====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.1789/12745 is trying to acquire lock: ffff8880239a6bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x20f/0x2df0 fs/ext4/inode.c:2689 but task is already holding lock: ffff88805ea25088 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:165 [inline] ffff88805ea25088 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:5945 [inline] ffff88805ea25088 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x3e8/0x700 fs/ext4/inode.c:6026 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&ei->xattr_sem){++++}-{3:3}: 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:1900 ext4_writepages+0x670/0x2df0 fs/ext4/inode.c:2735 do_writepages+0x476/0x6e0 mm/page-writeback.c:2386 filemap_fdatawrite_wbc+0x1eb/0x240 mm/filemap.c:400 __filemap_fdatawrite_range mm/filemap.c:433 [inline] file_write_and_wait_range+0x14d/0x220 mm/filemap.c:810 ext4_sync_file+0x1ff/0xae0 fs/ext4/fsync.c:151 generic_write_sync include/linux/fs.h:2990 [inline] ext4_buffered_write_iter+0x338/0x3b0 fs/ext4/file.c:275 ext4_file_write_iter+0x74d/0x1700 fs/ext4/file.c:-1 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x745/0xd60 fs/read_write.c:594 ksys_pwrite64 fs/read_write.c:701 [inline] __do_sys_pwrite64 fs/read_write.c:711 [inline] __se_sys_pwrite64 fs/read_write.c:708 [inline] __x64_sys_pwrite64+0x19a/0x220 fs/read_write.c:708 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 (&sbi->s_writepages_rwsem){.+.+}-{0:0}: 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+0x2c42/0x7d10 kernel/locking/lockdep.c:5012 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 percpu_down_read+0x46/0x1b0 include/linux/percpu-rwsem.h:51 ext4_writepages+0x20f/0x2df0 fs/ext4/inode.c:2689 do_writepages+0x476/0x6e0 mm/page-writeback.c:2386 __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657 writeback_single_inode+0x3cb/0x8e0 fs/fs-writeback.c:1770 write_inode_now+0x23b/0x2c0 fs/fs-writeback.c:2811 iput_final fs/inode.c:1756 [inline] iput+0x5ab/0x8a0 fs/inode.c:1795 ext4_xattr_set_entry+0x34f4/0x3ea0 fs/ext4/xattr.c:1824 ext4_xattr_block_set+0x4fd/0x2d20 fs/ext4/xattr.c:1923 ext4_xattr_move_to_block fs/ext4/xattr.c:2617 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2692 [inline] ext4_expand_extra_isize_ea+0xf3f/0x19b0 fs/ext4/xattr.c:2780 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5905 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5948 [inline] __ext4_mark_inode_dirty+0x469/0x700 fs/ext4/inode.c:6026 ext4_evict_inode+0xa8d/0x1090 fs/ext4/inode.c:282 evict+0x4c9/0x8d0 fs/inode.c:647 ext4_orphan_cleanup+0xad2/0x1320 fs/ext4/orphan.c:472 ext4_fill_super+0x8e25/0x95a0 fs/ext4/super.c:5000 mount_bdev+0x287/0x3c0 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+0x24a/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 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->xattr_sem); lock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); lock(&sbi->s_writepages_rwsem); *** DEADLOCK *** 3 locks held by syz.2.1789/12745: #0: ffff8880685440e0 (&type->s_umount_key#28/1){+.+.}-{3:3}, at: alloc_super+0x201/0x950 fs/super.c:229 #1: ffff888068544650 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1811 [inline] #1: ffff888068544650 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs.h:1928 [inline] #1: ffff888068544650 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x44a/0x1090 fs/ext4/inode.c:243 #2: ffff88805ea25088 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:165 [inline] #2: ffff88805ea25088 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:5945 [inline] #2: ffff88805ea25088 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x3e8/0x700 fs/ext4/inode.c:6026 stack backtrace: CPU: 1 PID: 12745 Comm: syz.2.1789 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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+0x2c42/0x7d10 kernel/locking/lockdep.c:5012 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 percpu_down_read+0x46/0x1b0 include/linux/percpu-rwsem.h:51 ext4_writepages+0x20f/0x2df0 fs/ext4/inode.c:2689 do_writepages+0x476/0x6e0 mm/page-writeback.c:2386 __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657 writeback_single_inode+0x3cb/0x8e0 fs/fs-writeback.c:1770 write_inode_now+0x23b/0x2c0 fs/fs-writeback.c:2811 iput_final fs/inode.c:1756 [inline] iput+0x5ab/0x8a0 fs/inode.c:1795 ext4_xattr_set_entry+0x34f4/0x3ea0 fs/ext4/xattr.c:1824 ext4_xattr_block_set+0x4fd/0x2d20 fs/ext4/xattr.c:1923 ext4_xattr_move_to_block fs/ext4/xattr.c:2617 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2692 [inline] ext4_expand_extra_isize_ea+0xf3f/0x19b0 fs/ext4/xattr.c:2780 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5905 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5948 [inline] __ext4_mark_inode_dirty+0x469/0x700 fs/ext4/inode.c:6026 ext4_evict_inode+0xa8d/0x1090 fs/ext4/inode.c:282 evict+0x4c9/0x8d0 fs/inode.c:647 ext4_orphan_cleanup+0xad2/0x1320 fs/ext4/orphan.c:472 ext4_fill_super+0x8e25/0x95a0 fs/ext4/super.c:5000 mount_bdev+0x287/0x3c0 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+0x24a/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 RIP: 0033:0x7fb4821e1f4a Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007fb48041ae58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb48041aee0 RCX: 00007fb4821e1f4a RDX: 0000200000000180 RSI: 00002000000001c0 RDI: 00007fb48041aea0 RBP: 0000200000000180 R08: 00007fb48041aee0 R09: 0000000000800700 R10: 0000000000800700 R11: 0000000000000246 R12: 00002000000001c0 R13: 00007fb48041aea0 R14: 000000000000046f R15: 0000200000000400 ------------[ cut here ]------------ EA inode 11 i_nlink=2 WARNING: CPU: 1 PID: 12745 at fs/ext4/xattr.c:1005 ext4_xattr_inode_update_ref+0x4bd/0x510 fs/ext4/xattr.c:1003 Modules linked in: CPU: 1 PID: 12745 Comm: syz.2.1789 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:ext4_xattr_inode_update_ref+0x4bd/0x510 fs/ext4/xattr.c:1003 Code: 7c 24 40 4c 89 f8 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 14 e8 a1 ff 49 8b 37 48 c7 c7 00 9b 3d 8a 89 da e8 a3 bd 94 07 <0f> 0b 4c 8b 64 24 08 4c 8b 7c 24 10 e9 a9 fe ff ff e8 ed ac 9f 07 RSP: 0018:ffffc900031ff160 EFLAGS: 00010246 RAX: 845bc95b588eff00 RBX: 0000000000000002 RCX: 0000000000080000 RDX: ffffc90013356000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc900031ff250 R08: ffffc900031fec87 R09: 1ffff9200063fd90 R10: dffffc0000000000 R11: fffff5200063fd91 R12: ffff88805ea26650 R13: 1ffff1100bd44d09 R14: dffffc0000000000 R15: ffff88805ea26690 FS: 00007fb48041b6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055da6e165950 CR3: 0000000079aa4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000009 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: ext4_xattr_inode_dec_ref fs/ext4/xattr.c:1028 [inline] ext4_xattr_set_entry+0xed9/0x3ea0 fs/ext4/xattr.c:1684 ext4_xattr_ibody_set+0x112/0x330 fs/ext4/xattr.c:2237 ext4_xattr_move_to_block fs/ext4/xattr.c:2624 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2692 [inline] ext4_expand_extra_isize_ea+0x10d3/0x19b0 fs/ext4/xattr.c:2780 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5905 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5948 [inline] __ext4_mark_inode_dirty+0x469/0x700 fs/ext4/inode.c:6026 ext4_evict_inode+0xa8d/0x1090 fs/ext4/inode.c:282 evict+0x4c9/0x8d0 fs/inode.c:647 ext4_orphan_cleanup+0xad2/0x1320 fs/ext4/orphan.c:472 ext4_fill_super+0x8e25/0x95a0 fs/ext4/super.c:5000 mount_bdev+0x287/0x3c0 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+0x24a/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 RIP: 0033:0x7fb4821e1f4a Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007fb48041ae58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb48041aee0 RCX: 00007fb4821e1f4a RDX: 0000200000000180 RSI: 00002000000001c0 RDI: 00007fb48041aea0 RBP: 0000200000000180 R08: 00007fb48041aee0 R09: 0000000000800700 R10: 0000000000800700 R11: 0000000000000246 R12: 00002000000001c0 R13: 00007fb48041aea0 R14: 000000000000046f R15: 0000200000000400