syzbot

netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0
======================================================
WARNING: possible circular locking dependency detected
6.1.135-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor345/4247 is trying to acquire lock:
ffff88802f850910 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: __flush_work+0xd4/0xa60 kernel/workqueue.c:3072

but task is already holding lock:
ffff8880773f8130 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x251/0x530 net/smc/af_smc.c:-1

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (sk_lock-AF_SMC/1){+.+.}-{0:0}:
       lock_sock_nested+0x44/0x100 net/core/sock.c:3488
       smc_listen_out+0x109/0x3d0 net/smc/af_smc.c:1865
       process_one_work+0x898/0x1160 kernel/workqueue.c:2292
       worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
       kthread+0x29d/0x330 kernel/kthread.c:376
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

-> #0 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049
       lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
       __flush_work+0xed/0xa60 kernel/workqueue.c:3072
       __cancel_work_timer+0x3ac/0x520 kernel/workqueue.c:3163
       smc_clcsock_release+0x5c/0xe0 net/smc/smc_close.c:29
       __smc_release+0x661/0x7d0 net/smc/af_smc.c:300
       smc_close_non_accepted+0xd1/0x1f0 net/smc/af_smc.c:1798
       smc_close_cleanup_listen net/smc/smc_close.c:45 [inline]
       smc_close_active+0xb00/0xea0 net/smc/smc_close.c:225
       __smc_release+0x8d/0x7d0 net/smc/af_smc.c:276
       smc_release+0x2ca/0x530 net/smc/af_smc.c:343
       __sock_release net/socket.c:654 [inline]
       sock_close+0xd5/0x240 net/socket.c:1400
       __fput+0x22c/0x920 fs/file_table.c:320
       task_work_run+0x1ca/0x250 kernel/task_work.c:203
       exit_task_work include/linux/task_work.h:39 [inline]
       do_exit+0x936/0x2400 kernel/exit.c:871
       do_group_exit+0x217/0x2d0 kernel/exit.c:1021
       __do_sys_exit_group kernel/exit.c:1032 [inline]
       __se_sys_exit_group kernel/exit.c:1030 [inline]
       __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1030
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(sk_lock-AF_SMC/1);
                               lock((work_completion)(&new_smc->smc_listen_work));
                               lock(sk_lock-AF_SMC/1);
  lock((work_completion)(&new_smc->smc_listen_work));

 *** DEADLOCK ***

2 locks held by syz-executor345/4247:
 #0: ffff888072779410 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #0: ffff888072779410 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline]
 #0: ffff888072779410 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1400
 #1: ffff8880773f8130 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x251/0x530 net/smc/af_smc.c:-1

stack backtrace:
CPU: 1 PID: 4247 Comm: syz-executor345 Not tainted 6.1.135-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain kernel/locking/lockdep.c:3825 [inline]
 __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 __flush_work+0xed/0xa60 kernel/workqueue.c:3072
 __cancel_work_timer+0x3ac/0x520 kernel/workqueue.c:3163
 smc_clcsock_release+0x5c/0xe0 net/smc/smc_close.c:29
 __smc_release+0x661/0x7d0 net/smc/af_smc.c:300
 smc_close_non_accepted+0xd1/0x1f0 net/smc/af_smc.c:1798
 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline]
 smc_close_active+0xb00/0xea0 net/smc/smc_close.c:225
 __smc_release+0x8d/0x7d0 net/smc/af_smc.c:276
 smc_release+0x2ca/0x530 net/smc/af_smc.c:343
 __sock_release net/socket.c:654 [inline]
 sock_close+0xd5/0x240 net/socket.c:1400
 __fput+0x22c/0x920 fs/file_table.c:320
 task_work_run+0x1ca/0x250 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0x936/0x2400 kernel/exit.c:871
 do_group_exit+0x217/0x2d0 kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1030
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f594b9c78e9
Code: Unable to access opcode bytes at 0x7f594b9c78bf.
RSP: 002b:00007fff6de6d728 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f594b9c78e9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 00007f594ba47390 R08: ffffffffffffffb8 R09: 0