syzbot+2613d1...@syzkaller.appspotmail.com

WARNING: CPU: 1 PID: 14568 at kernel/locking/lockdep.c:698
arch_local_save_flags arch/x86/include/asm/paravirt.h:783 [inline]
WARNING: CPU: 1 PID: 14568 at kernel/locking/lockdep.c:698
arch_local_save_flags arch/x86/include/asm/paravirt.h:781 [inline]
WARNING: CPU: 1 PID: 14568 at kernel/locking/lockdep.c:698
look_up_lock_class kernel/locking/lockdep.c:689 [inline]
WARNING: CPU: 1 PID: 14568 at kernel/locking/lockdep.c:698
register_lock_class+0xfeb/0x1cf0 kernel/locking/lockdep.c:748

Kernel panic - not syncing: panic_on_warn set ...

kobject: 'loop5' (000000004e2d52cd): kobject_uevent_env
CPU: 1 PID: 14568 Comm: syz-executor.1 Not tainted 4.19.60 #33

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:

__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
kobject: 'loop5' (000000004e2d52cd): fill_kobj_path: path
= '/devices/virtual/block/loop5'
panic+0x263/0x507 kernel/panic.c:185
__warn.cold+0x20/0x4a kernel/panic.c:540
kobject: 'loop5' (000000004e2d52cd): kobject_uevent_env
report_bug+0x263/0x2b0 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:178 [inline]
fixup_bug arch/x86/kernel/traps.c:173 [inline]
do_error_trap+0x204/0x360 arch/x86/kernel/traps.c:296
kobject: 'loop5' (000000004e2d52cd): fill_kobj_path: path
= '/devices/virtual/block/loop5'
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1035
RIP: 0010:look_up_lock_class kernel/locking/lockdep.c:698 [inline]
RIP: 0010:register_lock_class+0xfeb/0x1cf0 kernel/locking/lockdep.c:748
Code: 60 48 89 da 4d 8b 75 c0 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80
3c 02 00 0f 85 fe 05 00 00 4c 89 33 e9 1b f3 ff ff 0f 0b <0f> 0b e9 0d f2
ff ff 44 89 e0 4c 8b 85 48 ff ff ff 83 c0 01 4c 8b
kobject: 'loop5' (000000004e2d52cd): kobject_uevent_env
RSP: 0018:ffff888082a2f550 EFLAGS: 00010083
RAX: dffffc0000000000 RBX: ffff8880855071a0 RCX: 0000000000000000
RDX: 1ffff11010aa0e37 RSI: 0000000000000000 RDI: ffff8880855071b8
RBP: ffff888082a2f620 R08: 1ffff11010545eb3 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff89eec870
R13: 0000000000000000 R14: ffffffff87dd29c0 R15: dffffc0000000000
kobject: 'loop5' (000000004e2d52cd): fill_kobj_path: path
= '/devices/virtual/block/loop5'
__lock_acquire+0x154/0x48f0 kernel/locking/lockdep.c:3299
kobject: 'loop5' (000000004e2d52cd): kobject_uevent_env
kobject: 'loop5' (000000004e2d52cd): fill_kobj_path: path
= '/devices/virtual/block/loop5'
lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3900
kobject: 'loop5' (000000004e2d52cd): kobject_uevent_env
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x33/0x50 kernel/locking/spinlock.c:168
spin_lock_bh include/linux/spinlock.h:334 [inline]
lock_sock_nested+0x41/0x120 net/core/sock.c:2833
lock_sock include/net/sock.h:1501 [inline]
do_ipv6_setsockopt.isra.0+0x273/0x3eb0 net/ipv6/ipv6_sockglue.c:167
kobject: 'loop5' (000000004e2d52cd): fill_kobj_path: path
= '/devices/virtual/block/loop5'
kobject: 'loop0' (000000005cfbfc7f): kobject_uevent_env
kobject: 'loop0' (000000005cfbfc7f): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop5' (000000004e2d52cd): kobject_uevent_env
kobject: 'loop5' (000000004e2d52cd): fill_kobj_path: path
= '/devices/virtual/block/loop5'
kobject: 'loop0' (000000005cfbfc7f): kobject_uevent_env
kobject: 'loop0' (000000005cfbfc7f): fill_kobj_path: path
= '/devices/virtual/block/loop0'
ipv6_setsockopt+0xf6/0x170 net/ipv6/ipv6_sockglue.c:933
udpv6_setsockopt+0x68/0xb0 net/ipv6/udp.c:1492
sock_common_setsockopt+0x94/0xd0 net/core/sock.c:3041
__sys_setsockopt+0x17a/0x280 net/socket.c:1901
kobject: 'loop4' (00000000198c32a5): kobject_uevent_env
__do_sys_setsockopt net/socket.c:1912 [inline]
__se_sys_setsockopt net/socket.c:1909 [inline]
__x64_sys_setsockopt+0xbe/0x150 net/socket.c:1909
do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
kobject: 'loop4' (00000000198c32a5): fill_kobj_path: path
= '/devices/virtual/block/loop4'
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f80c1378c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036

RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459829

RDX: 0000000000000023 RSI: 0000000000000029 RDI: 0000000000000006
kobject: 'loop2' (0000000028a5eabb): kobject_uevent_env

RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 00007f80c13796d4