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possible deadlock in free_huge_page

Status: upstream: reported C repro on 2020/12/07 03:16
Reported-by: syzbot+4f0ba0228710c04e580c@syzkaller.appspotmail.com
First crash: 1502d, last: 697d
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 possible deadlock in free_huge_page C error 3 1211d 1493d 0/1 upstream: reported C repro on 2020/12/15 10:55
▶ ▼ Fix bisection attempts (24)
Created Duration User Patch Repo Result
2023/02/19 11:00 2h06m bisect fix linux-4.14.y OK (0) job log log
2023/01/20 03:02 28m bisect fix linux-4.14.y OK (0) job log log
2022/10/27 00:54 34m bisect fix linux-4.14.y OK (0) job log log
2022/09/19 09:18 33m bisect fix linux-4.14.y OK (0) job log log
2022/08/20 08:49 28m bisect fix linux-4.14.y OK (0) job log log
2022/07/21 08:17 31m bisect fix linux-4.14.y OK (0) job log log
2022/06/21 07:06 31m bisect fix linux-4.14.y OK (0) job log log
2022/05/22 06:35 29m bisect fix linux-4.14.y OK (0) job log log
2022/04/22 03:05 27m bisect fix linux-4.14.y OK (0) job log log
2022/03/23 02:27 38m bisect fix linux-4.14.y OK (0) job log log
2022/02/20 11:00 30m bisect fix linux-4.14.y OK (0) job log log
2022/01/21 10:26 33m bisect fix linux-4.14.y OK (0) job log log
2021/12/22 09:46 38m bisect fix linux-4.14.y OK (0) job log log
2021/11/22 08:17 27m bisect fix linux-4.14.y OK (0) job log log
2021/10/23 07:45 31m bisect fix linux-4.14.y OK (0) job log log
2021/09/22 15:20 35m bisect fix linux-4.14.y OK (0) job log log
2021/08/23 13:18 30m bisect fix linux-4.14.y OK (0) job log log
2021/07/24 12:30 29m bisect fix linux-4.14.y OK (0) job log log
2021/06/24 12:00 26m bisect fix linux-4.14.y OK (0) job log log
2021/05/25 05:55 35m bisect fix linux-4.14.y OK (0) job log log
2021/04/25 05:00 39m bisect fix linux-4.14.y OK (0) job log log
2021/03/26 00:23 32m bisect fix linux-4.14.y OK (0) job log log
2021/02/23 23:50 32m bisect fix linux-4.14.y OK (0) job log log
2021/01/23 04:50 33m bisect fix linux-4.14.y OK (0) job log log

Sample crash report:
=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
4.14.212-syzkaller #0 Not tainted
-----------------------------------------------------
syz-executor043/26341 [HC0[0]:SC0[2]:HE1:SE0] is trying to acquire:
 (hugetlb_lock){+.+.}, at: [<ffffffff817df76b>] spin_lock include/linux/spinlock.h:317 [inline]
 (hugetlb_lock){+.+.}, at: [<ffffffff817df76b>] free_huge_page+0x5ab/0x7f0 mm/hugetlb.c:1291

and this task is already holding:
 (slock-AF_INET){+.-.}, at: [<ffffffff862ce7e0>] spin_lock include/linux/spinlock.h:317 [inline]
 (slock-AF_INET){+.-.}, at: [<ffffffff862ce7e0>] tcp_close+0x540/0xed0 net/ipv4/tcp.c:2234
which would create a new lock dependency:
 (slock-AF_INET){+.-.} -> (hugetlb_lock){+.+.}

but this new dependency connects a SOFTIRQ-irq-safe lock:
 (slock-AF_INET){+.-.}

... which became SOFTIRQ-irq-safe at:
  lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
  spin_lock include/linux/spinlock.h:317 [inline]
  sk_clone_lock+0x3cf/0x11e0 net/core/sock.c:1666
  inet_csk_clone_lock+0x1e/0x3f0 net/ipv4/inet_connection_sock.c:815
  tcp_create_openreq_child+0x2c/0x1880 net/ipv4/tcp_minisocks.c:437
  tcp_v4_syn_recv_sock+0xa8/0xf80 net/ipv4/tcp_ipv4.c:1358
  tcp_check_req+0x4c1/0x1460 net/ipv4/tcp_minisocks.c:764
  tcp_v4_rcv+0x1c36/0x3560 net/ipv4/tcp_ipv4.c:1701
  ip_local_deliver_finish+0x3f2/0xab0 net/ipv4/ip_input.c:216
  NF_HOOK include/linux/netfilter.h:250 [inline]
  ip_local_deliver+0x167/0x460 net/ipv4/ip_input.c:257
  dst_input include/net/dst.h:476 [inline]
  ip_rcv_finish+0x6e3/0x19f0 net/ipv4/ip_input.c:396
  NF_HOOK include/linux/netfilter.h:250 [inline]
  ip_rcv+0x8a7/0xf01 net/ipv4/ip_input.c:493
  __netif_receive_skb_core+0x15ee/0x2a30 net/core/dev.c:4474
  __netif_receive_skb+0x27/0x1a0 net/core/dev.c:4512
  netif_receive_skb_internal+0xd7/0x580 net/core/dev.c:4585
  napi_skb_finish net/core/dev.c:4946 [inline]
  napi_gro_receive+0x2e2/0x400 net/core/dev.c:4977
  receive_buf+0x5ef/0x4810 drivers/net/virtio_net.c:852
  virtnet_receive drivers/net/virtio_net.c:1098 [inline]
  virtnet_poll+0x4b7/0x960 drivers/net/virtio_net.c:1189
  napi_poll net/core/dev.c:5596 [inline]
  net_rx_action+0x466/0xfd0 net/core/dev.c:5662
  __do_softirq+0x254/0xa1d kernel/softirq.c:288
  run_ksoftirqd+0x50/0x1a0 kernel/softirq.c:670
  smpboot_thread_fn+0x5c1/0x920 kernel/smpboot.c:164
  kthread+0x30d/0x420 kernel/kthread.c:232
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

to a SOFTIRQ-irq-unsafe lock:
 (hugetlb_lock){+.+.}

... which became SOFTIRQ-irq-unsafe at:
...
  lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
  spin_lock include/linux/spinlock.h:317 [inline]
  hugetlb_overcommit_handler+0x283/0x400 mm/hugetlb.c:2992
  proc_sys_call_handler.isra.0+0x1ba/0x340 fs/proc/proc_sysctl.c:598
  __vfs_write+0xe4/0x630 fs/read_write.c:480
  vfs_write+0x17f/0x4d0 fs/read_write.c:544
  SYSC_write fs/read_write.c:590 [inline]
  SyS_write+0xf2/0x210 fs/read_write.c:582
  do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
  entry_SYSCALL_64_after_hwframe+0x46/0xbb

other info that might help us debug this:

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(hugetlb_lock);
                               local_irq_disable();
                               lock(slock-AF_INET);
                               lock(hugetlb_lock);
  <Interrupt>
    lock(slock-AF_INET);

 *** DEADLOCK ***

3 locks held by syz-executor043/26341:
 #0:  (&sb->s_type->i_mutex_key#13){+.+.}, at: [<ffffffff85d722c6>] inode_lock include/linux/fs.h:719 [inline]
 #0:  (&sb->s_type->i_mutex_key#13){+.+.}, at: [<ffffffff85d722c6>] __sock_release+0x86/0x2b0 net/socket.c:601
 #1:  (sk_lock-AF_INET){+.+.}, at: [<ffffffff862ce2c5>] lock_sock include/net/sock.h:1471 [inline]
 #1:  (sk_lock-AF_INET){+.+.}, at: [<ffffffff862ce2c5>] tcp_close+0x25/0xed0 net/ipv4/tcp.c:2144
 #2:  (slock-AF_INET){+.-.}, at: [<ffffffff862ce7e0>] spin_lock include/linux/spinlock.h:317 [inline]
 #2:  (slock-AF_INET){+.-.}, at: [<ffffffff862ce7e0>] tcp_close+0x540/0xed0 net/ipv4/tcp.c:2234

the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (slock-AF_INET){+.-.} ops: 384849 {
   HARDIRQ-ON-W at:
                    lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
                    __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
                    _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:176
                    spin_lock_bh include/linux/spinlock.h:322 [inline]
                    lock_sock_nested+0x39/0x100 net/core/sock.c:2788
                    lock_sock include/net/sock.h:1471 [inline]
                    inet_autobind+0x1a/0x180 net/ipv4/af_inet.c:178
                    inet_dgram_connect+0x134/0x1f0 net/ipv4/af_inet.c:538
                    SYSC_connect net/socket.c:1655 [inline]
                    SyS_connect+0x1f4/0x240 net/socket.c:1636
                    do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
                    entry_SYSCALL_64_after_hwframe+0x46/0xbb
   IN-SOFTIRQ-W at:
                    lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
                    __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
                    _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
                    spin_lock include/linux/spinlock.h:317 [inline]
                    sk_clone_lock+0x3cf/0x11e0 net/core/sock.c:1666
                    inet_csk_clone_lock+0x1e/0x3f0 net/ipv4/inet_connection_sock.c:815
                    tcp_create_openreq_child+0x2c/0x1880 net/ipv4/tcp_minisocks.c:437
                    tcp_v4_syn_recv_sock+0xa8/0xf80 net/ipv4/tcp_ipv4.c:1358
                    tcp_check_req+0x4c1/0x1460 net/ipv4/tcp_minisocks.c:764
                    tcp_v4_rcv+0x1c36/0x3560 net/ipv4/tcp_ipv4.c:1701
                    ip_local_deliver_finish+0x3f2/0xab0 net/ipv4/ip_input.c:216
                    NF_HOOK include/linux/netfilter.h:250 [inline]
                    ip_local_deliver+0x167/0x460 net/ipv4/ip_input.c:257
                    dst_input include/net/dst.h:476 [inline]
                    ip_rcv_finish+0x6e3/0x19f0 net/ipv4/ip_input.c:396
                    NF_HOOK include/linux/netfilter.h:250 [inline]
                    ip_rcv+0x8a7/0xf01 net/ipv4/ip_input.c:493
                    __netif_receive_skb_core+0x15ee/0x2a30 net/core/dev.c:4474
                    __netif_receive_skb+0x27/0x1a0 net/core/dev.c:4512
                    netif_receive_skb_internal+0xd7/0x580 net/core/dev.c:4585
                    napi_skb_finish net/core/dev.c:4946 [inline]
                    napi_gro_receive+0x2e2/0x400 net/core/dev.c:4977
                    receive_buf+0x5ef/0x4810 drivers/net/virtio_net.c:852
                    virtnet_receive drivers/net/virtio_net.c:1098 [inline]
                    virtnet_poll+0x4b7/0x960 drivers/net/virtio_net.c:1189
                    napi_poll net/core/dev.c:5596 [inline]
                    net_rx_action+0x466/0xfd0 net/core/dev.c:5662
                    __do_softirq+0x254/0xa1d kernel/softirq.c:288
                    run_ksoftirqd+0x50/0x1a0 kernel/softirq.c:670
                    smpboot_thread_fn+0x5c1/0x920 kernel/smpboot.c:164
                    kthread+0x30d/0x420 kernel/kthread.c:232
                    ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
   INITIAL USE at:
                   lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
                   __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
                   _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:176
                   spin_lock_bh include/linux/spinlock.h:322 [inline]
                   lock_sock_nested+0x39/0x100 net/core/sock.c:2788
                   lock_sock include/net/sock.h:1471 [inline]
                   inet_autobind+0x1a/0x180 net/ipv4/af_inet.c:178
                   inet_dgram_connect+0x134/0x1f0 net/ipv4/af_inet.c:538
                   SYSC_connect net/socket.c:1655 [inline]
                   SyS_connect+0x1f4/0x240 net/socket.c:1636
                   do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
                   entry_SYSCALL_64_after_hwframe+0x46/0xbb
 }
 ... key      at: [<ffffffff8c981a70>] af_family_slock_keys+0x10/0x180
 ... acquired at:
   lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
   __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
   _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
   spin_lock include/linux/spinlock.h:317 [inline]
   free_huge_page+0x5ab/0x7f0 mm/hugetlb.c:1291
   __put_page+0xb9/0x2f0 mm/swap.c:111
   put_page include/linux/mm.h:875 [inline]
   __skb_frag_unref include/linux/skbuff.h:2813 [inline]
   skb_release_data+0x25a/0x820 net/core/skbuff.c:568
   skb_release_all net/core/skbuff.c:631 [inline]
   __kfree_skb+0x46/0x60 net/core/skbuff.c:645
   sk_wmem_free_skb include/net/sock.h:1425 [inline]
   tcp_write_queue_purge include/net/tcp.h:1631 [inline]
   tcp_v4_destroy_sock+0x223/0x920 net/ipv4/tcp_ipv4.c:1904
   inet_csk_destroy_sock+0x169/0x400 net/ipv4/inet_connection_sock.c:866
   tcp_close+0x85e/0xed0 net/ipv4/tcp.c:2298
   inet_release+0xdf/0x1b0 net/ipv4/af_inet.c:425
   __sock_release+0xcd/0x2b0 net/socket.c:602
   sock_close+0x15/0x20 net/socket.c:1139
   __fput+0x25f/0x7a0 fs/file_table.c:210
   task_work_run+0x11f/0x190 kernel/task_work.c:113
   exit_task_work include/linux/task_work.h:22 [inline]
   do_exit+0xa44/0x2850 kernel/exit.c:868
   do_group_exit+0x100/0x2e0 kernel/exit.c:965
   get_signal+0x38d/0x1ca0 kernel/signal.c:2423
   do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:814
   exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
   prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
   syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
   do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
   entry_SYSCALL_64_after_hwframe+0x46/0xbb


the dependencies between the lock to be acquired
 and SOFTIRQ-irq-unsafe lock:
-> (hugetlb_lock){+.+.} ops: 305245 {
   HARDIRQ-ON-W at:
                    lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
                    __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
                    _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
                    spin_lock include/linux/spinlock.h:317 [inline]
                    hugetlb_overcommit_handler+0x283/0x400 mm/hugetlb.c:2992
                    proc_sys_call_handler.isra.0+0x1ba/0x340 fs/proc/proc_sysctl.c:598
                    __vfs_write+0xe4/0x630 fs/read_write.c:480
                    vfs_write+0x17f/0x4d0 fs/read_write.c:544
                    SYSC_write fs/read_write.c:590 [inline]
                    SyS_write+0xf2/0x210 fs/read_write.c:582
                    do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
                    entry_SYSCALL_64_after_hwframe+0x46/0xbb
   SOFTIRQ-ON-W at:
                    lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
                    __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
                    _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
                    spin_lock include/linux/spinlock.h:317 [inline]
                    hugetlb_overcommit_handler+0x283/0x400 mm/hugetlb.c:2992
                    proc_sys_call_handler.isra.0+0x1ba/0x340 fs/proc/proc_sysctl.c:598
                    __vfs_write+0xe4/0x630 fs/read_write.c:480
                    vfs_write+0x17f/0x4d0 fs/read_write.c:544
                    SYSC_write fs/read_write.c:590 [inline]
                    SyS_write+0xf2/0x210 fs/read_write.c:582
                    do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
                    entry_SYSCALL_64_after_hwframe+0x46/0xbb
   INITIAL USE at:
                   lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
                   __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
                   _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
                   spin_lock include/linux/spinlock.h:317 [inline]
                   hugetlb_overcommit_handler+0x283/0x400 mm/hugetlb.c:2992
                   proc_sys_call_handler.isra.0+0x1ba/0x340 fs/proc/proc_sysctl.c:598
                   __vfs_write+0xe4/0x630 fs/read_write.c:480
                   vfs_write+0x17f/0x4d0 fs/read_write.c:544
                   SYSC_write fs/read_write.c:590 [inline]
                   SyS_write+0xf2/0x210 fs/read_write.c:582
                   do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
                   entry_SYSCALL_64_after_hwframe+0x46/0xbb
 }
 ... key      at: [<ffffffff89000698>] hugetlb_lock+0x18/0x15e0
 ... acquired at:
   lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
   __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
   _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
   spin_lock include/linux/spinlock.h:317 [inline]
   free_huge_page+0x5ab/0x7f0 mm/hugetlb.c:1291
   __put_page+0xb9/0x2f0 mm/swap.c:111
   put_page include/linux/mm.h:875 [inline]
   __skb_frag_unref include/linux/skbuff.h:2813 [inline]
   skb_release_data+0x25a/0x820 net/core/skbuff.c:568
   skb_release_all net/core/skbuff.c:631 [inline]
   __kfree_skb+0x46/0x60 net/core/skbuff.c:645
   sk_wmem_free_skb include/net/sock.h:1425 [inline]
   tcp_write_queue_purge include/net/tcp.h:1631 [inline]
   tcp_v4_destroy_sock+0x223/0x920 net/ipv4/tcp_ipv4.c:1904
   inet_csk_destroy_sock+0x169/0x400 net/ipv4/inet_connection_sock.c:866
   tcp_close+0x85e/0xed0 net/ipv4/tcp.c:2298
   inet_release+0xdf/0x1b0 net/ipv4/af_inet.c:425
   __sock_release+0xcd/0x2b0 net/socket.c:602
   sock_close+0x15/0x20 net/socket.c:1139
   __fput+0x25f/0x7a0 fs/file_table.c:210
   task_work_run+0x11f/0x190 kernel/task_work.c:113
   exit_task_work include/linux/task_work.h:22 [inline]
   do_exit+0xa44/0x2850 kernel/exit.c:868
   do_group_exit+0x100/0x2e0 kernel/exit.c:965
   get_signal+0x38d/0x1ca0 kernel/signal.c:2423
   do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:814
   exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
   prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
   syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
   do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
   entry_SYSCALL_64_after_hwframe+0x46/0xbb


stack backtrace:
CPU: 1 PID: 26341 Comm: syz-executor043 Not tainted 4.14.212-syzkaller #0
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+0x1b2/0x283 lib/dump_stack.c:58
 print_bad_irq_dependency kernel/locking/lockdep.c:1609 [inline]
 check_usage.cold+0x806/0xbe6 kernel/locking/lockdep.c:1641
 check_irq_usage kernel/locking/lockdep.c:1697 [inline]
 check_prev_add_irq kernel/locking/lockdep_states.h:8 [inline]
 check_prev_add kernel/locking/lockdep.c:1910 [inline]
 check_prevs_add kernel/locking/lockdep.c:2022 [inline]
 validate_chain kernel/locking/lockdep.c:2464 [inline]
 __lock_acquire+0x1cfc/0x3f20 kernel/locking/lockdep.c:3491
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
 spin_lock include/linux/spinlock.h:317 [inline]
 free_huge_page+0x5ab/0x7f0 mm/hugetlb.c:1291
 __put_page+0xb9/0x2f0 mm/swap.c:111
 put_page include/linux/mm.h:875 [inline]
 __skb_frag_unref include/linux/skbuff.h:2813 [inline]
 skb_release_data+0x25a/0x820 net/core/skbuff.c:568
 skb_release_all net/core/skbuff.c:631 [inline]
 __kfree_skb+0x46/0x60 net/core/skbuff.c:645
 sk_wmem_free_skb include/net/sock.h:1425 [inline]
 tcp_write_queue_purge include/net/tcp.h:1631 [inline]
 tcp_v4_destroy_sock+0x223/0x920 net/ipv4/tcp_ipv4.c:1904
 inet_csk_destroy_sock+0x169/0x400 net/ipv4/inet_connection_sock.c:866
 tcp_close+0x85e/0xed0 net/ipv4/tcp.c:2298
 inet_release+0xdf/0x1b0 net/ipv4/af_inet.c:425
 __sock_release+0xcd/0x2b0 net/socket.c:602
 sock_close+0x15/0x20 net/socket.c:1139
 __fput+0x25f/0x7a0 fs/file_table.c:210
 task_work_run+0x11f/0x190 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xa44/0x2850 kernel/exit.c:868
 do_group_exit+0x100/0x2e0 kernel/exit.c:965
 get_signal+0x38d/0x1ca0 kernel/signal.c:2423
 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x446c79
RSP: 002b:00007fbc85d0fdb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00000000006dbc48 RCX: 0000000000446c79
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc48
RBP: 00000000006dbc40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c
R13: 00007ffc4413cd9f R14: 00007fbc85d109c0 R15: 20c49ba5e353f7cf

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/12/24 04:50 linux-4.14.y 3f2ecb86cb90 c2c1d1dd .config console log report syz C ci2-linux-4-14
2020/12/20 10:13 linux-4.14.y 3f2ecb86cb90 04201c06 .config console log report syz C ci2-linux-4-14
2020/12/07 03:34 linux-4.14.y c196b3a9c83a c521566d .config console log report syz C ci2-linux-4-14
2020/12/07 03:15 linux-4.14.y c196b3a9c83a c521566d .config console log report info ci2-linux-4-14
* Struck through repros no longer work on HEAD.