netlink: 28 bytes leftover after parsing attributes in process `syz-executor.0'. ====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/17679 is trying to acquire lock: 00000000e18db912 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: flush_workqueue+0xe8/0x13e0 kernel/workqueue.c:2658 but task is already holding lock: 00000000f0add123 (&nbd->config_lock){+.+.}, at: refcount_dec_and_mutex_lock lib/refcount.c:311 [inline] 00000000f0add123 (&nbd->config_lock){+.+.}, at: refcount_dec_and_mutex_lock+0x4a/0x80 lib/refcount.c:306 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #8 (&nbd->config_lock){+.+.}: nbd_open+0x2e2/0x6f0 drivers/block/nbd.c:1428 __blkdev_get+0x372/0x1480 fs/block_dev.c:1494 blkdev_get+0xb0/0x940 fs/block_dev.c:1627 blkdev_open+0x202/0x290 fs/block_dev.c:1788 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #7 (nbd_index_mutex){+.+.}: nbd_open+0x73/0x6f0 drivers/block/nbd.c:1415 __blkdev_get+0x372/0x1480 fs/block_dev.c:1494 blkdev_get+0xb0/0x940 fs/block_dev.c:1627 blkdev_open+0x202/0x290 fs/block_dev.c:1788 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #6 (&bdev->bd_mutex){+.+.}: blkdev_put+0x30/0x520 fs/block_dev.c:1839 btrfs_close_bdev fs/btrfs/volumes.c:1033 [inline] btrfs_close_one_device fs/btrfs/volumes.c:1057 [inline] close_fs_devices.part.0+0x24d/0x8e0 fs/btrfs/volumes.c:1085 close_fs_devices fs/btrfs/volumes.c:1117 [inline] btrfs_close_devices+0x95/0x1f0 fs/btrfs/volumes.c:1103 close_ctree+0x3c8/0x850 fs/btrfs/disk-io.c:4047 generic_shutdown_super+0x144/0x370 fs/super.c:456 kill_anon_super+0x36/0x60 fs/super.c:1032 btrfs_kill_super+0x49/0x550 fs/btrfs/super.c:2221 deactivate_locked_super+0x94/0x160 fs/super.c:329 deactivate_super+0x174/0x1a0 fs/super.c:360 cleanup_mnt+0x1a8/0x290 fs/namespace.c:1098 task_work_run+0x148/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #5 (&fs_devs->device_list_mutex){+.+.}: btrfs_finish_chunk_alloc+0x27b/0xf90 fs/btrfs/volumes.c:4938 btrfs_create_pending_block_groups+0x242/0x590 fs/btrfs/extent-tree.c:10134 __btrfs_end_transaction+0x21a/0xb00 fs/btrfs/transaction.c:855 flush_space+0xa41/0xee0 fs/btrfs/extent-tree.c:4861 btrfs_async_reclaim_metadata_space+0x466/0x1050 fs/btrfs/extent-tree.c:4977 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #4 (sb_internal#4){.+.+}: sb_start_intwrite include/linux/fs.h:1626 [inline] start_transaction+0xa37/0xf90 fs/btrfs/transaction.c:528 btrfs_dirty_inode+0xe3/0x210 fs/btrfs/inode.c:6165 btrfs_update_time+0x33b/0x3d0 fs/btrfs/inode.c:6207 update_time fs/inode.c:1675 [inline] touch_atime+0x23c/0x2a0 fs/inode.c:1746 file_accessed include/linux/fs.h:2123 [inline] btrfs_file_mmap+0x11b/0x160 fs/btrfs/file.c:2274 call_mmap include/linux/fs.h:1826 [inline] mmap_region+0xc94/0x16b0 mm/mmap.c:1757 do_mmap+0x8e8/0x1080 mm/mmap.c:1530 do_mmap_pgoff include/linux/mm.h:2329 [inline] vm_mmap_pgoff+0x197/0x200 mm/util.c:357 ksys_mmap_pgoff+0x298/0x5a0 mm/mmap.c:1580 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #3 (&mm->mmap_sem){++++}: _copy_to_iter+0x3d0/0xea0 lib/iov_iter.c:564 copy_to_iter include/linux/uio.h:106 [inline] skb_copy_datagram_iter+0x469/0x9e0 net/core/datagram.c:431 skb_copy_datagram_msg include/linux/skbuff.h:3347 [inline] unix_dgram_recvmsg+0x3b7/0xdb0 net/unix/af_unix.c:2180 sock_recvmsg_nosec net/socket.c:859 [inline] sock_recvmsg net/socket.c:866 [inline] sock_recvmsg net/socket.c:862 [inline] __sys_recvfrom+0x249/0x3a0 net/socket.c:1956 __do_sys_recvfrom net/socket.c:1974 [inline] __se_sys_recvfrom net/socket.c:1970 [inline] __x64_sys_recvfrom+0xdd/0x1b0 net/socket.c:1970 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&u->iolock){+.+.}: unix_stream_read_generic+0x2de/0x1a40 net/unix/af_unix.c:2322 unix_stream_recvmsg+0xb1/0xf0 net/unix/af_unix.c:2505 sock_recvmsg_nosec net/socket.c:859 [inline] sock_recvmsg net/socket.c:866 [inline] sock_recvmsg+0xca/0x110 net/socket.c:862 sock_xmit+0x37d/0x5c0 drivers/block/nbd.c:439 nbd_read_stat drivers/block/nbd.c:633 [inline] recv_work+0x1e9/0x1100 drivers/block/nbd.c:732 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #1 ((work_completion)(&args->work)){+.+.}: worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #0 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}: flush_workqueue+0x117/0x13e0 kernel/workqueue.c:2661 drain_workqueue+0x1a5/0x460 kernel/workqueue.c:2826 destroy_workqueue+0x75/0x790 kernel/workqueue.c:4183 nbd_config_put+0x3c5/0x870 drivers/block/nbd.c:1175 nbd_release+0xf4/0x170 drivers/block/nbd.c:1461 __blkdev_put+0x636/0x870 fs/block_dev.c:1819 blkdev_close+0x86/0xb0 fs/block_dev.c:1888 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbf3/0x2be0 kernel/exit.c:870 __do_sys_exit kernel/exit.c:936 [inline] __se_sys_exit kernel/exit.c:934 [inline] __x64_sys_exit+0x3e/0x50 kernel/exit.c:934 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: (wq_completion)"knbd%d-recv"nbd->index --> nbd_index_mutex --> &nbd->config_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&nbd->config_lock); lock(nbd_index_mutex); lock(&nbd->config_lock); lock((wq_completion)"knbd%d-recv"nbd->index); *** DEADLOCK *** 2 locks held by syz-executor.4/17679: #0: 000000000e41f58b (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0xfc/0x870 fs/block_dev.c:1806 #1: 00000000f0add123 (&nbd->config_lock){+.+.}, at: refcount_dec_and_mutex_lock lib/refcount.c:311 [inline] #1: 00000000f0add123 (&nbd->config_lock){+.+.}, at: refcount_dec_and_mutex_lock+0x4a/0x80 lib/refcount.c:306 stack backtrace: CPU: 1 PID: 17679 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 flush_workqueue+0x117/0x13e0 kernel/workqueue.c:2661 drain_workqueue+0x1a5/0x460 kernel/workqueue.c:2826 destroy_workqueue+0x75/0x790 kernel/workqueue.c:4183 nbd_config_put+0x3c5/0x870 drivers/block/nbd.c:1175 nbd_release+0xf4/0x170 drivers/block/nbd.c:1461 __blkdev_put+0x636/0x870 fs/block_dev.c:1819 blkdev_close+0x86/0xb0 fs/block_dev.c:1888 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbf3/0x2be0 kernel/exit.c:870 __do_sys_exit kernel/exit.c:936 [inline] __se_sys_exit kernel/exit.c:934 [inline] __x64_sys_exit+0x3e/0x50 kernel/exit.c:934 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f61841ee0c9 Code: Bad RIP value. RSP: 002b:00007f6182760118 EFLAGS: 00000246 ORIG_RAX: 000000000000003c RAX: ffffffffffffffda RBX: 00007f618430df80 RCX: 00007f61841ee0c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f6184249ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff1f630caf R14: 00007f6182760300 R15: 0000000000022000 block nbd4: Could not allocate knbd recv work queue. block nbd4: shutting down sockets xt_TCPMSS: path-MTU clamping only supported in FORWARD, OUTPUT and POSTROUTING hooks netlink: 76 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 28 bytes leftover after parsing attributes in process `syz-executor.0'. REISERFS (device loop4): found reiserfs format "3.5" with non-standard journal kauditd_printk_skb: 46 callbacks suppressed audit: type=1804 audit(1675019641.447:401): pid=17772 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir713841428/syzkaller.NNutWr/85/file0/bus" dev="loop3" ino=169 res=1 REISERFS (device loop4): using ordered data mode audit: type=1804 audit(1675019641.477:402): pid=17772 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir713841428/syzkaller.NNutWr/85/file0/bus" dev="loop3" ino=169 res=1 reiserfs: using flush barriers attempt to access beyond end of device loop3: rw=1, want=2064, limit=2048 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 REISERFS (device loop4): journal params: device loop4, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30 REISERFS (device loop4): checking transaction log (loop4) REISERFS (device loop4): Using r5 hash to sort names REISERFS warning (device loop4): super-6502 reiserfs_getopt: unknown mount option "ÿî§<< G4š¶mRŸ±â½ÆuÆÌëê0º‰wÆ2ÝËàíù†¶Žæ" audit: type=1804 audit(1675019644.077:403): pid=17797 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.0" name="/root/syzkaller-testdir2831163601/syzkaller.SYs067/109/bus" dev="sda1" ino=14867 res=1 REISERFS (device loop4): found reiserfs format "3.5" with non-standard journal audit: type=1804 audit(1675019644.157:404): pid=17829 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.0" name="/root/syzkaller-testdir2831163601/syzkaller.SYs067/109/bus" dev="sda1" ino=14867 res=1 REISERFS (device loop4): using ordered data mode reiserfs: using flush barriers audit: type=1804 audit(1675019644.187:405): pid=17820 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir713841428/syzkaller.NNutWr/87/file0/bus" dev="loop3" ino=170 res=1 REISERFS (device loop4): journal params: device loop4, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30 REISERFS (device loop4): checking transaction log (loop4) audit: type=1804 audit(1675019644.197:406): pid=17820 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir713841428/syzkaller.NNutWr/87/file0/bus" dev="loop3" ino=170 res=1 IPVS: ftp: loaded support on port[0] = 21 REISERFS (device loop4): Using r5 hash to sort names REISERFS warning (device loop4): super-6502 reiserfs_getopt: unknown mount option "ÿî§<< G4š¶mRŸ±â½ÆuÆÌëê0º‰wÆ2ÝËàíù†¶Žæ" audit: type=1804 audit(1675019644.397:407): pid=17853 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir713841428/syzkaller.NNutWr/88/bus" dev="sda1" ino=14883 res=1 audit: type=1804 audit(1675019644.467:408): pid=17860 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.3" name="/root/syzkaller-testdir713841428/syzkaller.NNutWr/88/bus" dev="sda1" ino=14883 res=1 9pnet_virtio: no channels available for device 127.0.0.1 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 REISERFS warning (device loop4): super-6502 reiserfs_getopt: unknown mount option "ÿî§<< G4š¶mRŸ±â½ÆuÆÌëê0º‰wÆ2ÝËàíù†¶Žæ" audit: type=1804 audit(1675019644.977:409): pid=17892 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.0" name="/root/syzkaller-testdir2831163601/syzkaller.SYs067/110/bus" dev="sda1" ino=14867 res=1 audit: type=1804 audit(1675019645.007:410): pid=17893 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.0" name="/root/syzkaller-testdir2831163601/syzkaller.SYs067/110/bus" dev="sda1" ino=14867 res=1 9pnet_virtio: no channels available for device 127.0.0.1 IPVS: ftp: loaded support on port[0] = 21 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 9pnet_virtio: no channels available for device 127.0.0.1 IPVS: ftp: loaded support on port[0] = 21 XFS (loop4): Mounting V4 Filesystem XFS (loop4): Ending clean mount XFS (loop4): Quotacheck needed: Please wait. XFS (loop4): Quotacheck: Done. overlayfs: unrecognized mount option "upperdir<./bws" or missing value UDF-fs: warning (device loop2): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 512 failed UDF-fs: warning (device loop2): udf_load_vrs: No VRS found XFS (loop4): Unmounting Filesystem UDF-fs: Scanning with blocksize 1024 failed UDF-fs: warning (device loop2): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 2048 failed UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) kauditd_printk_skb: 4 callbacks suppressed audit: type=1800 audit(1675019647.717:415): pid=18114 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="loop2" ino=842 res=0 UDF-fs: warning (device loop2): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 512 failed UDF-fs: warning (device loop2): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 1024 failed UDF-fs: warning (device loop2): udf_load_vrs: No VRS found UDF-fs: Scanning with blocksize 2048 failed UDF-fs: INFO Mounting volume 'LinuxUDF', timestamp 2022/11/22 14:59 (1000) audit: type=1800 audit(1675019648.457:416): pid=18193 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="loop2" ino=842 res=0