======================================================== WARNING: possible irq lock inversion dependency detected 5.14.0-rc6-syzkaller #0 Not tainted -------------------------------------------------------- syz-executor.5/26814 just changed the state of lock: ffff8880644210c0 (&new->fa_lock){.+..}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1012 [inline] ffff8880644210c0 (&new->fa_lock){.+..}-{2:2}, at: kill_fasync fs/fcntl.c:1033 [inline] ffff8880644210c0 (&new->fa_lock){.+..}-{2:2}, at: kill_fasync+0x132/0x460 fs/fcntl.c:1026 but this lock was taken by another, HARDIRQ-safe lock in the past: (&timer->lock){-.-.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&new->fa_lock); local_irq_disable(); lock(&timer->lock); lock(&new->fa_lock); lock(&timer->lock); *** DEADLOCK *** 5 locks held by syz-executor.5/26814: #0: ffff88801da7bbe0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1613 [inline] #0: ffff88801da7bbe0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: mptcp_stream_connect+0x85/0x9d0 net/mptcp/protocol.c:3129 #1: ffff88801da7bb60 (slock-AF_INET6){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:359 [inline] #1: ffff88801da7bb60 (slock-AF_INET6){+.-.}-{2:2}, at: release_sock+0x1b/0x1b0 net/core/sock.c:3177 #2: ffffffff8b97c280 (rcu_read_lock){....}-{1:2}, at: sock_def_error_report+0x0/0x4e0 include/net/sock.h:2327 #3: ffffffff8b97c280 (rcu_read_lock){....}-{1:2}, at: rcu_read_unlock include/linux/rcupdate.h:716 [inline] #3: ffffffff8b97c280 (rcu_read_lock){....}-{1:2}, at: sock_def_error_report+0x2af/0x4e0 net/core/sock.c:3005 #4: ffffffff8b97c280 (rcu_read_lock){....}-{1:2}, at: kill_fasync+0x3d/0x460 fs/fcntl.c:1031 the shortest dependencies between 2nd lock and 1st lock: -> (&timer->lock){-.-.}-{2:2} { IN-HARDIRQ-W at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] snd_hrtimer_callback+0x4f/0x3c0 sound/core/hrtimer.c:38 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1601 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1106 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 lockdep_enabled kernel/locking/lockdep.c:85 [inline] lock_release+0xe0/0x720 kernel/locking/lockdep.c:5638 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:174 [inline] _raw_spin_unlock_bh+0x12/0x30 kernel/locking/spinlock.c:207 spin_unlock_bh include/linux/spinlock.h:399 [inline] batadv_nc_purge_paths+0x2a5/0x3a0 net/batman-adv/network-coding.c:467 batadv_nc_worker+0x7ff/0xe50 net/batman-adv/network-coding.c:716 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] snd_hrtimer_callback+0x4f/0x3c0 sound/core/hrtimer.c:38 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1601 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1106 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 unwind_next_frame+0x148e/0x1ce0 arch/x86/kernel/unwind_orc.c:604 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x84/0xa0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] kmem_cache_alloc_bulk+0x1ec/0x490 mm/slub.c:3423 napi_skb_cache_get+0xeb/0x170 net/core/skbuff.c:177 __alloc_skb+0x9a/0x340 net/core/skbuff.c:412 __napi_alloc_skb+0x70/0x310 net/core/skbuff.c:567 napi_alloc_skb include/linux/skbuff.h:2929 [inline] page_to_skb+0x1b3/0xc60 drivers/net/virtio_net.c:442 receive_mergeable drivers/net/virtio_net.c:1031 [inline] receive_buf+0x338e/0x6380 drivers/net/virtio_net.c:1141 virtnet_receive drivers/net/virtio_net.c:1433 [inline] virtnet_poll+0x5bf/0x11c0 drivers/net/virtio_net.c:1542 __napi_poll+0xaf/0x440 net/core/dev.c:7047 napi_poll net/core/dev.c:7114 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7201 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 do_softirq.part.0+0xde/0x130 kernel/softirq.c:459 do_softirq kernel/softirq.c:451 [inline] __local_bh_enable_ip+0x102/0x120 kernel/softirq.c:383 local_bh_enable include/linux/bottom_half.h:32 [inline] ipt_do_table+0xd29/0x1970 net/ipv4/netfilter/ip_tables.c:358 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xc5/0x1e0 net/netfilter/core.c:589 nf_hook+0x1cb/0x5b0 include/linux/netfilter.h:262 __ip_local_out+0x26e/0x530 net/ipv4/ip_output.c:115 ip_local_out net/ipv4/ip_output.c:124 [inline] __ip_queue_xmit+0x848/0x1a30 net/ipv4/ip_output.c:533 __tcp_transmit_skb+0x1891/0x3900 net/ipv4/tcp_output.c:1405 tcp_transmit_skb net/ipv4/tcp_output.c:1423 [inline] tcp_write_xmit+0xdee/0x6030 net/ipv4/tcp_output.c:2690 __tcp_push_pending_frames+0xaa/0x390 net/ipv4/tcp_output.c:2874 tcp_push+0x44d/0x6d0 net/ipv4/tcp.c:736 tcp_sendmsg_locked+0x2514/0x2f10 net/ipv4/tcp.c:1431 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1461 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:821 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:723 sock_write_iter+0x289/0x3c0 net/socket.c:1056 call_write_iter include/linux/fs.h:2114 [inline] new_sync_write+0x426/0x650 fs/read_write.c:518 vfs_write+0x75a/0xa40 fs/read_write.c:605 ksys_write+0x1ee/0x250 fs/read_write.c:658 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:159 snd_timer_notify sound/core/timer.c:1087 [inline] snd_timer_notify+0x10c/0x3d0 sound/core/timer.c:1074 snd_pcm_timer_notify sound/core/pcm_native.c:590 [inline] snd_pcm_post_stop+0x195/0x1f0 sound/core/pcm_native.c:1448 snd_pcm_action_single sound/core/pcm_native.c:1224 [inline] snd_pcm_action+0x143/0x170 sound/core/pcm_native.c:1305 snd_pcm_stop sound/core/pcm_native.c:1471 [inline] snd_pcm_drop+0x1ab/0x320 sound/core/pcm_native.c:2150 snd_pcm_kernel_ioctl+0x12f/0x240 sound/core/pcm_native.c:3362 snd_pcm_oss_sync+0x230/0x800 sound/core/oss/pcm_oss.c:1721 snd_pcm_oss_release+0x276/0x300 sound/core/oss/pcm_oss.c:2571 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] __key.12+0x0/0x40 ... acquired at: __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1012 [inline] kill_fasync fs/fcntl.c:1033 [inline] kill_fasync+0x132/0x460 fs/fcntl.c:1026 snd_timer_user_ccallback+0x298/0x330 sound/core/timer.c:1387 snd_timer_notify1+0x11c/0x3b0 sound/core/timer.c:516 snd_timer_start1+0x4d4/0x800 sound/core/timer.c:578 snd_timer_start sound/core/timer.c:697 [inline] snd_timer_start sound/core/timer.c:690 [inline] snd_timer_user_start.isra.0+0x1e3/0x260 sound/core/timer.c:1985 __snd_timer_user_ioctl.isra.0+0xda8/0x24c0 sound/core/timer.c:2108 snd_timer_user_ioctl+0x77/0xb0 sound/core/timer.c:2129 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> (&new->fa_lock){.+..}-{2:2} { HARDIRQ-ON-R at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x36/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1012 [inline] kill_fasync fs/fcntl.c:1033 [inline] kill_fasync+0x132/0x460 fs/fcntl.c:1026 sock_wake_async+0xd2/0x160 net/socket.c:1354 sk_wake_async include/net/sock.h:2327 [inline] sk_wake_async include/net/sock.h:2323 [inline] sock_def_error_report+0x34b/0x4e0 net/core/sock.c:3004 sk_error_report+0x35/0x310 net/core/sock.c:338 __mptcp_error_report+0x25d/0x2f0 net/mptcp/subflow.c:1240 mptcp_release_cb+0x1cc/0x210 net/mptcp/protocol.c:2909 release_sock+0xb4/0x1b0 net/core/sock.c:3185 mptcp_stream_connect+0x243/0x9d0 net/mptcp/protocol.c:3174 __sys_connect_file+0x155/0x1a0 net/socket.c:1879 __sys_connect+0x161/0x190 net/socket.c:1896 __do_sys_connect net/socket.c:1906 [inline] __se_sys_connect net/socket.c:1903 [inline] __x64_sys_connect+0x6f/0xb0 net/socket.c:1903 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_write_lock_irq include/linux/rwlock_api_smp.h:196 [inline] _raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:311 fasync_remove_entry+0xb6/0x1f0 fs/fcntl.c:890 fasync_helper+0x9e/0xb0 fs/fcntl.c:993 __fput+0x712/0x920 fs/file_table.c:277 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1012 [inline] kill_fasync fs/fcntl.c:1033 [inline] kill_fasync+0x132/0x460 fs/fcntl.c:1026 snd_timer_user_ccallback+0x298/0x330 sound/core/timer.c:1387 snd_timer_notify1+0x11c/0x3b0 sound/core/timer.c:516 snd_timer_start1+0x4d4/0x800 sound/core/timer.c:578 snd_timer_start sound/core/timer.c:697 [inline] snd_timer_start sound/core/timer.c:690 [inline] snd_timer_user_start.isra.0+0x1e3/0x260 sound/core/timer.c:1985 __snd_timer_user_ioctl.isra.0+0xda8/0x24c0 sound/core/timer.c:2108 snd_timer_user_ioctl+0x77/0xb0 sound/core/timer.c:2129 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae } ... key at: [] __key.0+0x0/0x40 ... acquired at: mark_usage kernel/locking/lockdep.c:4494 [inline] __lock_acquire+0x123a/0x54a0 kernel/locking/lockdep.c:4969 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x36/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1012 [inline] kill_fasync fs/fcntl.c:1033 [inline] kill_fasync+0x132/0x460 fs/fcntl.c:1026 sock_wake_async+0xd2/0x160 net/socket.c:1354 sk_wake_async include/net/sock.h:2327 [inline] sk_wake_async include/net/sock.h:2323 [inline] sock_def_error_report+0x34b/0x4e0 net/core/sock.c:3004 sk_error_report+0x35/0x310 net/core/sock.c:338 __mptcp_error_report+0x25d/0x2f0 net/mptcp/subflow.c:1240 mptcp_release_cb+0x1cc/0x210 net/mptcp/protocol.c:2909 release_sock+0xb4/0x1b0 net/core/sock.c:3185 mptcp_stream_connect+0x243/0x9d0 net/mptcp/protocol.c:3174 __sys_connect_file+0x155/0x1a0 net/socket.c:1879 __sys_connect+0x161/0x190 net/socket.c:1896 __do_sys_connect net/socket.c:1906 [inline] __se_sys_connect net/socket.c:1903 [inline] __x64_sys_connect+0x6f/0xb0 net/socket.c:1903 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae stack backtrace: CPU: 1 PID: 26814 Comm: syz-executor.5 Not tainted 5.14.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 print_irq_inversion_bug kernel/locking/lockdep.c:203 [inline] check_usage_backwards kernel/locking/lockdep.c:4066 [inline] mark_lock_irq kernel/locking/lockdep.c:4156 [inline] mark_lock.cold+0x1d/0x8e kernel/locking/lockdep.c:4593 mark_usage kernel/locking/lockdep.c:4494 [inline] __lock_acquire+0x123a/0x54a0 kernel/locking/lockdep.c:4969 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x36/0x70 kernel/locking/spinlock.c:223 kill_fasync_rcu fs/fcntl.c:1012 [inline] kill_fasync fs/fcntl.c:1033 [inline] kill_fasync+0x132/0x460 fs/fcntl.c:1026 sock_wake_async+0xd2/0x160 net/socket.c:1354 sk_wake_async include/net/sock.h:2327 [inline] sk_wake_async include/net/sock.h:2323 [inline] sock_def_error_report+0x34b/0x4e0 net/core/sock.c:3004 sk_error_report+0x35/0x310 net/core/sock.c:338 __mptcp_error_report+0x25d/0x2f0 net/mptcp/subflow.c:1240 mptcp_release_cb+0x1cc/0x210 net/mptcp/protocol.c:2909 release_sock+0xb4/0x1b0 net/core/sock.c:3185 mptcp_stream_connect+0x243/0x9d0 net/mptcp/protocol.c:3174 __sys_connect_file+0x155/0x1a0 net/socket.c:1879 __sys_connect+0x161/0x190 net/socket.c:1896 __do_sys_connect net/socket.c:1906 [inline] __se_sys_connect net/socket.c:1903 [inline] __x64_sys_connect+0x6f/0xb0 net/socket.c:1903 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1c20d21188 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665e9 RDX: 0000000000000080 RSI: 0000000020003a40 RDI: 0000000000000005 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 0000000000a9fb1f R14: 00007f1c20d21300 R15: 0000000000022000 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: ff c3 inc %ebx 2: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 9: 00 00 00 c: 0f 1f 40 00 nopl 0x0(%rax) 10: 48 89 f8 mov %rdi,%rax 13: 48 89 f7 mov %rsi,%rdi 16: 48 89 d6 mov %rdx,%rsi 19: 48 89 ca mov %rcx,%rdx 1c: 4d 89 c2 mov %r8,%r10 1f: 4d 89 c8 mov %r9,%r8 22: 4c 8b 4c 24 08 mov 0x8(%rsp),%r9 27: 0f 05 syscall 29: 48 3d 01 f0 ff ff cmp $0xfffffffffffff001,%rax <-- trapping instruction 2f: 73 01 jae 0x32 31: c3 retq 32: 48 c7 c1 bc ff ff ff mov $0xffffffffffffffbc,%rcx 39: f7 d8 neg %eax 3b: 64 89 01 mov %eax,%fs:(%rcx) 3e: 48 rex.W