====================================================== WARNING: possible circular locking dependency detected 6.3.0-syzkaller-00113-g1a0beef98b58 #0 Not tainted ------------------------------------------------------ syz-executor.3/9283 is trying to acquire lock: ffff8880796035a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5b/0x520 fs/quota/dquot.c:479 but task is already holding lock: ffff888076d3f0e0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x980/0x1cf0 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}: lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669 down_read+0x3d/0x50 kernel/locking/rwsem.c:1520 ext4_map_blocks+0x38e/0x1cf0 fs/ext4/inode.c:574 ext4_getblk+0x1ef/0x7c0 fs/ext4/inode.c:863 ext4_bread+0x2e/0x180 fs/ext4/inode.c:919 ext4_quota_read+0x1a5/0x2c0 fs/ext4/super.c:7089 read_blk fs/quota/quota_tree.c:55 [inline] find_tree_dqentry+0x18c/0xbd0 fs/quota/quota_tree.c:624 find_tree_dqentry+0x486/0xbd0 fs/quota/quota_tree.c:640 find_tree_dqentry+0x486/0xbd0 fs/quota/quota_tree.c:640 find_tree_dqentry+0x486/0xbd0 fs/quota/quota_tree.c:640 find_dqentry fs/quota/quota_tree.c:652 [inline] qtree_read_dquot+0x143/0x650 fs/quota/quota_tree.c:672 v2_read_dquot+0xc2/0x110 fs/quota/quota_v2.c:333 dquot_acquire+0x18c/0x680 fs/quota/dquot.c:435 ext4_acquire_dquot+0x2e6/0x400 fs/ext4/super.c:6770 dqget+0x98f/0xdb0 fs/quota/dquot.c:914 __dquot_initialize+0x2dd/0xe20 fs/quota/dquot.c:1492 ext4_process_orphan+0x57/0x2d0 fs/ext4/orphan.c:329 ext4_orphan_cleanup+0xb21/0x13c0 fs/ext4/orphan.c:474 __ext4_fill_super fs/ext4/super.c:5509 [inline] ext4_fill_super+0x8239/0x8990 fs/ext4/super.c:5637 get_tree_bdev+0x402/0x620 fs/super.c:1303 vfs_get_tree+0x8c/0x270 fs/super.c:1510 do_new_mount+0x28f/0xae0 fs/namespace.c:3042 do_mount fs/namespace.c:3385 [inline] __do_sys_mount fs/namespace.c:3594 [inline] __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3571 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&s->s_dquot.dqio_sem){++++}-{3:3}: lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669 down_read+0x3d/0x50 kernel/locking/rwsem.c:1520 v2_read_dquot+0x4e/0x110 fs/quota/quota_v2.c:332 dquot_acquire+0x18c/0x680 fs/quota/dquot.c:435 ext4_acquire_dquot+0x2e6/0x400 fs/ext4/super.c:6770 dqget+0x98f/0xdb0 fs/quota/dquot.c:914 __dquot_initialize+0x2dd/0xe20 fs/quota/dquot.c:1492 ext4_create+0xb5/0x550 fs/ext4/namei.c:2801 lookup_open fs/namei.c:3416 [inline] open_last_lookups fs/namei.c:3484 [inline] path_openat+0x13df/0x3170 fs/namei.c:3712 do_filp_open+0x234/0x490 fs/namei.c:3742 do_sys_openat2+0x13f/0x500 fs/open.c:1348 do_sys_open fs/open.c:1364 [inline] __do_sys_open fs/open.c:1372 [inline] __se_sys_open fs/open.c:1368 [inline] __x64_sys_open+0x225/0x270 fs/open.c:1368 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #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+0x166b/0x58e0 kernel/locking/lockdep.c:3832 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056 lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799 dquot_commit+0x5b/0x520 fs/quota/dquot.c:479 ext4_write_dquot+0x1f2/0x2c0 fs/ext4/super.c:6754 mark_dquot_dirty fs/quota/dquot.c:346 [inline] mark_all_dquot_dirty fs/quota/dquot.c:384 [inline] __dquot_alloc_space+0x54c/0xf50 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+0x111a/0x45f0 fs/ext4/mballoc.c:5571 ext4_ext_map_blocks+0x1973/0x7210 fs/ext4/extents.c:4286 ext4_map_blocks+0xa4c/0x1cf0 fs/ext4/inode.c:651 _ext4_get_block+0x238/0x6a0 fs/ext4/inode.c:807 ext4_block_write_begin+0x650/0x1400 fs/ext4/inode.c:1097 ext4_write_begin+0x626/0xee0 ext4_da_write_begin+0x42c/0x960 fs/ext4/inode.c:3057 generic_perform_write+0x300/0x5e0 mm/filemap.c:3926 ext4_buffered_write_iter+0x122/0x3a0 fs/ext4/file.c:289 ext4_file_write_iter+0x1d6/0x1930 do_iter_write+0x7b1/0xcb0 fs/read_write.c:860 iter_file_splice_write+0x843/0xfe0 fs/splice.c:778 do_splice_from fs/splice.c:856 [inline] direct_splice_actor+0xe7/0x1c0 fs/splice.c:1022 splice_direct_to_actor+0x4c4/0xbd0 fs/splice.c:977 do_splice_direct+0x283/0x3d0 fs/splice.c:1065 do_sendfile+0x620/0xff0 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd 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.3/9283: #0: ffff88802fa4e460 (sb_writers#4){.+.+}-{0:0}, at: do_sendfile+0x5fb/0xff0 fs/read_write.c:1253 #1: ffff888076d3f258 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff888076d3f258 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: ext4_buffered_write_iter+0xaf/0x3a0 fs/ext4/file.c:283 #2: ffff888076d3f0e0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x980/0x1cf0 fs/ext4/inode.c:644 #3: ffffffff8d0698c8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x40 include/linux/rcupdate.h:326 stack backtrace: CPU: 1 PID: 9283 Comm: syz-executor.3 Not tainted 6.3.0-syzkaller-00113-g1a0beef98b58 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2fe/0x3b0 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+0x166b/0x58e0 kernel/locking/lockdep.c:3832 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056 lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799 dquot_commit+0x5b/0x520 fs/quota/dquot.c:479 ext4_write_dquot+0x1f2/0x2c0 fs/ext4/super.c:6754 mark_dquot_dirty fs/quota/dquot.c:346 [inline] mark_all_dquot_dirty fs/quota/dquot.c:384 [inline] __dquot_alloc_space+0x54c/0xf50 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+0x111a/0x45f0 fs/ext4/mballoc.c:5571 ext4_ext_map_blocks+0x1973/0x7210 fs/ext4/extents.c:4286 ext4_map_blocks+0xa4c/0x1cf0 fs/ext4/inode.c:651 _ext4_get_block+0x238/0x6a0 fs/ext4/inode.c:807 ext4_block_write_begin+0x650/0x1400 fs/ext4/inode.c:1097 ext4_write_begin+0x626/0xee0 ext4_da_write_begin+0x42c/0x960 fs/ext4/inode.c:3057 generic_perform_write+0x300/0x5e0 mm/filemap.c:3926 ext4_buffered_write_iter+0x122/0x3a0 fs/ext4/file.c:289 ext4_file_write_iter+0x1d6/0x1930 do_iter_write+0x7b1/0xcb0 fs/read_write.c:860 iter_file_splice_write+0x843/0xfe0 fs/splice.c:778 do_splice_from fs/splice.c:856 [inline] direct_splice_actor+0xe7/0x1c0 fs/splice.c:1022 splice_direct_to_actor+0x4c4/0xbd0 fs/splice.c:977 do_splice_direct+0x283/0x3d0 fs/splice.c:1065 do_sendfile+0x620/0xff0 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7ffaf1c8c169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffaf2a92168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007ffaf1dabf80 RCX: 00007ffaf1c8c169 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005 RBP: 00007ffaf1ce7ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0001000000201005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff9982b17f R14: 00007ffaf2a92300 R15: 0000000000022000