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: 397d, last: 13h45m
▶ ▼ 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 missing-backport -1 syz, C 2255 14h22m 397d 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 syz, C 5922 1h11m 400d 0/3 upstream: reported C repro on 2025/09/07 01:50
upstream WARNING in ext4_xattr_inode_update_ref ext4 -1 syz, C error 1291 347d 396d 29/29 fixed on 2025/10/29 21:02
upstream WARNING in ext4_xattr_inode_update_ref (2) prio:low ext4 -1 syz, C error 15604 38d 346d 27/29 upstream: reported C repro on 2025/10/30 22:34

Sample crash report:
EXT4-fs error (device loop0): ext4_map_blocks:631: inode #11: block 4559633: comm syz.0.17: lblock 3 mapped to illegal pblock 4559633 (length 1)
EXT4-fs (loop0): Remounting filesystem read-only
EXT4-fs warning (device loop0): ext4_expand_extra_isize_ea:2812: Unable to expand inode 15. Delete some EAs or run e2fsck.
------------[ cut here ]------------
EA inode 11 i_nlink=2
WARNING: CPU: 0 PID: 4323 at fs/ext4/xattr.c:1006 ext4_xattr_inode_update_ref+0x4fe/0x560 fs/ext4/xattr.c:1004
Modules linked in:
CPU: 0 PID: 4323 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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 55 01 a2 ff 49 8b 34 24 48 c7 c7 80 99 3d 8a 44 89 fa e8 a2 4d 99 07 <0f> 0b 49 bd 00 00 00 00 00 fc ff df 4c 8b 74 24 08 4c 8b 64 24 10
RSP: 0018:ffffc900022e7400 EFLAGS: 00010246
RAX: 7520b15eb1e08d00 RBX: ffff888068d50e90 RCX: ffff88802c22d940
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc900022e74f0 R08: ffff8880b902795b R09: 1ffff11017204f2b
R10: dffffc0000000000 R11: ffffed1017204f2c R12: ffff888068d50cd8
R13: dffffc0000000000 R14: ffff888068d50c98 R15: 0000000000000002
FS:  0000555568375500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562ddf928360 CR3: 000000007a2e5000 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+0x94c/0xf90 fs/ext4/xattr.c:1175
 ext4_xattr_delete_inode+0xada/0xca0 fs/ext4/xattr.c:2908
 ext4_evict_inode+0xc0c/0x1050 fs/ext4/inode.c:301
 evict+0x4b6/0x8b0 fs/inode.c:647
 ext4_orphan_cleanup+0xad8/0x1320 fs/ext4/orphan.c:472
 ext4_fill_super+0x8c65/0x93f0 fs/ext4/super.c:5006
 mount_bdev+0x28a/0x3c0 fs/super.c:1411
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1541
 do_new_mount+0x247/0xa40 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: 0033:0x7f78e0dfb3ca
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:00007ffe9480e638 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffe9480e6c0 RCX: 00007f78e0dfb3ca
RDX: 00002000000009c0 RSI: 0000200000000040 RDI: 00007ffe9480e680
RBP: 00002000000009c0 R08: 00007ffe9480e6c0 R09: 0000000000800718
R10: 0000000000800718 R11: 0000000000000246 R12: 0000200000000040
R13: 00007ffe9480e680 R14: 00000000000004a4 R15: 000000000000002c
 </TASK>

Crashes (3326):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/03 15:31 linux-5.15.y 0996e0926f6b 6a988719 .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
2026/03/21 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
2026/05/26 07:57 linux-5.15.y 241d66fa280c c69befb3 .config console log report syz / log [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
2026/04/12 20:19 linux-5.15.y 91d48252ad4b 38c8e246 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/11 20:14 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/11 13:12 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/11 11:54 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/11 08:11 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/10 13:17 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/10 11:30 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/10 10:22 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/10 09:27 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/10 03:00 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/10 02:34 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/10 01:33 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/10 00:09 linux-5.15.y a051a4bf909f 4f92358f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/09 00:48 linux-5.15.y a051a4bf909f b2734a59 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/08 23:31 linux-5.15.y a051a4bf909f b2734a59 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/08 03:17 linux-5.15.y a051a4bf909f 6520ecdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/08 03:17 linux-5.15.y a051a4bf909f 6520ecdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/07 19:36 linux-5.15.y a051a4bf909f 6520ecdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/07 18:27 linux-5.15.y a051a4bf909f 6520ecdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/07 17:04 linux-5.15.y a051a4bf909f 6520ecdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/07 16:54 linux-5.15.y a051a4bf909f 6520ecdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/06 07:57 linux-5.15.y a051a4bf909f f7710056 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/06 06:27 linux-5.15.y a051a4bf909f f7710056 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/05 19:46 linux-5.15.y a051a4bf909f af63e995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/05 06:23 linux-5.15.y a051a4bf909f 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/05 06:01 linux-5.15.y a051a4bf909f 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/04 13:24 linux-5.15.y a051a4bf909f 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/04 09:40 linux-5.15.y a051a4bf909f 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/04 04:54 linux-5.15.y a051a4bf909f 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/03 01:19 linux-5.15.y 0248c33e835e 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/03 00:14 linux-5.15.y 0248c33e835e 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/03 00:05 linux-5.15.y 0248c33e835e 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/02 15:56 linux-5.15.y 0248c33e835e 6d32eb1f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/02 12:56 linux-5.15.y 0248c33e835e 6d32eb1f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/02 09:05 linux-5.15.y 0248c33e835e 6d32eb1f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/01 19:04 linux-5.15.y 0248c33e835e f5cdae2f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/01 10:15 linux-5.15.y 0248c33e835e 38f7f0d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/10/01 01:27 linux-5.15.y 0248c33e835e 38f7f0d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/30 14:33 linux-5.15.y 0248c33e835e 7808aef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/30 12:31 linux-5.15.y 0248c33e835e 7808aef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/30 00:00 linux-5.15.y 0248c33e835e 328436b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/29 10:32 linux-5.15.y 0248c33e835e 7bf4ea23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/29 10:25 linux-5.15.y 0248c33e835e 7bf4ea23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/09/29 08:37 linux-5.15.y 0248c33e835e 7bf4ea23 .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.