======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.6.399/8788 is trying to acquire lock:
ffff88801a18ccd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
ffff88801a18ccd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
ffff88801a18ccd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3041
but task is already holding lock:
ffff8880334bdf38 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
ffff8880334bdf38 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6474 [inline]
ffff8880334bdf38 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x3db/0x710 fs/ext4/inode.c:6555
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&ei->xattr_sem){++++}-{4:4}:
down_write+0x3a/0x50 kernel/locking/rwsem.c:1625
ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline]
ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1805
ext4_do_writepages+0x521/0x4670 fs/ext4/inode.c:2827
ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3042
do_writepages+0x32e/0x550 mm/page-writeback.c:2575
filemap_writeback mm/filemap.c:388 [inline]
filemap_flush_range mm/filemap.c:437 [inline]
filemap_flush+0x1e4/0x2f0 mm/filemap.c:452
ext4_convert_inline_data+0x18e/0x600 fs/ext4/inline.c:1972
ext4_page_mkwrite+0x24b/0x1150 fs/ext4/inode.c:6757
do_page_mkwrite+0x150/0x310 mm/memory.c:3668
do_shared_fault mm/memory.c:5969 [inline]
do_fault mm/memory.c:6031 [inline]
do_pte_missing+0x736/0x2950 mm/memory.c:4550
handle_pte_fault mm/memory.c:6411 [inline]
__handle_mm_fault mm/memory.c:6549 [inline]
handle_mm_fault+0xd0a/0x13c0 mm/memory.c:6718
do_user_addr_fault+0x75b/0x1340 arch/x86/mm/fault.c:1385
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
stac arch/x86/include/asm/smap.h:-1 [inline]
filldir+0x299/0x650 fs/readdir.c:286
dir_emit include/linux/fs.h:3578 [inline]
ext4_readdir+0x1877/0x41b0 fs/ext4/dir.c:277
iterate_dir+0x3a5/0x580 fs/readdir.c:110
__do_sys_getdents fs/readdir.c:319 [inline]
__se_sys_getdents+0xf1/0x270 fs/readdir.c:304
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
percpu_down_read_internal+0x48/0x1d0 include/linux/percpu-rwsem.h:53
percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3041
do_writepages+0x32e/0x550 mm/page-writeback.c:2575
__writeback_single_inode+0x133/0x10e0 fs/fs-writeback.c:1764
writeback_single_inode+0x488/0xd60 fs/fs-writeback.c:1883
write_inode_now+0x1c2/0x290 fs/fs-writeback.c:2974
iput_final fs/inode.c:1950 [inline]
iput+0x8c1/0xe80 fs/inode.c:2009
ext4_xattr_block_set+0x2359/0x2ad0 fs/ext4/xattr.c:2153
ext4_xattr_move_to_block fs/ext4/xattr.c:2671 [inline]
ext4_xattr_make_inode_space fs/ext4/xattr.c:2746 [inline]
ext4_expand_extra_isize_ea+0x12cf/0x1ea0 fs/ext4/xattr.c:2834
__ext4_expand_extra_isize+0x30d/0x400 fs/ext4/inode.c:6434
ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
__ext4_mark_inode_dirty+0x45c/0x710 fs/ext4/inode.c:6555
ext4_evict_inode+0x986/0x10e0 fs/ext4/inode.c:267
evict+0x61e/0xb10 fs/inode.c:841
ext4_orphan_cleanup+0xc38/0x1470 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5701 [inline]
ext4_fill_super+0x59bb/0x62d0 fs/ext4/super.c:5824
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3834
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/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.6.399/8788:
#0: ffff888032c3c0d0 (&type->s_umount_key#28/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
#1: ffff888032c3c770 (sb_internal){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
#1: ffff888032c3c770 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline]
#1: ffff888032c3c770 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs/super.h:177 [inline]
#1: ffff888032c3c770 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x426/0x10e0 fs/ext4/inode.c:228
#2: ffff8880334bdf38 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:164 [inline]
#2: ffff8880334bdf38 (&ei->xattr_sem){++++}-{4:4}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6474 [inline]
#2: ffff8880334bdf38 (&ei->xattr_sem){++++}-{4:4}, at: __ext4_mark_inode_dirty+0x3db/0x710 fs/ext4/inode.c:6555
stack backtrace:
CPU: 0 UID: 0 PID: 8788 Comm: syz.6.399 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043
check_noncircular+0x12e/0x150 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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
percpu_down_read_internal+0x48/0x1d0 include/linux/percpu-rwsem.h:53
percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
ext4_writepages_down_read fs/ext4/ext4.h:1811 [inline]
ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3041
do_writepages+0x32e/0x550 mm/page-writeback.c:2575
__writeback_single_inode+0x133/0x10e0 fs/fs-writeback.c:1764
writeback_single_inode+0x488/0xd60 fs/fs-writeback.c:1883
write_inode_now+0x1c2/0x290 fs/fs-writeback.c:2974
iput_final fs/inode.c:1950 [inline]
iput+0x8c1/0xe80 fs/inode.c:2009
ext4_xattr_block_set+0x2359/0x2ad0 fs/ext4/xattr.c:2153
ext4_xattr_move_to_block fs/ext4/xattr.c:2671 [inline]
ext4_xattr_make_inode_space fs/ext4/xattr.c:2746 [inline]
ext4_expand_extra_isize_ea+0x12cf/0x1ea0 fs/ext4/xattr.c:2834
__ext4_expand_extra_isize+0x30d/0x400 fs/ext4/inode.c:6434
ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
__ext4_mark_inode_dirty+0x45c/0x710 fs/ext4/inode.c:6555
ext4_evict_inode+0x986/0x10e0 fs/ext4/inode.c:267
evict+0x61e/0xb10 fs/inode.c:841
ext4_orphan_cleanup+0xc38/0x1470 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5701 [inline]
ext4_fill_super+0x59bb/0x62d0 fs/ext4/super.c:5824
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3834
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6c6f94e04a
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:00007f6c6db9de58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f6c6db9dee0 RCX: 00007f6c6f94e04a
RDX: 0000200000000180 RSI: 0000200000000000 RDI: 00007f6c6db9dea0
RBP: 0000200000000180 R08: 00007f6c6db9dee0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000000
R13: 00007f6c6db9dea0 R14: 000000000000047a R15: 0000200000000080
------------[ cut here ]------------
EA inode 11 i_nlink=0
WARNING: fs/ext4/xattr.c:1059 at ext4_xattr_inode_update_ref+0x4c9/0x5a0 fs/ext4/xattr.c:1057, CPU#0: syz.6.399/8788
Modules linked in:
CPU: 0 UID: 0 PID: 8788 Comm: syz.6.399 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:ext4_xattr_inode_update_ref+0x511/0x5a0 fs/ext4/xattr.c:1057
Code: 74 08 4c 89 ef e8 cf 31 9b ff 4d 8b 6d 00 48 b8 00 00 00 00 00 fc ff df 41 0f b6 04 06 84 c0 75 77 41 8b 17 4c 89 e7 4c 89 ee <67> 48 0f b9 3a 4c 8b 6c 24 28 e9 59 fe ff ff e8 db fa 8b 08 44 89
RSP: 0018:ffffc900054a7100 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 000000000000000b RDI: ffffffff8f8f2970
RBP: ffffc900054a7200 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100b9dd7fc R12: ffffffff8f8f2970
R13: 000000000000000b R14: 1ffff1100b9dd7c0 R15: ffff88805ceebe00
FS: 00007f6c6db9e6c0(0000) GS:ffff88812617a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000017000 CR3: 000000006f4b6000 CR4: 00000000003526f0
Call Trace:
ext4_xattr_inode_dec_ref fs/ext4/xattr.c:1082 [inline]
ext4_xattr_set_entry+0xabb/0x1e20 fs/ext4/xattr.c:1726
ext4_xattr_ibody_set+0x254/0x6a0 fs/ext4/xattr.c:2275
ext4_xattr_move_to_block fs/ext4/xattr.c:2678 [inline]
ext4_xattr_make_inode_space fs/ext4/xattr.c:2746 [inline]
ext4_expand_extra_isize_ea+0x13a2/0x1ea0 fs/ext4/xattr.c:2834
__ext4_expand_extra_isize+0x30d/0x400 fs/ext4/inode.c:6434
ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
__ext4_mark_inode_dirty+0x45c/0x710 fs/ext4/inode.c:6555
ext4_evict_inode+0x986/0x10e0 fs/ext4/inode.c:267
evict+0x61e/0xb10 fs/inode.c:841
ext4_orphan_cleanup+0xc38/0x1470 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5701 [inline]
ext4_fill_super+0x59bb/0x62d0 fs/ext4/super.c:5824
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3834
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6c6f94e04a
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:00007f6c6db9de58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f6c6db9dee0 RCX: 00007f6c6f94e04a
RDX: 0000200000000180 RSI: 0000200000000000 RDI: 00007f6c6db9dea0
RBP: 0000200000000180 R08: 00007f6c6db9dee0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000000
R13: 00007f6c6db9dea0 R14: 000000000000047a R15: 0000200000000080
----------------
Code disassembly (best guess):
0: 74 08 je 0xa
2: 4c 89 ef mov %r13,%rdi
5: e8 cf 31 9b ff call 0xff9b31d9
a: 4d 8b 6d 00 mov 0x0(%r13),%r13
e: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
15: fc ff df
18: 41 0f b6 04 06 movzbl (%r14,%rax,1),%eax
1d: 84 c0 test %al,%al
1f: 75 77 jne 0x98
21: 41 8b 17 mov (%r15),%edx
24: 4c 89 e7 mov %r12,%rdi
27: 4c 89 ee mov %r13,%rsi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 4c 8b 6c 24 28 mov 0x28(%rsp),%r13
34: e9 59 fe ff ff jmp 0xfffffe92
39: e8 db fa 8b 08 call 0x88bfb19
3e: 44 rex.R
3f: 89 .byte 0x89