syzbot

======================================================
WARNING: possible circular locking dependency detected
5.15.124-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.1/11846 is trying to acquire lock:
ffff88807e665088 (&mk->mk_sem){.+.+}-{3:3}, at: setup_file_encryption_key fs/crypto/keysetup.c:456 [inline]
ffff88807e665088 (&mk->mk_sem){.+.+}-{3:3}, at: fscrypt_setup_encryption_info+0x5b6/0x13a0 fs/crypto/keysetup.c:553

but task is already holding lock:
ffff88807e1aabd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x314/0x12f0 fs/ext4/migrate.c:438

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #5 (&sbi->s_writepages_rwsem){++++}-{0:0}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       percpu_down_write+0x52/0x2d0 kernel/locking/percpu-rwsem.c:217
       ext4_change_inode_journal_flag+0x1a0/0x6e0 fs/ext4/inode.c:6040
       ext4_ioctl_setflags fs/ext4/ioctl.c:448 [inline]
       ext4_fileattr_set+0xdf4/0x1750 fs/ext4/ioctl.c:765
       vfs_fileattr_set+0x8f3/0xd30 fs/ioctl.c:700
       ioctl_setflags fs/ioctl.c:732 [inline]
       do_vfs_ioctl+0x1d85/0x2b70 fs/ioctl.c:843
       __do_sys_ioctl fs/ioctl.c:872 [inline]
       __se_sys_ioctl+0x81/0x160 fs/ioctl.c:860
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

-> #4 (mapping.invalidate_lock){++++}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       down_read+0x45/0x2e0 kernel/locking/rwsem.c:1488
       filemap_invalidate_lock_shared include/linux/fs.h:842 [inline]
       filemap_fault+0x708/0x1470 mm/filemap.c:3072
       __do_fault+0x139/0x340 mm/memory.c:3898
       do_cow_fault mm/memory.c:4263 [inline]
       do_fault mm/memory.c:4364 [inline]
       handle_pte_fault mm/memory.c:4621 [inline]
       __handle_mm_fault mm/memory.c:4756 [inline]
       handle_mm_fault+0x30da/0x5950 mm/memory.c:4854
       do_user_addr_fault arch/x86/mm/fault.c:1397 [inline]
       handle_page_fault arch/x86/mm/fault.c:1485 [inline]
       exc_page_fault+0x271/0x740 arch/x86/mm/fault.c:1541
       asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568

-> #3 (&mm->mmap_lock#2){++++}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       down_write+0x97/0x170 kernel/locking/rwsem.c:1541
       mmap_write_lock include/linux/mmap_lock.h:71 [inline]
       mpol_rebind_mm+0x34/0x2b0 mm/mempolicy.c:381
       cpuset_attach+0x393/0x540 kernel/cgroup/cpuset.c:2289
       cgroup_migrate_execute+0x7fb/0x10e0 kernel/cgroup/cgroup.c:2573
       cgroup_attach_task+0x58a/0x840 kernel/cgroup/cgroup.c:2868
       __cgroup1_procs_write+0x2ec/0x460 kernel/cgroup/cgroup-v1.c:528
       cgroup_file_write+0x2ac/0x670 kernel/cgroup/cgroup.c:3946
       kernfs_fop_write_iter+0x3a2/0x4f0 fs/kernfs/file.c:296
       call_write_iter include/linux/fs.h:2103 [inline]
       new_sync_write fs/read_write.c:507 [inline]
       vfs_write+0xacf/0xe50 fs/read_write.c:594
       ksys_write+0x1a2/0x2c0 fs/read_write.c:647
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

-> #2 (&cpuset_rwsem){++++}-{0:0}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       cpuset_read_lock+0x40/0x150 kernel/cgroup/cpuset.c:356
       __sched_setscheduler+0x626/0x1df0 kernel/sched/core.c:7409
       _sched_setscheduler kernel/sched/core.c:7586 [inline]
       sched_setscheduler_nocheck+0x187/0x2d0 kernel/sched/core.c:7633
       __kthread_create_on_node+0x31b/0x3f0 kernel/kthread.c:413
       kthread_create_on_node+0xda/0x120 kernel/kthread.c:453
       cryptomgr_schedule_test crypto/algboss.c:219 [inline]
       cryptomgr_notify+0x125/0xc70 crypto/algboss.c:240
       notifier_call_chain kernel/notifier.c:83 [inline]
       blocking_notifier_call_chain+0x104/0x1b0 kernel/notifier.c:318
       crypto_probing_notify+0x21/0x70 crypto/api.c:251
       crypto_wait_for_test+0x3e/0xd0 crypto/algapi.c:396
       crypto_register_alg+0x25b/0x330 crypto/algapi.c:429
       do_one_initcall+0x22b/0x7a0 init/main.c:1306
       do_initcall_level+0x157/0x207 init/main.c:1379
       do_initcalls+0x49/0x86 init/main.c:1395
       kernel_init_freeable+0x43c/0x5c5 init/main.c:1619
       kernel_init+0x19/0x290 init/main.c:1510
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

-> #1 ((crypto_chain).rwsem){++++}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       down_read+0x45/0x2e0 kernel/locking/rwsem.c:1488
       blocking_notifier_call_chain+0x5e/0x1b0 kernel/notifier.c:317
       crypto_probing_notify crypto/api.c:251 [inline]
       crypto_alg_mod_lookup+0x4e6/0x710 crypto/api.c:281
       crypto_find_alg crypto/api.c:490 [inline]
       crypto_alloc_tfm_node+0x12c/0x350 crypto/api.c:527
       cryptd_alloc_skcipher+0xde/0x1f0 crypto/cryptd.c:916
       simd_skcipher_init+0x63/0x130 crypto/simd.c:122
       crypto_create_tfm_node+0x105/0x360 crypto/api.c:457
       crypto_alloc_tfm_node+0x15d/0x350 crypto/api.c:533
       fscrypt_allocate_skcipher fs/crypto/keysetup.c:84 [inline]
       fscrypt_prepare_key+0x89/0x360 fs/crypto/keysetup.c:135
       fscrypt_set_per_file_enc_key fs/crypto/keysetup.c:160 [inline]
       fscrypt_setup_v2_file_key fs/crypto/keysetup.c:349 [inline]
       setup_file_encryption_key fs/crypto/keysetup.c:474 [inline]
       fscrypt_setup_encryption_info+0xcf4/0x13a0 fs/crypto/keysetup.c:553
       fscrypt_prepare_new_inode+0x208/0x2f0 fs/crypto/keysetup.c:698
       __ext4_new_inode+0x85f/0x4430 fs/ext4/ialloc.c:988
       ext4_mkdir+0x421/0xce0 fs/ext4/namei.c:3012
       vfs_mkdir+0x419/0x640 fs/namei.c:3994
       do_mkdirat+0x260/0x520 fs/namei.c:4019
       __do_sys_mkdir fs/namei.c:4039 [inline]
       __se_sys_mkdir fs/namei.c:4037 [inline]
       __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4037
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

-> #0 (&mk->mk_sem){.+.+}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       down_read+0x45/0x2e0 kernel/locking/rwsem.c:1488
       setup_file_encryption_key fs/crypto/keysetup.c:456 [inline]
       fscrypt_setup_encryption_info+0x5b6/0x13a0 fs/crypto/keysetup.c:553
       fscrypt_prepare_new_inode+0x208/0x2f0 fs/crypto/keysetup.c:698
       __ext4_new_inode+0x85f/0x4430 fs/ext4/ialloc.c:988
       ext4_ext_migrate+0x679/0x12f0 fs/ext4/migrate.c:456
       ext4_ioctl_setflags fs/ext4/ioctl.c:455 [inline]
       ext4_fileattr_set+0xef6/0x1750 fs/ext4/ioctl.c:765
       vfs_fileattr_set+0x8f3/0xd30 fs/ioctl.c:700
       ioctl_setflags fs/ioctl.c:732 [inline]
       do_vfs_ioctl+0x1d85/0x2b70 fs/ioctl.c:843
       __do_sys_ioctl fs/ioctl.c:872 [inline]
       __se_sys_ioctl+0x81/0x160 fs/ioctl.c:860
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

other info that might help us debug this:

Chain exists of:
  &mk->mk_sem --> mapping.invalidate_lock --> &sbi->s_writepages_rwsem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sbi->s_writepages_rwsem);
                               lock(mapping.invalidate_lock);
                               lock(&sbi->s_writepages_rwsem);
  lock(&mk->mk_sem);

 *** DEADLOCK ***

3 locks held by syz-executor.1/11846:
 #0: ffff8880793ee460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write_file+0x5a/0x1f0 fs/namespace.c:421
 #1: ffff8880333c67a0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff8880333c67a0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_fileattr_set+0x135/0xd30 fs/ioctl.c:685
 #2: ffff88807e1aabd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x314/0x12f0 fs/ext4/migrate.c:438

stack backtrace:
CPU: 0 PID: 11846 Comm: syz-executor.1 Not tainted 5.15.124-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
 down_read+0x45/0x2e0 kernel/locking/rwsem.c:1488
 setup_file_encryption_key fs/crypto/keysetup.c:456 [inline]
 fscrypt_setup_encryption_info+0x5b6/0x13a0 fs/crypto/keysetup.c:553
 fscrypt_prepare_new_inode+0x208/0x2f0 fs/crypto/keysetup.c:698
 __ext4_new_inode+0x85f/0x4430 fs/ext4/ialloc.c:988
 ext4_ext_migrate+0x679/0x12f0 fs/ext4/migrate.c:456
 ext4_ioctl_setflags fs/ext4/ioctl.c:455 [inline]
 ext4_fileattr_set+0xef6/0x1750 fs/ext4/ioctl.c:765
 vfs_fileattr_set+0x8f3/0xd30 fs/ioctl.c:700
 ioctl_setflags fs/ioctl.c:732 [inline]
 do_vfs_ioctl+0x1d85/0x2b70 fs/ioctl.c:843
 __do_sys_ioctl fs/ioctl.c:872 [inline]
 __se_sys_ioctl+0x81/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f2f9a35aae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2f988dc0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f2f9a479f80 RCX: 00007f2f9a35aae9
RDX: 0000000020000000 RSI: 0000000040086602 RDI: 0000000000000005
RBP: 00007f2f9a3a647a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f2f9a479f80 R15: 00007ffd32768fd8
 </TASK>