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WARNING in ext4_xattr_inode_update_ref

Status: upstream: reported C repro on 2025/09/10 09:56
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+b56a869e22ff21696a84@syzkaller.appspotmail.com
First crash: 193d, last: 18h00m
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2025/09/12 upstream (ToT) 320475fbd590 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 -1 C 1305 11h25m 193d 0/2 upstream: reported C repro on 2025/09/10 09:46
linux-6.1 WARNING in ext4_xattr_inode_update_ref origin:upstream -1 C 3515 1h00m 196d 0/3 upstream: reported C repro on 2025/09/07 01:50
upstream WARNING in ext4_xattr_inode_update_ref ext4 -1 C error 1291 144d 192d 29/29 fixed on 2025/10/29 21:02
upstream WARNING in ext4_xattr_inode_update_ref (2) ext4 -1 C error 5865 9m 142d 0/29 upstream: reported C repro on 2025/10/30 22:34

Sample crash report:
loop0: detected capacity change from 0 to 512
EXT4-fs (loop0): Warning: mounting with an experimental mount option 'dioread_nolock' for blocksize < PAGE_SIZE
------------[ cut here ]------------
EA inode 11 i_nlink=0
WARNING: CPU: 0 PID: 4314 at fs/ext4/xattr.c:1006 ext4_xattr_inode_update_ref+0x4e7/0x540 fs/ext4/xattr.c:1004
Modules linked in:
CPU: 0 PID: 4314 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:ext4_xattr_inode_update_ref+0x4e7/0x540 fs/ext4/xattr.c:1004
Code: 7c 24 40 4c 89 f8 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 1a e6 a1 ff 49 8b 37 48 c7 c7 40 9b 3d 8a 89 da e8 f9 32 95 07 <0f> 0b 4c 8b 64 24 08 4c 8b 7c 24 10 e9 a9 fe ff ff e8 43 22 a0 07
RSP: 0018:ffffc90002eaf160 EFLAGS: 00010246
RAX: 71896f62f0db1800 RBX: 0000000000000000 RCX: ffff888027a09dc0
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90002eaf250 R08: ffff8880b902795b R09: 1ffff11017204f2b
R10: dffffc0000000000 R11: ffffed1017204f2c R12: ffff88806e737048
R13: 1ffff1100dce6e48 R14: dffffc0000000000 R15: ffff88806e737088
FS:  0000555561172500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0ed995ed30 CR3: 000000005ec84000 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_set_entry+0xed9/0x3ea0 fs/ext4/xattr.c:1685
 ext4_xattr_ibody_set+0x112/0x330 fs/ext4/xattr.c:2238
 ext4_xattr_move_to_block fs/ext4/xattr.c:2625 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2693 [inline]
 ext4_expand_extra_isize_ea+0x10d3/0x19b0 fs/ext4/xattr.c:2781
 __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: 0033:0x7f1551581a0a
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:00007ffdd4d4fa78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffdd4d4fb00 RCX: 00007f1551581a0a
RDX: 0000200000000180 RSI: 0000200000000000 RDI: 00007ffdd4d4fac0
RBP: 0000200000000180 R08: 00007ffdd4d4fb00 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000000
R13: 00007ffdd4d4fac0 R14: 000000000000047a R15: 0000200000000b40
 </TASK>

Crashes (1957):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/21 20:50 linux-5.15.y 91d48252ad4b 5b92003d .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/12 05:16 linux-5.15.y 91d48252ad4b 2d88ab01 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/10 23:38 linux-5.15.y 91d48252ad4b 4683d576 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/08 20:27 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/01 13:44 linux-5.15.y 3330a8d33e08 43249bac .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/25 22:14 linux-5.15.y 3330a8d33e08 94a9671e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/23 20:30 linux-5.15.y 3330a8d33e08 6beca497 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/20 15:35 linux-5.15.y 3330a8d33e08 17d780d6 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/18 02:03 linux-5.15.y e45d5d41c134 06ec4f7b .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/09 07:21 linux-5.15.y 7b232985052f 4c131dc4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/07 09:58 linux-5.15.y 7b232985052f f20fc9f9 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/05 20:55 linux-5.15.y 9eec9a14ee10 4936e85c .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro #1 (corrupt fs)] [mounted in repro #2 (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/04 13:14 linux-5.15.y 9eec9a14ee10 42b01fab .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/03 07:40 linux-5.15.y 9eec9a14ee10 d78927dd .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/01 09:16 linux-5.15.y 9eec9a14ee10 6b8752f2 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/01/25 07:43 linux-5.15.y 9eec9a14ee10 40acda8a .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/01/23 06:58 linux-5.15.y 9eec9a14ee10 82c9c083 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/10 21:01 linux-5.15.y de9476bb4f1b fdeaa69b .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/22 03:46 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/21 20:34 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/21 16:20 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/21 12:56 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/21 09:08 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/20 23:33 linux-5.15.y 91d48252ad4b ac6f1dff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/20 22:59 linux-5.15.y 91d48252ad4b ac6f1dff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/20 08:37 linux-5.15.y 91d48252ad4b 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/20 08:31 linux-5.15.y 91d48252ad4b 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/19 20:57 linux-5.15.y 91d48252ad4b bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/19 18:45 linux-5.15.y 91d48252ad4b bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/19 05:15 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/19 02:25 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/19 02:22 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/18 18:26 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/18 17:19 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/18 17:15 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/18 09:32 linux-5.15.y 91d48252ad4b c8810548 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/18 02:38 linux-5.15.y 91d48252ad4b c8810548 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/17 17:17 linux-5.15.y 91d48252ad4b c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/17 16:01 linux-5.15.y 91d48252ad4b c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/12 02:23 linux-5.15.y 91d48252ad4b 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/11 09:16 linux-5.15.y 91d48252ad4b 86914af9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/10 09:31 linux-5.15.y 91d48252ad4b 6972f302 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/10 08:03 linux-5.15.y 91d48252ad4b 6972f302 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/09 09:12 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/08 19:49 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/08 08:56 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/08 08:49 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/08 04:46 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/07 15:35 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/07 06:58 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/05 20:05 linux-5.15.y 91d48252ad4b d20b04c8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/04 20:55 linux-5.15.y 91d48252ad4b e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/04 09:50 linux-5.15.y 3330a8d33e08 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/04 09:17 linux-5.15.y 3330a8d33e08 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/04 05:14 linux-5.15.y 3330a8d33e08 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/03 20:28 linux-5.15.y 3330a8d33e08 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/02 06:32 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/01 12:49 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/03/01 09:58 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/28 19:57 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/28 09:09 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/27 05:54 linux-5.15.y 3330a8d33e08 a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/26 18:27 linux-5.15.y 3330a8d33e08 ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/25 16:56 linux-5.15.y 3330a8d33e08 94a9671e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/02/24 17:12 linux-5.15.y 3330a8d33e08 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/10 09:55 linux-5.15.y de9476bb4f1b fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
* Struck through repros no longer work on HEAD.