loop4: detected capacity change from 0 to 512
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G L
------------------------------------------------------
syz.4.4262/21618 is trying to acquire lock:
ffff88802a062b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x27a/0x600 mm/page-writeback.c:2598
but task is already holding lock:
ffff888098ad8a68 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
ffff888098ad8a68 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6389 [inline]
ffff888098ad8a68 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x4ba/0x840 fs/ext4/inode.c:6470
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&ei->xattr_sem){++++}-{4:4}:
down_write+0x92/0x200 kernel/locking/rwsem.c:1590
ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline]
ext4_destroy_inline_data+0x2d/0xe0 fs/ext4/inline.c:1797
ext4_do_writepages+0x1154/0x3c80 fs/ext4/inode.c:2811
ext4_writepages+0x37a/0x7d0 fs/ext4/inode.c:3026
do_writepages+0x27a/0x600 mm/page-writeback.c:2598
filemap_writeback+0x225/0x2d0 mm/filemap.c:387
filemap_fdatawrite_range mm/filemap.c:412 [inline]
file_write_and_wait_range+0xcd/0x140 mm/filemap.c:786
generic_buffers_fsync_noflush+0x76/0x350 fs/buffer.c:609
ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
ext4_sync_file+0x83f/0xeb0 fs/ext4/fsync.c:147
vfs_fsync_range+0x142/0x230 fs/sync.c:188
generic_write_sync include/linux/fs.h:2616 [inline]
ext4_buffered_write_iter+0x2e0/0x440 fs/ext4/file.c:305
ext4_file_write_iter+0xa5b/0x1d00 fs/ext4/file.c:723
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x7d3/0x11d0 fs/read_write.c:686
ksys_pwrite64 fs/read_write.c:793 [inline]
__do_sys_pwrite64 fs/read_write.c:801 [inline]
__se_sys_pwrite64 fs/read_write.c:798 [inline]
__x64_sys_pwrite64+0x1eb/0x250 fs/read_write.c:798
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&sbi->s_writepages_rwsem){++++}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain kernel/locking/lockdep.c:3908 [inline]
__lock_acquire+0x1669/0x2890 kernel/locking/lockdep.c:5237
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825
percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
ext4_writepages_down_read fs/ext4/ext4.h:1820 [inline]
ext4_writepages+0x224/0x7d0 fs/ext4/inode.c:3025
do_writepages+0x27a/0x600 mm/page-writeback.c:2598
__writeback_single_inode+0x168/0x14a0 fs/fs-writeback.c:1737
writeback_single_inode+0x425/0x10f0 fs/fs-writeback.c:1858
write_inode_now+0x170/0x1e0 fs/fs-writeback.c:2924
iput_final fs/inode.c:1941 [inline]
iput.part.0+0x815/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
ext4_xattr_block_set+0x67c/0x3640 fs/ext4/xattr.c:2203
ext4_xattr_move_to_block fs/ext4/xattr.c:2668 [inline]
ext4_xattr_make_inode_space fs/ext4/xattr.c:2743 [inline]
ext4_expand_extra_isize_ea+0x1442/0x1ab0 fs/ext4/xattr.c:2831
__ext4_expand_extra_isize+0x346/0x480 fs/ext4/inode.c:6349
ext4_try_to_expand_extra_isize fs/ext4/inode.c:6392 [inline]
__ext4_mark_inode_dirty+0x544/0x840 fs/ext4/inode.c:6470
ext4_evict_inode+0x713/0x1730 fs/ext4/inode.c:253
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
ext4_orphan_cleanup+0x731/0x11e0 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5658 [inline]
ext4_fill_super+0x7ec1/0xb570 fs/ext4/super.c:5777
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1691
vfs_get_tree+0x8e/0x330 fs/super.c:1751
fc_mount fs/namespace.c:1199 [inline]
do_new_mount_fc fs/namespace.c:3636 [inline]
do_new_mount fs/namespace.c:3712 [inline]
path_mount+0x7bf/0x23a0 fs/namespace.c:4022
do_mount fs/namespace.c:4035 [inline]
__do_sys_mount fs/namespace.c:4224 [inline]
__se_sys_mount fs/namespace.c:4201 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4201
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
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);
rlock(&sbi->s_writepages_rwsem);
*** DEADLOCK ***
3 locks held by syz.4.4262/21618:
#0: ffff88803b2680e0 (&type->s_umount_key#27/1){+.+.}-{4:4}, at: alloc_super+0x244/0xd00 fs/super.c:344
#1: ffff88803b268610 (sb_internal){++++}-{0:0}, at: evict+0x3c2/0xad0 fs/inode.c:837
#2: ffff888098ad8a68 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
#2: ffff888098ad8a68 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6389 [inline]
#2: ffff888098ad8a68 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x4ba/0x840 fs/ext4/inode.c:6470
stack backtrace:
CPU: 1 UID: 0 PID: 21618 Comm: syz.4.4262 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_circular_bug+0x275/0x340 kernel/locking/lockdep.c:2043
check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2175
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain kernel/locking/lockdep.c:3908 [inline]
__lock_acquire+0x1669/0x2890 kernel/locking/lockdep.c:5237
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825
percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
ext4_writepages_down_read fs/ext4/ext4.h:1820 [inline]
ext4_writepages+0x224/0x7d0 fs/ext4/inode.c:3025
do_writepages+0x27a/0x600 mm/page-writeback.c:2598
__writeback_single_inode+0x168/0x14a0 fs/fs-writeback.c:1737
writeback_single_inode+0x425/0x10f0 fs/fs-writeback.c:1858
write_inode_now+0x170/0x1e0 fs/fs-writeback.c:2924
iput_final fs/inode.c:1941 [inline]
iput.part.0+0x815/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
ext4_xattr_block_set+0x67c/0x3640 fs/ext4/xattr.c:2203
ext4_xattr_move_to_block fs/ext4/xattr.c:2668 [inline]
ext4_xattr_make_inode_space fs/ext4/xattr.c:2743 [inline]
ext4_expand_extra_isize_ea+0x1442/0x1ab0 fs/ext4/xattr.c:2831
__ext4_expand_extra_isize+0x346/0x480 fs/ext4/inode.c:6349
ext4_try_to_expand_extra_isize fs/ext4/inode.c:6392 [inline]
__ext4_mark_inode_dirty+0x544/0x840 fs/ext4/inode.c:6470
ext4_evict_inode+0x713/0x1730 fs/ext4/inode.c:253
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
ext4_orphan_cleanup+0x731/0x11e0 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5658 [inline]
ext4_fill_super+0x7ec1/0xb570 fs/ext4/super.c:5777
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1691
vfs_get_tree+0x8e/0x330 fs/super.c:1751
fc_mount fs/namespace.c:1199 [inline]
do_new_mount_fc fs/namespace.c:3636 [inline]
do_new_mount fs/namespace.c:3712 [inline]
path_mount+0x7bf/0x23a0 fs/namespace.c:4022
do_mount fs/namespace.c:4035 [inline]
__do_sys_mount fs/namespace.c:4224 [inline]
__se_sys_mount fs/namespace.c:4201 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4201
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4571990eea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f45728abe68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f45728abef0 RCX: 00007f4571990eea
RDX: 0000200000000180 RSI: 00002000000001c0 RDI: 00007f45728abeb0
RBP: 0000200000000180 R08: 00007f45728abef0 R09: 0000000000800718
R10: 0000000000800718 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f45728abeb0 R14: 000000000000046f R15: 0000200000000200
------------[ cut here ]------------
EA inode 11 i_nlink=2
WARNING: fs/ext4/xattr.c:1056 at 0x0, CPU#0: syz.4.4262/21618
Modules linked in:
CPU: 0 UID: 0 PID: 21618 Comm: syz.4.4262 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:ext4_xattr_inode_update_ref+0x4be/0x5b0 fs/ext4/xattr.c:1056
Code: 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 f1 00 00 00 48 8d 3d 69 4e fa 0d 48 8b 73 40 44 89 e2 <67> 48 0f b9 3a e9 06 ff ff ff e8 13 0e 2b ff 48 8d 7b 40 48 b8 00
RSP: 0018:ffffc9000e1bf178 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff888098ad9f78 RCX: ffffc90013ed4000
RDX: 0000000000000002 RSI: 000000000000000b RDI: ffffffff908e2450
RBP: ffffc9000e1bf240 R08: 0000000000000005 R09: 0000000000000001
R10: 0000000000000002 R11: 0000000000000001 R12: 0000000000000002
R13: ffffffffffffffff R14: 1ffff92001c37e32 R15: ffff888098ada168
FS: 00007f45728ac6c0(0000) GS:ffff888124908000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3bccb156c0 CR3: 000000003a7d0000 CR4: 0000000000350ef0
Call Trace:
ext4_xattr_inode_dec_ref fs/ext4/xattr.c:1081 [inline]
ext4_xattr_set_entry+0x158f/0x1f00 fs/ext4/xattr.c:1723
ext4_xattr_ibody_set+0x3d6/0x5d0 fs/ext4/xattr.c:2272
ext4_xattr_move_to_block fs/ext4/xattr.c:2675 [inline]
ext4_xattr_make_inode_space fs/ext4/xattr.c:2743 [inline]
ext4_expand_extra_isize_ea+0x148c/0x1ab0 fs/ext4/xattr.c:2831
__ext4_expand_extra_isize+0x346/0x480 fs/ext4/inode.c:6349
ext4_try_to_expand_extra_isize fs/ext4/inode.c:6392 [inline]
__ext4_mark_inode_dirty+0x544/0x840 fs/ext4/inode.c:6470
ext4_evict_inode+0x713/0x1730 fs/ext4/inode.c:253
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
ext4_orphan_cleanup+0x731/0x11e0 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5658 [inline]
ext4_fill_super+0x7ec1/0xb570 fs/ext4/super.c:5777
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1691
vfs_get_tree+0x8e/0x330 fs/super.c:1751
fc_mount fs/namespace.c:1199 [inline]
do_new_mount_fc fs/namespace.c:3636 [inline]
do_new_mount fs/namespace.c:3712 [inline]
path_mount+0x7bf/0x23a0 fs/namespace.c:4022
do_mount fs/namespace.c:4035 [inline]
__do_sys_mount fs/namespace.c:4224 [inline]
__se_sys_mount fs/namespace.c:4201 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4201
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4571990eea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f45728abe68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f45728abef0 RCX: 00007f4571990eea
RDX: 0000200000000180 RSI: 00002000000001c0 RDI: 00007f45728abeb0
RBP: 0000200000000180 R08: 00007f45728abef0 R09: 0000000000800718
R10: 0000000000800718 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f45728abeb0 R14: 000000000000046f R15: 0000200000000200
----------------
Code disassembly (best guess):
0: 40 rex
1: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
8: fc ff df
b: 48 89 fa mov %rdi,%rdx
e: 48 c1 ea 03 shr $0x3,%rdx
12: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
16: 0f 85 f1 00 00 00 jne 0x10d
1c: 48 8d 3d 69 4e fa 0d lea 0xdfa4e69(%rip),%rdi # 0xdfa4e8c
23: 48 8b 73 40 mov 0x40(%rbx),%rsi
27: 44 89 e2 mov %r12d,%edx
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: e9 06 ff ff ff jmp 0xffffff3a
34: e8 13 0e 2b ff call 0xff2b0e4c
39: 48 8d 7b 40 lea 0x40(%rbx),%rdi
3d: 48 rex.W
3e: b8 .byte 0xb8