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: 349d, last: 11h08m
▶ ▼ 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 syz, C 2013 1h58m 349d 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 5347 37m 353d 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 300d 349d 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 15378 3h25m 299d 19/29 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 (3000):
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
2026/05/26 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
2026/08/25 21:52 linux-5.15.y 945fa863f02c a9a1fc32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/25 18:55 linux-5.15.y 945fa863f02c a9a1fc32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/24 21:12 linux-5.15.y 945fa863f02c b55bd4c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/24 08:41 linux-5.15.y 945fa863f02c 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/23 21:25 linux-5.15.y 945fa863f02c 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/23 03:28 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/23 02:27 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/22 19:12 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/22 19:07 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/22 17:58 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/20 19:44 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/20 16:32 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/19 08:23 linux-5.15.y aabd761612db 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/19 06:00 linux-5.15.y aabd761612db 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/18 19:03 linux-5.15.y aabd761612db 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/18 15:06 linux-5.15.y aabd761612db 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/18 07:53 linux-5.15.y aabd761612db 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/18 06:16 linux-5.15.y aabd761612db 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/18 06:07 linux-5.15.y aabd761612db 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/17 18:09 linux-5.15.y aabd761612db 905244d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/16 19:36 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/16 11:07 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/16 09:47 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/15 18:00 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/15 17:59 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/15 06:54 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/13 12:19 linux-5.15.y aabd761612db 359b2492 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/12 09:12 linux-5.15.y aabd761612db f8d35649 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/11 23:28 linux-5.15.y aabd761612db 71790083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/11 19:50 linux-5.15.y aabd761612db 71790083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/11 02:18 linux-5.15.y aabd761612db 508909ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/11 02:17 linux-5.15.y aabd761612db 508909ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/10 13:09 linux-5.15.y aabd761612db 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/10 03:34 linux-5.15.y aabd761612db 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/09 16:55 linux-5.15.y aabd761612db 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/09 09:53 linux-5.15.y aabd761612db 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/07 01:47 linux-5.15.y 9c7634c60784 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/06 00:44 linux-5.15.y 6e2fd6534337 cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/05 09:58 linux-5.15.y 6e2fd6534337 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/04 04:18 linux-5.15.y 6e2fd6534337 9451e17e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/03 07:44 linux-5.15.y 6e2fd6534337 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/02 20:30 linux-5.15.y 6e2fd6534337 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/02 20:30 linux-5.15.y 6e2fd6534337 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/02 18:11 linux-5.15.y 6e2fd6534337 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/02 10:16 linux-5.15.y 6e2fd6534337 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in ext4_xattr_inode_update_ref
2026/08/02 06:47 linux-5.15.y 6e2fd6534337 e611ffe1 .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.