loop2: detected capacity change from 0 to 4096 EXT4-fs (loop2): mounted filesystem without journal. Quota mode: writeback. fs-verity: sha256 using implementation "sha256-avx2" ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.2626/15525 is trying to acquire lock: ffff8880571b5e68 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 but task is already holding lock: ffff888072fa9698 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x903/0x1b60 fs/ext4/inode.c:672 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+0x42/0x2d0 kernel/locking/rwsem.c:1520 ext4_map_blocks+0x316/0x1b60 fs/ext4/inode.c:604 ext4_getblk+0x1ab/0x6d0 fs/ext4/inode.c:890 ext4_bread+0x26/0x170 fs/ext4/inode.c:946 ext4_quota_read+0x180/0x380 fs/ext4/super.c:7150 read_blk fs/quota/quota_tree.c:61 [inline] find_tree_dqentry+0x1cd/0xf30 fs/quota/quota_tree.c:671 find_tree_dqentry+0x6b0/0xf30 fs/quota/quota_tree.c:698 find_tree_dqentry+0x6b0/0xf30 fs/quota/quota_tree.c:698 find_tree_dqentry+0x6b0/0xf30 fs/quota/quota_tree.c:698 find_dqentry fs/quota/quota_tree.c:716 [inline] qtree_read_dquot+0x558/0x7f0 fs/quota/quota_tree.c:736 v2_read_dquot+0xc0/0x110 fs/quota/quota_v2.c:336 dquot_acquire+0x152/0x520 fs/quota/dquot.c:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6805 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x328/0xcb0 fs/quota/dquot.c:1517 ext4_process_orphan+0x54/0x300 fs/ext4/orphan.c:325 ext4_orphan_cleanup+0xbd3/0x1400 fs/ext4/orphan.c:470 __ext4_fill_super fs/ext4/super.c:5530 [inline] ext4_fill_super+0x7bdf/0x8150 fs/ext4/super.c:5661 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #1 (&s->s_dquot.dqio_sem){++++}-{3:3}: down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520 v2_read_dquot+0x4a/0x110 fs/quota/quota_v2.c:335 dquot_acquire+0x152/0x520 fs/quota/dquot.c:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6805 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x328/0xcb0 fs/quota/dquot.c:1517 ext4_process_orphan+0x54/0x300 fs/ext4/orphan.c:325 ext4_orphan_cleanup+0xbd3/0x1400 fs/ext4/orphan.c:470 __ext4_fill_super fs/ext4/super.c:5530 [inline] ext4_fill_super+0x7bdf/0x8150 fs/ext4/super.c:5661 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&dquot->dq_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6785 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_alloc_space+0x5fc/0xe60 fs/quota/dquot.c:1752 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+0xf74/0x4720 fs/ext4/mballoc.c:5722 ext4_ext_map_blocks+0x18de/0x66d0 fs/ext4/extents.c:4340 ext4_map_blocks+0x9d1/0x1b60 fs/ext4/inode.c:679 _ext4_get_block+0x1d7/0x4e0 fs/ext4/inode.c:822 ext4_get_block_unwritten+0x2a/0x100 fs/ext4/inode.c:855 ext4_block_write_begin+0x637/0x12f0 fs/ext4/inode.c:1124 ext4_write_begin+0x624/0xf50 fs/ext4/ext4_jbd2.h:-1 ext4_da_write_begin+0x304/0x950 fs/ext4/inode.c:3000 pagecache_write+0x1fa/0x350 fs/ext4/verity.c:85 build_merkle_tree_level fs/verity/enable.c:121 [inline] build_merkle_tree fs/verity/enable.c:182 [inline] enable_verity+0x10dc/0x1ed0 fs/verity/enable.c:268 fsverity_ioctl_enable+0x3ab/0x450 fs/verity/enable.c:392 __ext4_ioctl fs/ext4/ioctl.c:1580 [inline] ext4_ioctl+0x1869/0x3dd0 fs/ext4/ioctl.c:1614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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 *** 3 locks held by syz.2.2626/15525: #0: ffff88802cc64460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:446 #1: ffff888072fa9698 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x903/0x1b60 fs/ext4/inode.c:672 #2: ffffffff8cc71e08 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #2: ffffffff8cc71e08 (dquot_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline] #2: ffffffff8cc71e08 (dquot_srcu){....}-{0:0}, at: __dquot_alloc_space+0x173/0xe60 fs/quota/dquot.c:1716 stack backtrace: CPU: 1 PID: 15525 Comm: syz.2.2626 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6785 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_alloc_space+0x5fc/0xe60 fs/quota/dquot.c:1752 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+0xf74/0x4720 fs/ext4/mballoc.c:5722 ext4_ext_map_blocks+0x18de/0x66d0 fs/ext4/extents.c:4340 ext4_map_blocks+0x9d1/0x1b60 fs/ext4/inode.c:679 _ext4_get_block+0x1d7/0x4e0 fs/ext4/inode.c:822 ext4_get_block_unwritten+0x2a/0x100 fs/ext4/inode.c:855 ext4_block_write_begin+0x637/0x12f0 fs/ext4/inode.c:1124 ext4_write_begin+0x624/0xf50 fs/ext4/ext4_jbd2.h:-1 ext4_da_write_begin+0x304/0x950 fs/ext4/inode.c:3000 pagecache_write+0x1fa/0x350 fs/ext4/verity.c:85 build_merkle_tree_level fs/verity/enable.c:121 [inline] build_merkle_tree fs/verity/enable.c:182 [inline] enable_verity+0x10dc/0x1ed0 fs/verity/enable.c:268 fsverity_ioctl_enable+0x3ab/0x450 fs/verity/enable.c:392 __ext4_ioctl fs/ext4/ioctl.c:1580 [inline] ext4_ioctl+0x1869/0x3dd0 fs/ext4/ioctl.c:1614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fbd77b8f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbd789f5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fbd77de5fa0 RCX: 00007fbd77b8f749 RDX: 0000200000000200 RSI: 0000000040806685 RDI: 0000000000000007 RBP: 00007fbd77c13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fbd77de6038 R14: 00007fbd77de5fa0 R15: 00007fffdf9045d8 fs-verity (loop2, inode 16): fs-verity keyring is empty, rejecting signed file!