• Eric Dumazet's avatar
    ax25: fix inconsistent lock state in ax25_destroy_timer · d4d5d8e8
    Eric Dumazet authored
    Before thread in process context uses bh_lock_sock()
    we must disable bh.
    
    sysbot reported :
    
    WARNING: inconsistent lock state
    5.2.0-rc3+ #32 Not tainted
    
    inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
    blkid/26581 [HC0[0]:SC1[1]:HE1:SE0] takes:
    00000000e0da85ee (slock-AF_AX25){+.?.}, at: spin_lock include/linux/spinlock.h:338 [inline]
    00000000e0da85ee (slock-AF_AX25){+.?.}, at: ax25_destroy_timer+0x53/0xc0 net/ax25/af_ax25.c:275
    {SOFTIRQ-ON-W} state was registered at:
      lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
      __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
      _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
      spin_lock include/linux/spinlock.h:338 [inline]
      ax25_rt_autobind+0x3ca/0x720 net/ax25/ax25_route.c:429
      ax25_connect.cold+0x30/0xa4 net/ax25/af_ax25.c:1221
      __sys_connect+0x264/0x330 net/socket.c:1834
      __do_sys_connect net/socket.c:1845 [inline]
      __se_sys_connect net/socket.c:1842 [inline]
      __x64_sys_connect+0x73/0xb0 net/socket.c:1842
      do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
      entry_SYSCALL_64_after_hwframe+0x49/0xbe
    irq event stamp: 2272
    hardirqs last  enabled at (2272): [<ffffffff810065f3>] trace_hardirqs_on_thunk+0x1a/0x1c
    hardirqs last disabled at (2271): [<ffffffff8100660f>] trace_hardirqs_off_thunk+0x1a/0x1c
    softirqs last  enabled at (1522): [<ffffffff87400654>] __do_softirq+0x654/0x94c kernel/softirq.c:320
    softirqs last disabled at (2267): [<ffffffff81449010>] invoke_softirq kernel/softirq.c:374 [inline]
    softirqs last disabled at (2267): [<ffffffff81449010>] irq_exit+0x180/0x1d0 kernel/softirq.c:414
    
    other info that might help us debug this:
     Possible unsafe locking scenario:
    
           CPU0
           ----
      lock(slock-AF_AX25);
      <Interrupt>
        lock(slock-AF_AX25);
    
     *** DEADLOCK ***
    
    1 lock held by blkid/26581:
     #0: 0000000010fd154d ((&ax25->dtimer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:175 [inline]
     #0: 0000000010fd154d ((&ax25->dtimer)){+.-.}, at: call_timer_fn+0xe0/0x720 kernel/time/timer.c:1312
    
    stack backtrace:
    CPU: 1 PID: 26581 Comm: blkid Not tainted 5.2.0-rc3+ #32
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
    Call Trace:
     <IRQ>
     __dump_stack lib/dump_stack.c:77 [inline]
     dump_stack+0x172/0x1f0 lib/dump_stack.c:113
     print_usage_bug.cold+0x393/0x4a2 kernel/locking/lockdep.c:2935
     valid_state kernel/locking/lockdep.c:2948 [inline]
     mark_lock_irq kernel/locking/lockdep.c:3138 [inline]
     mark_lock+0xd46/0x1370 kernel/locking/lockdep.c:3513
     mark_irqflags kernel/locking/lockdep.c:3391 [inline]
     __lock_acquire+0x159f/0x5490 kernel/locking/lockdep.c:3745
     lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4303
     __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
     _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
     spin_lock include/linux/spinlock.h:338 [inline]
     ax25_destroy_timer+0x53/0xc0 net/ax25/af_ax25.c:275
     call_timer_fn+0x193/0x720 kernel/time/timer.c:1322
     expire_timers kernel/time/timer.c:1366 [inline]
     __run_timers kernel/time/timer.c:1685 [inline]
     __run_timers kernel/time/timer.c:1653 [inline]
     run_timer_softirq+0x66f/0x1740 kernel/time/timer.c:1698
     __do_softirq+0x25c/0x94c kernel/softirq.c:293
     invoke_softirq kernel/softirq.c:374 [inline]
     irq_exit+0x180/0x1d0 kernel/softirq.c:414
     exiting_irq arch/x86/include/asm/apic.h:536 [inline]
     smp_apic_timer_interrupt+0x13b/0x550 arch/x86/kernel/apic/apic.c:1068
     apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806
     </IRQ>
    RIP: 0033:0x7f858d5c3232
    Code: 8b 61 08 48 8b 84 24 d8 00 00 00 4c 89 44 24 28 48 8b ac 24 d0 00 00 00 4c 8b b4 24 e8 00 00 00 48 89 7c 24 68 48 89 4c 24 78 <48> 89 44 24 58 8b 84 24 e0 00 00 00 89 84 24 84 00 00 00 8b 84 24
    RSP: 002b:00007ffcaf0cf5c0 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
    RAX: 00007f858d7d27a8 RBX: 00007f858d7d8820 RCX: 00007f858d3940d8
    RDX: 00007ffcaf0cf798 RSI: 00000000f5e616f3 RDI: 00007f858d394fee
    RBP: 0000000000000000 R08: 00007ffcaf0cf780 R09: 00007f858d7db480
    R10: 0000000000000000 R11: 0000000009691a75 R12: 0000000000000005
    R13: 00000000f5e616f3 R14: 0000000000000000 R15: 00007ffcaf0cf798
    Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
    Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    d4d5d8e8
ax25_route.c 10.7 KB