====================================================== WARNING: possible circular locking dependency detected 6.10.0-syzkaller-11185-g2c9b3512402e #0 Not tainted ------------------------------------------------------ syz.3.3287/17952 is trying to acquire lock: ffff888056def058 (sk_lock-AF_SMC){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline] ffff888056def058 (sk_lock-AF_SMC){+.+.}-{0:0}, at: smc_shutdown+0x65/0x800 net/smc/af_smc.c:2921 but task is already holding lock: ffff888057051870 (&nsock->tx_lock){+.+.}-{3:3}, at: sock_shutdown+0x16f/0x280 drivers/block/nbd.c:403 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&nsock->tx_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 sock_shutdown+0x16f/0x280 drivers/block/nbd.c:403 nbd_clear_sock drivers/block/nbd.c:1333 [inline] nbd_config_put+0x1e6/0x750 drivers/block/nbd.c:1357 nbd_release+0xb7/0x190 drivers/block/nbd.c:1652 blkdev_put_whole+0xad/0xf0 block/bdev.c:673 bdev_release+0x496/0x6f0 block/bdev.c:1096 blkdev_release+0x15/0x20 block/fops.c:638 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:222 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #5 (&nbd->config_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 refcount_dec_and_mutex_lock+0x51/0xe0 lib/refcount.c:118 nbd_config_put+0x31/0x750 drivers/block/nbd.c:1340 nbd_release+0xb7/0x190 drivers/block/nbd.c:1652 blkdev_put_whole+0xad/0xf0 block/bdev.c:673 bdev_release+0x496/0x6f0 block/bdev.c:1096 blkdev_release+0x15/0x20 block/fops.c:638 __fput+0x408/0xbb0 fs/file_table.c:422 __fput_sync+0x47/0x50 fs/file_table.c:507 __do_sys_close fs/open.c:1566 [inline] __se_sys_close fs/open.c:1551 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1551 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 bdev_open+0x41a/0xe40 block/bdev.c:897 bdev_file_open_by_dev block/bdev.c:1011 [inline] bdev_file_open_by_dev+0x17d/0x210 block/bdev.c:986 disk_scan_partitions+0x1ed/0x320 block/genhd.c:367 device_add_disk+0xfbb/0x12d0 block/genhd.c:510 pmem_attach_disk+0x9ab/0x13c0 drivers/nvdimm/pmem.c:576 nd_pmem_probe+0x1a9/0x1f0 drivers/nvdimm/pmem.c:649 nvdimm_bus_probe+0x169/0x5d0 drivers/nvdimm/bus.c:91 call_driver_probe drivers/base/dd.c:578 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:656 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:798 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:828 __driver_attach+0x283/0x580 drivers/base/dd.c:1214 bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:368 bus_add_driver+0x2e9/0x690 drivers/base/bus.c:673 driver_register+0x15c/0x4b0 drivers/base/driver.c:246 __nd_driver_register+0x103/0x1a0 drivers/nvdimm/bus.c:619 do_one_initcall+0x128/0x630 init/main.c:1267 do_initcall_level init/main.c:1329 [inline] do_initcalls init/main.c:1345 [inline] do_basic_setup init/main.c:1364 [inline] kernel_init_freeable+0x660/0xc50 init/main.c:1578 kernel_init+0x1c/0x2b0 init/main.c:1467 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #3 (&nvdimm_namespace_key){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 device_lock include/linux/device.h:1009 [inline] uevent_show+0x188/0x3b0 drivers/base/core.c:2743 dev_attr_show+0x53/0xe0 drivers/base/core.c:2437 sysfs_kf_seq_show+0x223/0x3e0 fs/sysfs/file.c:59 seq_read_iter+0x4fa/0x12c0 fs/seq_file.c:230 kernfs_fop_read_iter+0x41a/0x590 fs/kernfs/file.c:279 new_sync_read fs/read_write.c:395 [inline] vfs_read+0x869/0xbd0 fs/read_write.c:476 ksys_read+0x12f/0x260 fs/read_write.c:619 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (kn->active#5){++++}-{0:0}: kernfs_drain+0x48f/0x590 fs/kernfs/dir.c:500 __kernfs_remove+0x281/0x670 fs/kernfs/dir.c:1486 kernfs_remove_by_name_ns+0xb2/0x130 fs/kernfs/dir.c:1694 sysfs_remove_file include/linux/sysfs.h:773 [inline] device_remove_file drivers/base/core.c:3061 [inline] device_remove_file drivers/base/core.c:3057 [inline] device_del+0x381/0x9f0 drivers/base/core.c:3866 unregister_netdevice_many_notify+0x103b/0x1e40 net/core/dev.c:11377 unregister_netdevice_many net/core/dev.c:11405 [inline] unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11280 unregister_netdevice include/linux/netdevice.h:3129 [inline] unregister_netdev+0x1c/0x30 net/core/dev.c:11423 slip_close+0x165/0x1c0 drivers/net/slip/slip.c:906 tty_ldisc_close+0x111/0x1a0 drivers/tty/tty_ldisc.c:455 tty_ldisc_kill+0x8e/0x150 drivers/tty/tty_ldisc.c:613 tty_ldisc_release+0x17b/0x2a0 drivers/tty/tty_ldisc.c:781 tty_release_struct+0x23/0xe0 drivers/tty/tty_io.c:1696 tty_release+0xe33/0x1420 drivers/tty/tty_io.c:1867 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:222 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #1 (rtnl_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 smc_vlan_by_tcpsk+0x251/0x620 net/smc/smc_core.c:1853 __smc_connect+0x466/0x48f0 net/smc/af_smc.c:1522 smc_connect+0x2fc/0x760 net/smc/af_smc.c:1702 __sys_connect_file+0x15f/0x1a0 net/socket.c:2061 __sys_connect+0x149/0x170 net/socket.c:2078 __do_sys_connect net/socket.c:2088 [inline] __se_sys_connect net/socket.c:2085 [inline] __ia32_sys_connect+0x71/0xb0 net/socket.c:2085 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #0 (sk_lock-AF_SMC){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142 lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3543 lock_sock include/net/sock.h:1607 [inline] smc_shutdown+0x65/0x800 net/smc/af_smc.c:2921 nbd_mark_nsock_dead+0xae/0x5d0 drivers/block/nbd.c:303 sock_shutdown+0x17c/0x280 drivers/block/nbd.c:404 nbd_clear_sock drivers/block/nbd.c:1333 [inline] nbd_config_put+0x1e6/0x750 drivers/block/nbd.c:1357 nbd_release+0xb7/0x190 drivers/block/nbd.c:1652 blkdev_put_whole+0xad/0xf0 block/bdev.c:673 bdev_release+0x496/0x6f0 block/bdev.c:1096 blkdev_release+0x15/0x20 block/fops.c:638 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:222 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e other info that might help us debug this: Chain exists of: sk_lock-AF_SMC --> &nbd->config_lock --> &nsock->tx_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&nsock->tx_lock); lock(&nbd->config_lock); lock(&nsock->tx_lock); lock(sk_lock-AF_SMC); *** DEADLOCK *** 3 locks held by syz.3.3287/17952: #0: ffff88801f2fe4c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_release+0x166/0x6f0 block/bdev.c:1080 #1: ffff88801f2f7998 (&nbd->config_lock){+.+.}-{3:3}, at: refcount_dec_and_mutex_lock+0x51/0xe0 lib/refcount.c:118 #2: ffff888057051870 (&nsock->tx_lock){+.+.}-{3:3}, at: sock_shutdown+0x16f/0x280 drivers/block/nbd.c:403 stack backtrace: CPU: 0 PID: 17952 Comm: syz.3.3287 Not tainted 6.10.0-syzkaller-11185-g2c9b3512402e #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2186 check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142 lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3543 lock_sock include/net/sock.h:1607 [inline] smc_shutdown+0x65/0x800 net/smc/af_smc.c:2921 nbd_mark_nsock_dead+0xae/0x5d0 drivers/block/nbd.c:303 sock_shutdown+0x17c/0x280 drivers/block/nbd.c:404 nbd_clear_sock drivers/block/nbd.c:1333 [inline] nbd_config_put+0x1e6/0x750 drivers/block/nbd.c:1357 nbd_release+0xb7/0x190 drivers/block/nbd.c:1652 blkdev_put_whole+0xad/0xf0 block/bdev.c:673 bdev_release+0x496/0x6f0 block/bdev.c:1096 blkdev_release+0x15/0x20 block/fops.c:638 __fput+0x408/0xbb0 fs/file_table.c:422 task_work_run+0x14e/0x250 kernel/task_work.c:222 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fb8579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000ffe31cac EFLAGS: 00000202 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 000000000000001e RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000000004e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 block nbd3: shutting down sockets ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi