====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.1.1053/10273 is trying to acquire lock: ffff88801d732460 (sb_writers#5){.+.+}-{0:0}, at: lookup_open+0x150/0x1990 fs/namei.c:4451 but task is already holding lock: ffff8880696df068 (&subsys->lock){+.+.}-{4:4}, at: nvmet_ns_enable+0x4f/0x650 drivers/nvme/target/core.c:583 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&subsys->lock){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5942 [inline] lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x1a4/0x1bd0 kernel/locking/mutex.c:821 nvmet_ns_device_path_store+0x57/0x1c0 drivers/nvme/target/configfs.c:538 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6af/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #2 (&p->frag_sem){++++}-{4:4}: lock_acquire kernel/locking/lockdep.c:5942 [inline] lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899 down_read+0x99/0x4c0 kernel/locking/rwsem.c:1574 __configfs_open_file+0xe8/0x9c0 fs/configfs/file.c:304 do_dentry_open+0x6ab/0x14d0 fs/open.c:996 vfs_open+0x82/0x3f0 fs/open.c:1101 dentry_open+0x71/0xd0 fs/open.c:1124 ima_calc_file_hash+0xe1/0x380 security/integrity/ima/ima_crypto.c:269 ima_collect_measurement+0x94f/0xb30 security/integrity/ima/ima_api.c:300 process_measurement+0xdfe/0x2350 security/integrity/ima/ima_main.c:425 ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685 security_file_post_open+0xc4/0x210 security/security.c:2755 do_open fs/namei.c:4839 [inline] path_openat+0x5cd/0x2440 fs/namei.c:5000 do_file_open+0x20e/0x430 fs/namei.c:5029 do_sys_openat2+0x10f/0x1e0 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_compat_sys_openat fs/open.c:1485 [inline] __se_compat_sys_openat fs/open.c:1483 [inline] __ia32_compat_sys_openat+0x12d/0x210 fs/open.c:1483 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #1 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5942 [inline] lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x1a4/0x1bd0 kernel/locking/mutex.c:821 process_measurement+0x5ab/0x2350 security/integrity/ima/ima_main.c:319 ima_file_check+0xcc/0x120 security/integrity/ima/ima_main.c:685 security_file_post_open+0xc4/0x210 security/security.c:2755 do_open fs/namei.c:4839 [inline] path_openat+0x5cd/0x2440 fs/namei.c:5000 do_file_open+0x20e/0x430 fs/namei.c:5029 do_sys_openat2+0x10f/0x1e0 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1434 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x121/0x770 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sb_writers#5){.+.+}-{0:0}: check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3209 check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x1528/0x1f40 kernel/locking/lockdep.c:5288 lock_acquire kernel/locking/lockdep.c:5942 [inline] lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_write include/linux/fs/super.h:125 [inline] mnt_want_write+0x6f/0x420 fs/namespace.c:494 lookup_open+0x150/0x1990 fs/namei.c:4451 open_last_lookups fs/namei.c:4767 [inline] path_openat+0xa2c/0x2440 fs/namei.c:4997 do_file_open+0x20e/0x430 fs/namei.c:5029 file_open_name+0x1c3/0x3e0 fs/open.c:1375 filp_open+0x2e/0x50 fs/open.c:1392 nvmet_file_ns_enable+0x95/0x420 drivers/nvme/target/io-cmd-file.c:41 nvmet_ns_enable+0x43b/0x650 drivers/nvme/target/core.c:601 nvmet_ns_enable_store+0x11e/0x160 drivers/nvme/target/configfs.c:737 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6af/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316 entry_SYSENTER_compat_after_hwframe+0x84/0x8e other info that might help us debug this: Chain exists of: sb_writers#5 --> &p->frag_sem --> &subsys->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&subsys->lock); lock(&p->frag_sem); lock(&subsys->lock); rlock(sb_writers#5); *** DEADLOCK *** locks held by syz.1.1053/10273: 6, last CPU#0: #0: ffff8880288e7970 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259 #1: ffff888022890460 (sb_writers#12){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739 #2: ffff88802625d280 (&buffer->mutex){+.+.}-{4:4}, at: configfs_write_iter+0x76/0x4e0 fs/configfs/file.c:226 #3: ffff8880501cfd70 (&p->frag_sem){++++}-{4:4}, at: flush_write_buffer fs/configfs/file.c:205 [inline] #3: ffff8880501cfd70 (&p->frag_sem){++++}-{4:4}, at: configfs_write_iter+0x218/0x4e0 fs/configfs/file.c:229 #4: ffffffff8ff5bd28 (nvmet_config_sem){+.+.}-{4:4}, at: nvmet_ns_enable_store+0xa5/0x160 drivers/nvme/target/configfs.c:735 #5: ffff8880696df068 (&subsys->lock){+.+.}-{4:4}, at: nvmet_ns_enable+0x4f/0x650 drivers/nvme/target/core.c:583 stack backtrace: CPU: 0 UID: 0 PID: 10273 Comm: syz.1.1053 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_circular_bug.cold+0x178/0x1be kernel/locking/lockdep.c:2087 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2219 check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3209 check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x1528/0x1f40 kernel/locking/lockdep.c:5288 lock_acquire kernel/locking/lockdep.c:5942 [inline] lock_acquire+0x1d1/0x380 kernel/locking/lockdep.c:5899 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_write include/linux/fs/super.h:125 [inline] mnt_want_write+0x6f/0x420 fs/namespace.c:494 lookup_open+0x150/0x1990 fs/namei.c:4451 open_last_lookups fs/namei.c:4767 [inline] path_openat+0xa2c/0x2440 fs/namei.c:4997 do_file_open+0x20e/0x430 fs/namei.c:5029 file_open_name+0x1c3/0x3e0 fs/open.c:1375 filp_open+0x2e/0x50 fs/open.c:1392 nvmet_file_ns_enable+0x95/0x420 drivers/nvme/target/io-cmd-file.c:41 nvmet_ns_enable+0x43b/0x650 drivers/nvme/target/core.c:601 nvmet_ns_enable_store+0x11e/0x160 drivers/nvme/target/configfs.c:737 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6af/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fe3fec Code: Unable to access opcode bytes at 0xf7fe3fc2. RSP: 002b:00000000f54a650c EFLAGS: 00000292 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 0000000080000600 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 nvmet: failed to open file ./file0: (-2) nvmet: Disable port '1' before changing attribute in nvmet_addr_trtype_store nvmet: Disable port '1' before changing attribute in nvmet_addr_adrfam_store nvmet: Disable port '1' before changing attribute in nvmet_addr_traddr_store nvme nvme0: NVME-FC{0}: new ctrl: NQN "testsubsys", hostnqn: nqn.2014-08.org.nvmexpress:uuid:6b5ef04c-f198-4c8a-a171-11047b4071cf