====================================================== WARNING: possible circular locking dependency detected 6.3.0-rc7-syzkaller-g14f8db1c0f9a #0 Not tainted ------------------------------------------------------ syz-executor.2/25786 is trying to acquire lock: ffff0000e1772968 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x240 fs/quota/dquot.c:479 but task is already holding lock: ffff00014e7320a0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x794/0x1884 fs/ext4/inode.c:644 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&ei->i_data_sem/2){++++}-{3:3}: down_read+0x50/0x6c kernel/locking/rwsem.c:1520 ext4_map_blocks+0x2ac/0x1884 fs/ext4/inode.c:574 ext4_getblk+0x198/0x6ec fs/ext4/inode.c:863 ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:919 ext4_quota_write+0x230/0x54c fs/ext4/super.c:7135 write_blk fs/quota/quota_tree.c:64 [inline] get_free_dqblk+0x284/0x570 fs/quota/quota_tree.c:130 do_insert_tree+0x200/0x1438 fs/quota/quota_tree.c:340 do_insert_tree+0x534/0x1438 fs/quota/quota_tree.c:375 dq_insert_tree fs/quota/quota_tree.c:401 [inline] qtree_write_dquot+0x318/0x488 fs/quota/quota_tree.c:420 v2_write_dquot+0xf4/0x188 fs/quota/quota_v2.c:358 dquot_acquire+0x2c4/0x5c4 fs/quota/dquot.c:444 ext4_acquire_dquot+0x270/0x398 fs/ext4/super.c:6770 dqget+0x844/0xc48 fs/quota/dquot.c:914 __dquot_initialize+0x344/0xb54 fs/quota/dquot.c:1492 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1550 ext4_create+0xb4/0x480 fs/ext4/namei.c:2801 lookup_open fs/namei.c:3416 [inline] open_last_lookups fs/namei.c:3484 [inline] path_openat+0xf80/0x27f8 fs/namei.c:3712 do_filp_open+0x1bc/0x3cc fs/namei.c:3742 do_sys_openat2+0x128/0x3d8 fs/open.c:1348 do_sys_open fs/open.c:1364 [inline] __do_sys_openat fs/open.c:1380 [inline] __se_sys_openat fs/open.c:1375 [inline] __arm64_sys_openat+0x1f0/0x240 fs/open.c:1375 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x4c/0x15c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 -> #1 (&s->s_dquot.dqio_sem){++++}-{3:3}: down_read+0x50/0x6c kernel/locking/rwsem.c:1520 v2_read_dquot+0x50/0x11c fs/quota/quota_v2.c:332 dquot_acquire+0x130/0x5c4 fs/quota/dquot.c:435 ext4_acquire_dquot+0x270/0x398 fs/ext4/super.c:6770 dqget+0x844/0xc48 fs/quota/dquot.c:914 __dquot_initialize+0x344/0xb54 fs/quota/dquot.c:1492 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1550 ext4_create+0xb4/0x480 fs/ext4/namei.c:2801 lookup_open fs/namei.c:3416 [inline] open_last_lookups fs/namei.c:3484 [inline] path_openat+0xf80/0x27f8 fs/namei.c:3712 do_filp_open+0x1bc/0x3cc fs/namei.c:3742 do_sys_openat2+0x128/0x3d8 fs/open.c:1348 do_sys_open fs/open.c:1364 [inline] __do_sys_openat fs/open.c:1380 [inline] __se_sys_openat fs/open.c:1375 [inline] __arm64_sys_openat+0x1f0/0x240 fs/open.c:1375 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x4c/0x15c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 -> #0 (&dquot->dq_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain kernel/locking/lockdep.c:3832 [inline] __lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5056 lock_acquire+0x238/0x718 kernel/locking/lockdep.c:5669 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 dquot_commit+0x54/0x240 fs/quota/dquot.c:479 ext4_write_dquot+0x1b4/0x288 fs/ext4/super.c:6754 ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6802 mark_dquot_dirty fs/quota/dquot.c:346 [inline] mark_all_dquot_dirty fs/quota/dquot.c:384 [inline] __dquot_alloc_space+0x488/0xb00 fs/quota/dquot.c:1722 dquot_alloc_space_nodirty include/linux/quotaops.h:300 [inline] dquot_alloc_space include/linux/quotaops.h:313 [inline] dquot_alloc_block include/linux/quotaops.h:337 [inline] ext4_mb_new_blocks+0xed4/0x43dc fs/ext4/mballoc.c:5571 ext4_ext_map_blocks+0x1378/0x5f50 fs/ext4/extents.c:4286 ext4_map_blocks+0x828/0x1884 fs/ext4/inode.c:651 ext4_getblk+0x198/0x6ec fs/ext4/inode.c:863 ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:919 ext4_append+0x260/0x4cc fs/ext4/namei.c:83 ext4_init_new_dir+0x294/0x8e4 fs/ext4/namei.c:2955 ext4_mkdir+0x3d4/0xa64 fs/ext4/namei.c:3001 vfs_mkdir+0x240/0x3a8 fs/namei.c:4038 do_mkdirat+0x20c/0x610 fs/namei.c:4061 __do_sys_mkdirat fs/namei.c:4076 [inline] __se_sys_mkdirat fs/namei.c:4074 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4074 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x4c/0x15c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 other info that might help us debug this: Chain exists of: &dquot->dq_lock --> &s->s_dquot.dqio_sem --> &ei->i_data_sem/2 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->i_data_sem/2); lock(&s->s_dquot.dqio_sem); lock(&ei->i_data_sem/2); lock(&dquot->dq_lock); *** DEADLOCK *** 4 locks held by syz-executor.2/25786: #0: ffff00013744a460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:394 #1: ffff00014e45f258 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline] #1: ffff00014e45f258 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x200/0x464 fs/namei.c:3808 #2: ffff00014e7320a0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x794/0x1884 fs/ext4/inode.c:644 #3: ffff80001606fae8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:326 stack backtrace: CPU: 0 PID: 25786 Comm: syz-executor.2 Not tainted 6.3.0-rc7-syzkaller-g14f8db1c0f9a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2056 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain kernel/locking/lockdep.c:3832 [inline] __lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5056 lock_acquire+0x238/0x718 kernel/locking/lockdep.c:5669 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 dquot_commit+0x54/0x240 fs/quota/dquot.c:479 ext4_write_dquot+0x1b4/0x288 fs/ext4/super.c:6754 ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6802 mark_dquot_dirty fs/quota/dquot.c:346 [inline] mark_all_dquot_dirty fs/quota/dquot.c:384 [inline] __dquot_alloc_space+0x488/0xb00 fs/quota/dquot.c:1722 dquot_alloc_space_nodirty include/linux/quotaops.h:300 [inline] dquot_alloc_space include/linux/quotaops.h:313 [inline] dquot_alloc_block include/linux/quotaops.h:337 [inline] ext4_mb_new_blocks+0xed4/0x43dc fs/ext4/mballoc.c:5571 ext4_ext_map_blocks+0x1378/0x5f50 fs/ext4/extents.c:4286 ext4_map_blocks+0x828/0x1884 fs/ext4/inode.c:651 ext4_getblk+0x198/0x6ec fs/ext4/inode.c:863 ext4_bread+0x3c/0x1b0 fs/ext4/inode.c:919 ext4_append+0x260/0x4cc fs/ext4/namei.c:83 ext4_init_new_dir+0x294/0x8e4 fs/ext4/namei.c:2955 ext4_mkdir+0x3d4/0xa64 fs/ext4/namei.c:3001 vfs_mkdir+0x240/0x3a8 fs/namei.c:4038 do_mkdirat+0x20c/0x610 fs/namei.c:4061 __do_sys_mkdirat fs/namei.c:4076 [inline] __se_sys_mkdirat fs/namei.c:4074 [inline] __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4074 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x4c/0x15c arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591