WARNING in ext4_xattr_inode_update_ref

Status: upstream: reported C repro on 2025/09/07 01:50
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+23ef1ff7166a7f106a9d@syzkaller.appspotmail.com
First crash: 388d, last: 14h18m
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2025/10/27 upstream (ToT) dcb6fa37fd7b C [report] WARNING in ext4_xattr_inode_update_ref
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 WARNING in ext4_xattr_inode_update_ref origin:upstream missing-backport -1 syz, C 2137 1h26m 384d 0/2 upstream: reported C repro on 2025/09/10 09:46
upstream WARNING in ext4_xattr_inode_update_ref ext4 -1 syz, C error 1291 335d 384d 29/29 fixed on 2025/10/29 21:02
linux-5.15 WARNING in ext4_xattr_inode_update_ref origin:upstream -1 syz, C 3174 5h21m 384d 0/3 upstream: reported C repro on 2025/09/10 09:56
upstream WARNING in ext4_xattr_inode_update_ref (2) prio:low ext4 -1 syz, C error 15604 26d 334d 27/29 upstream: reported C repro on 2025/10/30 22:34

Sample crash report:
loop0: detected capacity change from 0 to 512
EXT4-fs warning (device loop0): ext4_expand_extra_isize_ea:2802: Unable to expand inode 15. Delete some EAs or run e2fsck.
------------[ cut here ]------------
EA inode 11 i_nlink=2
WARNING: CPU: 0 PID: 4424 at fs/ext4/xattr.c:1006 ext4_xattr_inode_update_ref+0x4fe/0x560 fs/ext4/xattr.c:1004
Modules linked in:
CPU: 0 PID: 4424 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:ext4_xattr_inode_update_ref+0x4fe/0x560 fs/ext4/xattr.c:1004
Code: 40 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 85 e2 9b ff 49 8b 34 24 48 c7 c7 00 a0 a0 8a 44 89 fa e8 32 3a 16 ff <0f> 0b 49 bd 00 00 00 00 00 fc ff df 4c 8b 74 24 08 4c 8b 64 24 10
RSP: 0018:ffffc900034d7380 EFLAGS: 00010246
RAX: 83593f72d5615b00 RBX: ffff88806e7840d8 RCX: ffff888078c6da00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc900034d7470 R08: ffff8880b8e279db R09: 1ffff110171c4f3b
R10: dffffc0000000000 R11: ffffed10171c4f3c R12: ffff88806e783f20
R13: dffffc0000000000 R14: ffff88806e783ee0 R15: 0000000000000002
FS:  0000555556b3a500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbd7624cc6b CR3: 000000005c7bb000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_xattr_inode_dec_ref fs/ext4/xattr.c:1029 [inline]
 ext4_xattr_inode_dec_ref_all+0xadc/0x1050 fs/ext4/xattr.c:1175
 ext4_xattr_delete_inode+0xada/0xca0 fs/ext4/xattr.c:2898
 ext4_evict_inode+0xc1e/0x10e0 fs/ext4/inode.c:298
 evict+0x4b6/0x8b0 fs/inode.c:705
 ext4_orphan_cleanup+0xc32/0x1470 fs/ext4/orphan.c:472
 __ext4_fill_super fs/ext4/super.c:5574 [inline]
 ext4_fill_super+0x6f0c/0x78f0 fs/ext4/super.c:5693
 get_tree_bdev+0x3e6/0x610 fs/super.c:1366
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x247/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbd7619f10a
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:00007ffe65656e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffe65656ee0 RCX: 00007fbd7619f10a
RDX: 00002000000009c0 RSI: 0000200000000540 RDI: 00007ffe65656ea0
RBP: 00002000000009c0 R08: 00007ffe65656ee0 R09: 0000000000800718
R10: 0000000000800718 R11: 0000000000000246 R12: 0000200000000540
R13: 00007ffe65656ea0 R14: 000000000000048d R15: 0000200000000200
 </TASK>

Crashes (5661):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/26 15:02 linux-6.1.y dc5c83b7f5f8 492bab15 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/22 13:02 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/04 11:57 linux-6.1.y cd9b81672742 42b01fab .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/01/16 17:38 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/01/15 12:59 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/01/14 11:22 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/01/12 21:25 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2025/10/25 17:50 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/05/30 20:40 linux-6.1.y dcbcab9d7079 6b4a8443 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/02/23 09:03 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/02/18 23:19 linux-6.1.y 8ce36b2849ef 77d4d919 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/02/17 12:14 linux-6.1.y 8ce36b2849ef e439b951 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/02/16 22:20 linux-6.1.y 8ce36b2849ef 5d52cba5 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/02/15 01:29 linux-6.1.y 8ce36b2849ef 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/02/09 18:15 linux-6.1.y 0182cb5b74ee df949cd9 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/02/05 17:17 linux-6.1.y cd9b81672742 4936e85c .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/01/23 20:20 linux-6.1.y cd9b81672742 e2b1b6e6 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/01/22 16:25 linux-6.1.y cd9b81672742 a16aed1d .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/01/20 23:06 linux-6.1.y cd9b81672742 06648d9c .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/01/19 08:11 linux-6.1.y cd9b81672742 20d37d28 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/01/15 13:11 linux-6.1.y bec0e10ee67e d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/02/07 14:08 linux-6.1.y 0182cb5b74ee f20fc9f9 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/28 00:05 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/27 22:16 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/27 17:48 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/27 17:04 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/27 15:24 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/27 04:04 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/26 14:26 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/26 09:27 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/25 02:06 linux-6.1.y 1a8763b93150 3c3cdf19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/24 13:28 linux-6.1.y 1a8763b93150 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/24 07:21 linux-6.1.y 1a8763b93150 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/23 18:30 linux-6.1.y 1a8763b93150 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/23 06:59 linux-6.1.y 1a8763b93150 5207b90e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/23 05:08 linux-6.1.y 1a8763b93150 5207b90e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/19 22:01 linux-6.1.y 1a8763b93150 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/19 21:58 linux-6.1.y 1a8763b93150 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/19 19:08 linux-6.1.y 1a8763b93150 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/19 16:59 linux-6.1.y 1a8763b93150 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/19 14:43 linux-6.1.y 1a8763b93150 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/29 15:51 linux-6.1.y 1a8763b93150 7bf4ea23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/29 15:48 linux-6.1.y 1a8763b93150 7bf4ea23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/29 09:08 linux-6.1.y 1a8763b93150 7bf4ea23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/29 08:08 linux-6.1.y 1a8763b93150 7bf4ea23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/28 20:30 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/28 17:01 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/28 14:08 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/27 20:31 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/27 14:13 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/27 13:55 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/27 11:12 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/26 16:53 linux-6.1.y 1a8763b93150 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/25 13:43 linux-6.1.y 1a8763b93150 f281d9d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/25 09:21 linux-6.1.y 1a8763b93150 f281d9d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/24 22:02 linux-6.1.y 1a8763b93150 3c3cdf19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/24 12:10 linux-6.1.y 1a8763b93150 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/24 09:08 linux-6.1.y 1a8763b93150 0281b448 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/23 22:06 linux-6.1.y 1a8763b93150 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/23 18:49 linux-6.1.y 1a8763b93150 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/23 10:02 linux-6.1.y 1a8763b93150 5207b90e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/23 04:07 linux-6.1.y 1a8763b93150 5207b90e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/22 13:31 linux-6.1.y 1a8763b93150 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/19 15:56 linux-6.1.y 1a8763b93150 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2026/09/19 13:53 linux-6.1.y 1a8763b93150 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2025/09/07 02:01 linux-6.1.y 28c695c365e1 d291dd2d .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
2025/09/07 01:49 linux-6.1.y 28c695c365e1 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_inode_update_ref
* Struck through repros no longer work on HEAD.