====================================================== WARNING: possible circular locking dependency detected 6.3.0-rc7-syzkaller-g14f8db1c0f9a #0 Not tainted ------------------------------------------------------ syz-executor.1/11078 is trying to acquire lock: ffff0001ffb680a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x240 fs/quota/dquot.c:479 but task is already holding lock: ffff0000e11452c8 (&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 do_insert_tree+0x534/0x1438 fs/quota/quota_tree.c:375 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_process_orphan+0x5c/0x2b8 fs/ext4/orphan.c:329 ext4_orphan_cleanup+0x968/0x1140 fs/ext4/orphan.c:474 __ext4_fill_super fs/ext4/super.c:5509 [inline] ext4_fill_super+0x644c/0x6a30 fs/ext4/super.c:5637 get_tree_bdev+0x360/0x54c fs/super.c:1303 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5668 vfs_get_tree+0x90/0x274 fs/super.c:1510 do_new_mount+0x25c/0x8c8 fs/namespace.c:3042 path_mount+0x590/0xe04 fs/namespace.c:3372 do_mount fs/namespace.c:3385 [inline] __do_sys_mount fs/namespace.c:3594 [inline] __se_sys_mount fs/namespace.c:3571 [inline] __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3571 __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+0x2cc/0xb54 fs/quota/dquot.c:1492 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1550 ext4_process_orphan+0x5c/0x2b8 fs/ext4/orphan.c:329 ext4_orphan_cleanup+0x968/0x1140 fs/ext4/orphan.c:474 __ext4_fill_super fs/ext4/super.c:5509 [inline] ext4_fill_super+0x644c/0x6a30 fs/ext4/super.c:5637 get_tree_bdev+0x360/0x54c fs/super.c:1303 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5668 vfs_get_tree+0x90/0x274 fs/super.c:1510 do_new_mount+0x25c/0x8c8 fs/namespace.c:3042 path_mount+0x590/0xe04 fs/namespace.c:3372 do_mount fs/namespace.c:3385 [inline] __do_sys_mount fs/namespace.c:3594 [inline] __se_sys_mount fs/namespace.c:3571 [inline] __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3571 __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_get_block+0x1c8/0x5f0 fs/ext4/inode.c:807 ext4_get_block+0x4c/0x60 fs/ext4/inode.c:824 ext4_block_write_begin+0x52c/0x14ec fs/ext4/inode.c:1097 ext4_write_begin+0x5f8/0x12f8 ext4_da_write_begin+0x350/0x9b0 fs/ext4/inode.c:3057 generic_perform_write+0x278/0x55c mm/filemap.c:3926 ext4_buffered_write_iter+0x2e0/0x538 fs/ext4/file.c:289 ext4_file_write_iter+0x188/0x16c8 call_write_iter include/linux/fs.h:1851 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x610/0x914 fs/read_write.c:584 ksys_write+0x15c/0x26c fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __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 *** 5 locks held by syz-executor.1/11078: #0: ffff0000ca5585e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xd8/0x104 fs/file.c:1047 #1: ffff00013b362460 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x244/0x914 fs/read_write.c:580 #2: ffff0000e1145440 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #2: ffff0000e1145440 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0x9c/0x538 fs/ext4/file.c:283 #3: ffff0000e11452c8 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x794/0x1884 fs/ext4/inode.c:644 #4: ffff80001606fae8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:326 stack backtrace: CPU: 1 PID: 11078 Comm: syz-executor.1 Not tainted 6.3.0-rc7-syzkaller-g14f8db1c0f9a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 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_get_block+0x1c8/0x5f0 fs/ext4/inode.c:807 ext4_get_block+0x4c/0x60 fs/ext4/inode.c:824 ext4_block_write_begin+0x52c/0x14ec fs/ext4/inode.c:1097 ext4_write_begin+0x5f8/0x12f8 ext4_da_write_begin+0x350/0x9b0 fs/ext4/inode.c:3057 generic_perform_write+0x278/0x55c mm/filemap.c:3926 ext4_buffered_write_iter+0x2e0/0x538 fs/ext4/file.c:289 ext4_file_write_iter+0x188/0x16c8 call_write_iter include/linux/fs.h:1851 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x610/0x914 fs/read_write.c:584 ksys_write+0x15c/0x26c fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __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