Hello, syzbot found the following issue on: HEAD commit: c4b9570cfb63 Merge tag 'audit-pr-20250121' of git://git.ke.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=122d4ab0580000 kernel config: https://syzkaller.appspot.com/x/.config?x=c857c6065c39b1e2 dashboard link: https://syzkaller.appspot.com/bug?extid=3667d719a932ebc28119 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-c4b9570c.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/f4f88f09e44f/vmlinux-c4b9570c.xz kernel image: https://storage.googleapis.com/syzbot-assets/bb4658fd4384/bzImage-c4b9570c.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+3667d719a932ebc28119@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.13.0-syzkaller-02526-gc4b9570cfb63 #0 Not tainted ------------------------------------------------------ syz.2.21908/20249 is trying to acquire lock: ffff88804fb90dd8 (sk_lock-AF_SMC){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1623 [inline] ffff88804fb90dd8 (sk_lock-AF_SMC){+.+.}-{0:0}, at: smc_shutdown+0x65/0x7f0 net/smc/af_smc.c:2927 but task is already holding lock: ffff88806efb3c70 (&nsock->tx_lock){+.+.}-{4:4}, at: sock_shutdown+0x16f/0x280 drivers/block/nbd.c:410 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #7 (&nsock->tx_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 sock_shutdown+0x16f/0x280 drivers/block/nbd.c:410 nbd_clear_sock drivers/block/nbd.c:1415 [inline] nbd_clear_sock_ioctl drivers/block/nbd.c:1553 [inline] __nbd_ioctl drivers/block/nbd.c:1581 [inline] nbd_ioctl+0x49b/0xd60 drivers/block/nbd.c:1641 compat_blkdev_ioctl+0x2f7/0x750 block/ioctl.c:749 __do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004 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 -> #6 (&nbd->config_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 refcount_dec_and_mutex_lock+0x51/0xc0 lib/refcount.c:118 nbd_config_put+0x31/0x750 drivers/block/nbd.c:1422 nbd_release+0xb7/0x190 drivers/block/nbd.c:1734 blkdev_put_whole+0xad/0xf0 block/bdev.c:679 bdev_release+0x47e/0x6d0 block/bdev.c:1102 blkdev_release+0x15/0x20 block/fops.c:660 __fput+0x3f8/0xb60 fs/file_table.c:450 __fput_sync+0xa1/0xc0 fs/file_table.c:536 __do_sys_close fs/open.c:1547 [inline] __se_sys_close fs/open.c:1532 [inline] __x64_sys_close+0x86/0x100 fs/open.c:1532 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 -> #5 (&disk->open_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 bdev_open+0x41a/0xe20 block/bdev.c:903 bdev_file_open_by_dev block/bdev.c:1017 [inline] bdev_file_open_by_dev+0x17d/0x210 block/bdev.c:992 disk_scan_partitions+0x1ed/0x320 block/genhd.c:374 add_disk_fwnode+0x1006/0x1320 block/genhd.c:526 pmem_attach_disk+0x9a1/0x13e0 drivers/nvdimm/pmem.c:576 nd_pmem_probe+0x1a9/0x1f0 drivers/nvdimm/pmem.c:649 nvdimm_bus_probe+0x169/0x5d0 drivers/nvdimm/bus.c:94 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:658 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:800 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830 __driver_attach+0x283/0x580 drivers/base/dd.c:1216 bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:370 bus_add_driver+0x2e9/0x690 drivers/base/bus.c:675 driver_register+0x15c/0x4b0 drivers/base/driver.c:246 __nd_driver_register+0x103/0x1a0 drivers/nvdimm/bus.c:622 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+0x58f/0x8b0 init/main.c:1578 kernel_init+0x1c/0x2b0 init/main.c:1467 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #4 (&nvdimm_namespace_key){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 device_lock include/linux/device.h:1014 [inline] uevent_show+0x188/0x3b0 drivers/base/core.c:2729 dev_attr_show+0x53/0xe0 drivers/base/core.c:2423 sysfs_kf_seq_show+0x223/0x3e0 fs/sysfs/file.c:59 seq_read_iter+0x4f4/0x12b0 fs/seq_file.c:230 kernfs_fop_read_iter+0x414/0x580 fs/kernfs/file.c:279 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x87f/0xbe0 fs/read_write.c:565 ksys_read+0x12b/0x250 fs/read_write.c:708 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 -> #3 (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:794 [inline] device_remove_file drivers/base/core.c:3047 [inline] device_remove_file drivers/base/core.c:3043 [inline] device_del+0x381/0x9f0 drivers/base/core.c:3852 unregister_netdevice_many_notify+0x105d/0x1e60 net/core/dev.c:11581 unregister_netdevice_many net/core/dev.c:11609 [inline] unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11481 unregister_netdevice include/linux/netdevice.h:3192 [inline] unregister_netdev+0x1c/0x30 net/core/dev.c:11627 slcan_close+0x76/0x1a0 drivers/net/can/slcan/slcan-core.c:866 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+0x116/0x2a0 drivers/tty/tty_ldisc.c:781 tty_release_struct+0x23/0xe0 drivers/tty/tty_io.c:1690 tty_release+0xe25/0x1410 drivers/tty/tty_io.c:1861 __fput+0x3f8/0xb60 fs/file_table.c:450 task_work_run+0x14e/0x250 kernel/task_work.c:239 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:329 [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 -> #2 (rtnl_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 start_sync_thread+0x12d/0x2740 net/netfilter/ipvs/ip_vs_sync.c:1761 do_ip_vs_set_ctl+0x41c/0x1070 net/netfilter/ipvs/ip_vs_ctl.c:2732 nf_setsockopt+0x8a/0xf0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424 tcp_setsockopt+0xa4/0x100 net/ipv4/tcp.c:4030 smc_setsockopt+0x1b4/0xc00 net/smc/af_smc.c:3078 do_sock_setsockopt+0x222/0x480 net/socket.c:2313 __sys_setsockopt+0x1a0/0x230 net/socket.c:2338 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __ia32_sys_setsockopt+0xbc/0x160 net/socket.c:2341 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 -> #1 (&smc->clcsock_release_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 smc_switch_to_fallback+0x2d/0xa00 net/smc/af_smc.c:903 smc_setsockopt+0xa7b/0xc00 net/smc/af_smc.c:3101 do_sock_setsockopt+0x222/0x480 net/socket.c:2313 __sys_setsockopt+0x1a0/0x230 net/socket.c:2338 __do_sys_setsockopt net/socket.c:2344 [inline] __se_sys_setsockopt net/socket.c:2341 [inline] __ia32_sys_setsockopt+0xbc/0x160 net/socket.c:2341 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:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3625 lock_sock include/net/sock.h:1623 [inline] smc_shutdown+0x65/0x7f0 net/smc/af_smc.c:2927 nbd_mark_nsock_dead+0xae/0x5d0 drivers/block/nbd.c:318 sock_shutdown+0x17c/0x280 drivers/block/nbd.c:411 nbd_clear_sock drivers/block/nbd.c:1415 [inline] nbd_clear_sock_ioctl drivers/block/nbd.c:1553 [inline] __nbd_ioctl drivers/block/nbd.c:1581 [inline] nbd_ioctl+0x49b/0xd60 drivers/block/nbd.c:1641 compat_blkdev_ioctl+0x2f7/0x750 block/ioctl.c:749 __do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004 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 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 *** 2 locks held by syz.2.21908/20249: #0: ffff888024364998 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x151/0xd60 drivers/block/nbd.c:1634 #1: ffff88806efb3c70 (&nsock->tx_lock){+.+.}-{4:4}, at: sock_shutdown+0x16f/0x280 drivers/block/nbd.c:410 stack backtrace: CPU: 3 UID: 0 PID: 20249 Comm: syz.2.21908 Not tainted 6.13.0-syzkaller-02526-gc4b9570cfb63 #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: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x490/0x760 kernel/locking/lockdep.c:2076 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851 lock_sock_nested+0x3a/0xf0 net/core/sock.c:3625 lock_sock include/net/sock.h:1623 [inline] smc_shutdown+0x65/0x7f0 net/smc/af_smc.c:2927 nbd_mark_nsock_dead+0xae/0x5d0 drivers/block/nbd.c:318 sock_shutdown+0x17c/0x280 drivers/block/nbd.c:411 nbd_clear_sock drivers/block/nbd.c:1415 [inline] nbd_clear_sock_ioctl drivers/block/nbd.c:1553 [inline] __nbd_ioctl drivers/block/nbd.c:1581 [inline] nbd_ioctl+0x49b/0xd60 drivers/block/nbd.c:1641 compat_blkdev_ioctl+0x2f7/0x750 block/ioctl.c:749 __do_compat_sys_ioctl+0x1cb/0x2c0 fs/ioctl.c:1004 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 RIP: 0023:0xf7f0f579 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:00000000f506655c EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000000ab04 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> block nbd2: 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 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
