syzbot


WARNING in ext4_xattr_inode_lookup_create

Status: upstream: reported C repro on 2025/07/31 23:44
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+116ea5ac2d7f27405104@syzkaller.appspotmail.com
First crash: 27d, last: 9d05h
Bug presence (1)
Date Name Commit Repro Result
2025/08/03 upstream (ToT) 186f3edfdd41 C [report] WARNING in ext4_xattr_inode_lookup_create
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in ext4_xattr_inode_lookup_create origin:upstream -1 C 177 4d23h 80d 0/3 upstream: reported C repro on 2025/06/08 17:41
upstream WARNING in ext4_xattr_inode_lookup_create ext4 -1 C inconclusive 841 2h17m 456d 0/29 upstream: reported C repro on 2024/05/28 15:21

Sample crash report:
EXT4-fs warning (device loop0): ext4_xattr_inode_create:1486: refuse to create EA inode when umounting
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5895 at fs/ext4/xattr.c:1487 ext4_xattr_inode_create fs/ext4/xattr.c:1485 [inline]
WARNING: CPU: 0 PID: 5895 at fs/ext4/xattr.c:1487 ext4_xattr_inode_lookup_create+0x5be/0x1d80 fs/ext4/xattr.c:1605
Modules linked in:
CPU: 0 PID: 5895 Comm: syz-executor Not tainted 6.6.100-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:ext4_xattr_inode_create fs/ext4/xattr.c:1487 [inline]
RIP: 0010:ext4_xattr_inode_lookup_create+0x5be/0x1d80 fs/ext4/xattr.c:1605
Code: 4c 8b 7c 24 10 e9 12 0a 00 00 e8 2d ea 43 ff 48 89 df 48 c7 c6 bb df 5b 8c ba ce 05 00 00 48 c7 c1 60 d0 be 8a e8 52 56 fc ff <0f> 0b 49 c7 c6 ea ff ff ff 48 8b 5c 24 08 e9 fe 09 00 00 48 8d 78
RSP: 0018:ffffc900033073e0 EFLAGS: 00010246
RAX: 1861383e2d852400 RBX: ffff88802d34c000 RCX: 1861383e2d852400
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc900033075b0 R08: ffffc90003306fa7 R09: 1ffff92000660df4
R10: dffffc0000000000 R11: fffff52000660df5 R12: ffff888072e852e8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888072e852b0
FS:  000055558a37f500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff5c99dd38 CR3: 000000007f74a000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 ext4_xattr_block_set+0x23e/0x32a0 fs/ext4/xattr.c:1925
 ext4_xattr_move_to_block fs/ext4/xattr.c:2674 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2749 [inline]
 ext4_expand_extra_isize_ea+0x10ea/0x19e0 fs/ext4/xattr.c:2841
 __ext4_expand_extra_isize+0x306/0x400 fs/ext4/inode.c:5953
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5996 [inline]
 __ext4_mark_inode_dirty+0x45d/0x6e0 fs/ext4/inode.c:6074
 ext4_dirty_inode+0xcb/0x110 fs/ext4/inode.c:6106
 __mark_inode_dirty+0x2b4/0xc80 fs/fs-writeback.c:2455
 mark_inode_dirty_sync include/linux/fs.h:2309 [inline]
 iput+0x1cc/0x920 fs/inode.c:1843
 __dentry_kill+0x431/0x650 fs/dcache.c:611
 shrink_dentry_list+0x39f/0x6a0 fs/dcache.c:1206
 shrink_dcache_parent+0xac/0x3c0 fs/dcache.c:-1
 do_one_tree+0x23/0xe0 fs/dcache.c:1686
 shrink_dcache_for_umount+0x69/0x110 fs/dcache.c:1703
 generic_shutdown_super+0x67/0x2b0 fs/super.c:665
 kill_block_super+0x44/0x90 fs/super.c:1660
 ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7396
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9bd338fe97
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fff5c99e4e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f9bd3411bdd RCX: 00007f9bd338fe97
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff5c99e5a0
RBP: 00007fff5c99e5a0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff5c99f630
R13: 00007f9bd3411bdd R14: 0000000000019ce5 R15: 00007fff5c99f670
 </TASK>

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/01 07:50 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/19 09:50 linux-6.6.y bb9c90ab9c5a 523f460e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/16 23:25 linux-6.6.y bb9c90ab9c5a 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/06 07:38 linux-6.6.y 3a8ababb8b6a ffe1dd46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/05 18:34 linux-6.6.y 3a8ababb8b6a 37880f40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/05 05:00 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/05 05:00 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/05 05:00 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/05 05:00 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/08/05 05:00 linux-6.6.y 3a8ababb8b6a f5bcc8dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/07/31 23:47 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/07/31 23:47 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/07/31 23:47 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/07/31 23:46 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/07/31 23:44 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/07/31 23:44 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/07/31 23:44 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
2025/07/31 23:44 linux-6.6.y dbcb8d8e4163 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_lookup_create
* Struck through repros no longer work on HEAD.