loop1: detected capacity change from 0 to 2048 EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue. Quota mode: none. ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.24/4366 is trying to acquire lock: ffff8880603880c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ffff8880603880c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1908 but task is already holding lock: ffff888021380c58 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2d40 fs/ext4/inode.c:2691 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sbi->s_writepages_rwsem){.+.+}-{0:0}: percpu_down_read+0x46/0x1b0 include/linux/percpu-rwsem.h:51 ext4_writepages+0x213/0x2d40 fs/ext4/inode.c:2691 do_writepages+0x493/0x700 mm/page-writeback.c:2386 __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657 writeback_single_inode+0x3d2/0x8e0 fs/fs-writeback.c:1770 write_inode_now+0x23b/0x2c0 fs/fs-writeback.c:2817 iput_final fs/inode.c:1756 [inline] iput+0x599/0x880 fs/inode.c:1795 ext4_xattr_set_entry+0x1d76/0x3f70 fs/ext4/xattr.c:1827 ext4_xattr_block_set+0x4d7/0x2ce0 fs/ext4/xattr.c:1926 ext4_xattr_move_to_block fs/ext4/xattr.c:2620 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2695 [inline] ext4_expand_extra_isize_ea+0xebe/0x18e0 fs/ext4/xattr.c:2783 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5924 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5967 [inline] __ext4_mark_inode_dirty+0x444/0x6c0 fs/ext4/inode.c:6045 ext4_evict_inode+0xa55/0x1050 fs/ext4/inode.c:284 evict+0x4b6/0x8b0 fs/inode.c:647 ext4_orphan_cleanup+0xad8/0x1320 fs/ext4/orphan.c:472 ext4_fill_super+0x8c65/0x93f0 fs/ext4/super.c:5006 mount_bdev+0x28a/0x3c0 fs/super.c:1400 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x247/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (&ei->xattr_sem){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c66/0x7b50 kernel/locking/lockdep.c:5012 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 down_write+0x38/0x60 kernel/locking/rwsem.c:1551 ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1908 ext4_writepages+0x599/0x2d40 fs/ext4/inode.c:2737 do_writepages+0x493/0x700 mm/page-writeback.c:2386 filemap_fdatawrite_wbc+0x1eb/0x240 mm/filemap.c:400 __filemap_fdatawrite_range mm/filemap.c:433 [inline] __filemap_fdatawrite mm/filemap.c:439 [inline] filemap_flush+0xd4/0x130 mm/filemap.c:466 ext4_convert_inline_data+0x186/0x5b0 fs/ext4/inline.c:2084 ext4_page_mkwrite+0x1df/0x1250 fs/ext4/inode.c:6199 do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 wp_page_shared+0x163/0x6c0 mm/memory.c:3259 handle_pte_fault mm/memory.c:4668 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x1fbd/0x4440 mm/memory.c:4883 do_user_addr_fault+0x494/0xc90 arch/x86/mm/fault.c:1355 handle_page_fault arch/x86/mm/fault.c:1443 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 copy_user_enhanced_fast_string+0xe/0x40 arch/x86/lib/copy_user_64.S:205 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline] copyout lib/iov_iter.c:157 [inline] copy_page_to_iter_iovec lib/iov_iter.c:228 [inline] __copy_page_to_iter lib/iov_iter.c:861 [inline] copy_page_to_iter+0x4c9/0x930 lib/iov_iter.c:889 filemap_read+0x1e0a/0x2560 mm/filemap.c:2698 call_read_iter include/linux/fs.h:2167 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0x75e/0xd50 fs/read_write.c:485 ksys_read+0x153/0x260 fs/read_write.c:623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); lock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); *** DEADLOCK *** 5 locks held by syz.1.24/4366: #0: ffff888077227770 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2bf/0x370 fs/file.c:1056 #1: ffff88807dbc0f28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #1: ffff88807dbc0f28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2bb/0xc90 arch/x86/mm/fault.c:1296 #2: ffff888021382558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1811 [inline] #2: ffff888021382558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1910 [inline] #2: ffff888021382558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1a5/0x1250 fs/ext4/inode.c:6194 #3: ffff888060388590 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:842 [inline] #3: ffff888060388590 (mapping.invalidate_lock){++++}-{3:3}, at: ext4_page_mkwrite+0x1d2/0x1250 fs/ext4/inode.c:6197 #4: ffff888021380c58 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2d40 fs/ext4/inode.c:2691 stack backtrace: CPU: 0 PID: 4366 Comm: syz.1.24 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 check_noncircular+0x296/0x330 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 kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c66/0x7b50 kernel/locking/lockdep.c:5012 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 down_write+0x38/0x60 kernel/locking/rwsem.c:1551 ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1908 ext4_writepages+0x599/0x2d40 fs/ext4/inode.c:2737 do_writepages+0x493/0x700 mm/page-writeback.c:2386 filemap_fdatawrite_wbc+0x1eb/0x240 mm/filemap.c:400 __filemap_fdatawrite_range mm/filemap.c:433 [inline] __filemap_fdatawrite mm/filemap.c:439 [inline] filemap_flush+0xd4/0x130 mm/filemap.c:466 ext4_convert_inline_data+0x186/0x5b0 fs/ext4/inline.c:2084 ext4_page_mkwrite+0x1df/0x1250 fs/ext4/inode.c:6199 do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922 wp_page_shared+0x163/0x6c0 mm/memory.c:3259 handle_pte_fault mm/memory.c:4668 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x1fbd/0x4440 mm/memory.c:4883 do_user_addr_fault+0x494/0xc90 arch/x86/mm/fault.c:1355 handle_page_fault arch/x86/mm/fault.c:1443 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1496 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0010:copy_user_enhanced_fast_string+0xe/0x40 arch/x86/lib/copy_user_64.S:206 Code: 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 0f 01 cb 83 fa 40 0f 82 70 ff ff ff 89 d1 a4 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 90 90 90 89 d1 83 f8 RSP: 0018:ffffc90004d9f940 EFLAGS: 00050206 RAX: ffffffff83e64201 RBX: 0000000000001000 RCX: 0000000000001000 RDX: 0000000000001000 RSI: ffff88805b942000 RDI: 0000200000000400 RBP: ffff88805b942000 R08: ffff88805b942fff R09: 1ffff1100b7285ff R10: dffffc0000000000 R11: ffffed100b728600 R12: 0000000000001000 R13: 00000000000010ff R14: 00007ffffffff000 R15: 0000200000001400 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline] copyout lib/iov_iter.c:157 [inline] copy_page_to_iter_iovec lib/iov_iter.c:228 [inline] __copy_page_to_iter lib/iov_iter.c:861 [inline] copy_page_to_iter+0x4c9/0x930 lib/iov_iter.c:889 filemap_read+0x1e0a/0x2560 mm/filemap.c:2698 call_read_iter include/linux/fs.h:2167 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0x75e/0xd50 fs/read_write.c:485 ksys_read+0x153/0x260 fs/read_write.c:623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f6f1a863e99 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6f18abc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f6f1aaebfa0 RCX: 00007f6f1a863e99 RDX: 00000000fffffeb1 RSI: 0000200000000400 RDI: 0000000000000006 RBP: 00007f6f1a8f9eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6f1aaec038 R14: 00007f6f1aaebfa0 R15: 00007ffc29bbb6c8 EXT4-fs error (device loop1): ext4_mb_generate_buddy:1176: group 0, block bitmap and bg descriptor inconsistent: 25 vs 281 free clusters EXT4-fs (loop1): Delayed block allocation failed for inode 15 at logical offset 31 with max blocks 33 with error 28 EXT4-fs (loop1): This should not happen!! Data will be lost EXT4-fs (loop1): Total free blocks count 0 EXT4-fs (loop1): Free/Dirty block details EXT4-fs (loop1): free_blocks=4096 EXT4-fs (loop1): dirty_blocks=64 EXT4-fs (loop1): Block reservation details EXT4-fs (loop1): i_reserved_data_blocks=4 ---------------- Code disassembly (best guess): 0: 89 d1 mov %edx,%ecx 2: c1 e9 03 shr $0x3,%ecx 5: 83 e2 07 and $0x7,%edx 8: f3 48 a5 rep movsq %ds:(%rsi),%es:(%rdi) b: 89 d1 mov %edx,%ecx d: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) f: 31 c0 xor %eax,%eax 11: 0f 01 ca clac 14: c3 ret 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: 90 nop 1c: 0f 01 cb stac 1f: 83 fa 40 cmp $0x40,%edx 22: 0f 82 70 ff ff ff jb 0xffffff98 28: 89 d1 mov %edx,%ecx * 2a: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction 2c: 31 c0 xor %eax,%eax 2e: 0f 01 ca clac 31: c3 ret 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 89 d1 mov %edx,%ecx 3e: 83 .byte 0x83 3f: f8 clc