[v6.6] inconsistent lock state in valid_state

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 9760bf04666d Linux 6.6.135
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16fdc1ba580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c5b35c4db8465904
dashboard link: https://syzkaller.appspot.com/bug?extid=939326ce26153c515dc2
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a685913d05a7/disk-9760bf04.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a3c1d21d4bca/vmlinux-9760bf04.xz
kernel image: https://storage.googleapis.com/syzbot-assets/09178887ef0d/bzImage-9760bf04.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+939326...@syzkaller.appspotmail.com

================================
WARNING: inconsistent lock state
syzkaller #0 Not tainted
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
syz.0.45/6214 [HC0[0]:SC1[1]:HE1:SE0] takes:
ffff888023cb80b0 (slock-AF_PHONET/1){+.?.}-{2:2}, at: __sk_receive_skb+0x180/0x990 net/core/sock.c:564
{SOFTIRQ-ON-W} state was registered at:
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
_raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:378
__sk_receive_skb+0x180/0x990 net/core/sock.c:564
sk_receive_skb include/net/sock.h:2071 [inline]
pep_do_rcv+0x682/0xa90 net/phonet/pep.c:675
sk_backlog_rcv include/net/sock.h:1142 [inline]
__release_sock+0x1e5/0x460 net/core/sock.c:3011
release_sock+0x5f/0x1c0 net/core/sock.c:3550
pep_sock_accept+0xd58/0x12d0 net/phonet/pep.c:879
pn_socket_accept+0x12a/0x370 net/phonet/socket.c:304
do_accept+0x4d8/0x6c0 net/socket.c:1937
__sys_accept4_file net/socket.c:1977 [inline]
__sys_accept4+0x9b/0x100 net/socket.c:2007
__do_sys_accept4 net/socket.c:2018 [inline]
__se_sys_accept4 net/socket.c:2015 [inline]
__x64_sys_accept4+0x9a/0xb0 net/socket.c:2015
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
irq event stamp: 120
hardirqs last enabled at (120): [<ffffffff8a8ff4f3>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]
hardirqs last enabled at (120): [<ffffffff8a8ff4f3>] _raw_spin_unlock_irq+0x23/0x50 kernel/locking/spinlock.c:202
hardirqs last disabled at (119): [<ffffffff8a8ff2ba>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline]
hardirqs last disabled at (119): [<ffffffff8a8ff2ba>] _raw_spin_lock_irq+0x8a/0xf0 kernel/locking/spinlock.c:170
softirqs last enabled at (114): [<ffffffff8879e2f9>] local_bh_enable include/linux/bottom_half.h:33 [inline]
softirqs last enabled at (114): [<ffffffff8879e2f9>] netif_rx+0x79/0x90 net/core/dev.c:5232
softirqs last disabled at (115): [<ffffffff8152678a>] do_softirq+0xfa/0x1a0 kernel/softirq.c:479

other info that might help us debug this:
Possible unsafe locking scenario:

CPU0
----
lock(slock-AF_PHONET/1);
<Interrupt>
lock(slock-AF_PHONET/1);

*** DEADLOCK ***

4 locks held by syz.0.45/6214:
#0: ffff88805bd50770 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88805bd50770 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: sk_stream_wait_connect+0x452/0x820 net/core/stream.c:75
#1: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#1: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#1: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x2cf/0x6f0 net/core/dev.c:6087
#2: ffff88805bd500b0 (slock-AF_PHONET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff88805bd500b0 (slock-AF_PHONET){+.-.}-{2:2}, at: __sk_receive_skb+0x18f/0x990 net/core/sock.c:566
#3: ffff88805bd50130 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: sk_receive_skb include/net/sock.h:2071 [inline]
#3: ffff88805bd50130 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: phonet_rcv+0x78f/0xc80 net/phonet/af_phonet.c:-1

stack backtrace:
CPU: 1 PID: 6214 Comm: syz.0.45 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
<IRQ>
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
valid_state+0x13b/0x1d0 kernel/locking/lockdep.c:4013
mark_lock_irq+0xad/0x900 kernel/locking/lockdep.c:4216
mark_lock+0x208/0x320 kernel/locking/lockdep.c:4678
mark_usage kernel/locking/lockdep.c:-1 [inline]
__lock_acquire+0xd1a/0x7d40 kernel/locking/lockdep.c:5091
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
_raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:378
__sk_receive_skb+0x180/0x990 net/core/sock.c:564
sk_receive_skb include/net/sock.h:2071 [inline]
pep_do_rcv+0x682/0xa90 net/phonet/pep.c:675
sk_backlog_rcv include/net/sock.h:1142 [inline]
__sk_receive_skb+0x436/0x990 net/core/sock.c:573
sk_receive_skb include/net/sock.h:2071 [inline]
phonet_rcv+0x78f/0xc80 net/phonet/af_phonet.c:-1
__netif_receive_skb_one_core net/core/dev.c:5646 [inline]
__netif_receive_skb+0xcc/0x290 net/core/dev.c:5760
process_backlog+0x391/0x6f0 net/core/dev.c:6088
__napi_poll+0xc0/0x460 net/core/dev.c:6650
napi_poll net/core/dev.c:6717 [inline]
net_rx_action+0x616/0xc40 net/core/dev.c:6853
handle_softirqs+0x280/0x820 kernel/softirq.c:578
do_softirq+0xfa/0x1a0 kernel/softirq.c:479
</IRQ>
<TASK>
__local_bh_enable_ip+0x184/0x1c0 kernel/softirq.c:406
local_bh_enable include/linux/bottom_half.h:33 [inline]
netif_rx+0x83/0x90 net/core/dev.c:5232
pn_send+0x553/0x7f0 net/phonet/af_phonet.c:185
pn_skb_send+0x218/0x510 net/phonet/af_phonet.c:272
pipe_skb_send+0x2d7/0x500 net/phonet/pep.c:1129
pep_sendmsg+0x9aa/0xad0 net/phonet/pep.c:1205
pn_socket_sendmsg+0x1df/0x240 net/phonet/socket.c:425
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
sock_write_iter+0x2df/0x420 net/socket.c:1160
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x46c/0x990 fs/read_write.c:584
ksys_write+0x150/0x260 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7b7e19c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7b7ef75028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7b7e416090 RCX: 00007f7b7e19c819
RDX: 00000000000003db RSI: 0000200000000480 RDI: 0000000000000006
RBP: 00007f7b7e232c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7b7e416128 R14: 00007f7b7e416090 R15: 00007ffd15fe2d98
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 9760bf04666d Linux 6.6.135
git tree: linux-6.6.y

console output: https://syzkaller.appspot.com/x/log.txt?x=11c342d2580000

kernel config: https://syzkaller.appspot.com/x/.config?x=c5b35c4db8465904
dashboard link: https://syzkaller.appspot.com/bug?extid=939326ce26153c515dc2
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11f91702580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16330836580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a685913d05a7/disk-9760bf04.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a3c1d21d4bca/vmlinux-9760bf04.xz
kernel image: https://storage.googleapis.com/syzbot-assets/09178887ef0d/bzImage-9760bf04.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+939326...@syzkaller.appspotmail.com

================================
WARNING: inconsistent lock state
syzkaller #0 Not tainted
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.

syz.0.17/5918 [HC0[0]:SC1[1]:HE1:SE0] takes:
ffff888029d880b0 (slock-AF_PHONET/1){+.?.}-{2:2}, at: __sk_receive_skb+0x180/0x990 net/core/sock.c:564

{SOFTIRQ-ON-W} state was registered at:
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
_raw_spin_lock_nested+0x32/0x50 kernel/locking/spinlock.c:378
__sk_receive_skb+0x180/0x990 net/core/sock.c:564
sk_receive_skb include/net/sock.h:2071 [inline]
pep_do_rcv+0x682/0xa90 net/phonet/pep.c:675
sk_backlog_rcv include/net/sock.h:1142 [inline]
__release_sock+0x1e5/0x460 net/core/sock.c:3011
release_sock+0x5f/0x1c0 net/core/sock.c:3550
pep_sock_accept+0xd58/0x12d0 net/phonet/pep.c:879
pn_socket_accept+0x12a/0x370 net/phonet/socket.c:304
do_accept+0x4d8/0x6c0 net/socket.c:1937
__sys_accept4_file net/socket.c:1977 [inline]
__sys_accept4+0x9b/0x100 net/socket.c:2007
__do_sys_accept4 net/socket.c:2018 [inline]
__se_sys_accept4 net/socket.c:2015 [inline]
__x64_sys_accept4+0x9a/0xb0 net/socket.c:2015
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2

irq event stamp: 106
hardirqs last enabled at (106): [<ffffffff8a8ff4f3>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]
hardirqs last enabled at (106): [<ffffffff8a8ff4f3>] _raw_spin_unlock_irq+0x23/0x50 kernel/locking/spinlock.c:202
hardirqs last disabled at (105): [<ffffffff8a8ff2ba>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline]
hardirqs last disabled at (105): [<ffffffff8a8ff2ba>] _raw_spin_lock_irq+0x8a/0xf0 kernel/locking/spinlock.c:170
softirqs last enabled at (100): [<ffffffff8879e2f9>] local_bh_enable include/linux/bottom_half.h:33 [inline]
softirqs last enabled at (100): [<ffffffff8879e2f9>] netif_rx+0x79/0x90 net/core/dev.c:5232
softirqs last disabled at (101): [<ffffffff8152678a>] do_softirq+0xfa/0x1a0 kernel/softirq.c:479

other info that might help us debug this:
Possible unsafe locking scenario:

CPU0
----
lock(slock-AF_PHONET/1);
<Interrupt>
lock(slock-AF_PHONET/1);

*** DEADLOCK ***

4 locks held by syz.0.17/5918:
#0: ffff88802a688770 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff88802a688770 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: pep_sendmsg+0x799/0xad0 net/phonet/pep.c:1198

#1: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#1: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#1: ffffffff8d1320e0 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x2cf/0x6f0 net/core/dev.c:6087

#2: ffff88802a6880b0 (slock-AF_PHONET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff88802a6880b0 (slock-AF_PHONET){+.-.}-{2:2}, at: __sk_receive_skb+0x18f/0x990 net/core/sock.c:566
#3: ffff88802a688130 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: sk_receive_skb include/net/sock.h:2071 [inline]
#3: ffff88802a688130 (sk_lock-AF_PHONET){+.+.}-{0:0}, at: phonet_rcv+0x78f/0xc80 net/phonet/af_phonet.c:-1

stack backtrace:
CPU: 0 PID: 5918 Comm: syz.0.17 Not tainted syzkaller #0

RIP: 0033:0x7f4d3039c819

Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48

RSP: 002b:00007f4d311ae028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f4d30616090 RCX: 00007f4d3039c819

RDX: 00000000000003db RSI: 0000200000000480 RDI: 0000000000000006

RBP: 00007f4d30432c91 R08: 0000000000000000 R09: 0000000000000000

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000

R13: 00007f4d30616128 R14: 00007f4d30616090 R15: 00007ffff630e2d8
</TASK>


---
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