syzbot


WARNING in ext4_xattr_inode_update_ref

Status: upstream: reported C repro on 2025/09/10 09:46
Reported-by: syzbot+48f1b5af9d99f72922d5@syzkaller.appspotmail.com
First crash: 1d06h, last: 15h16m
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in ext4_xattr_inode_update_ref origin:upstream -1 C 27 12h22m 4d14h 0/3 upstream: reported C repro on 2025/09/07 01:50
upstream WARNING in ext4_xattr_inode_update_ref ext4 -1 C error 55 11h32m 15h59m 0/29 upstream: reported C repro on 2025/09/11 00:08
linux-5.15 WARNING in ext4_xattr_inode_update_ref -1 C 13 13h12m 1d06h 0/3 upstream: reported C repro on 2025/09/10 09:56

Sample crash report:
EXT4-fs warning (device loop0): ext4_xattr_inode_get:559: inode #11: comm syz.0.17: EA inode hash validation failed
EXT4-fs warning (device loop0): ext4_expand_extra_isize_ea:2867: Unable to expand inode 15. Delete some EAs or run e2fsck.
------------[ cut here ]------------
EA inode 11 ref_count=-1
WARNING: CPU: 1 PID: 5947 at fs/ext4/xattr.c:1065 ext4_xattr_inode_update_ref+0x483/0x580 fs/ext4/xattr.c:1064
Modules linked in:
CPU: 1 PID: 5947 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:ext4_xattr_inode_update_ref+0x483/0x580 fs/ext4/xattr.c:1064
Code: 24 50 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 cf 43 9a ff 49 8b 36 48 c7 c7 c0 ce be 8a 48 89 da e8 ad 74 0d ff <0f> 0b 4c 8b 64 24 18 48 8b 5c 24 10 4c 8d 7c 24 60 e9 d0 fe ff ff
RSP: 0018:ffffc90003337340 EFLAGS: 00010246
RAX: 4ab653cd1c2bb300 RBX: ffffffffffffffff RCX: ffff88801f70bc00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc90003337430 R08: ffffc90003336f47 R09: 1ffff92000666de8
R10: dffffc0000000000 R11: fffff52000666de9 R12: ffff88805fc43eb0
R13: dffffc0000000000 R14: ffff88805fc43f00 R15: ffffc900033373a0
FS:  00005555799c7500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f699773f000 CR3: 0000000078d0a000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 ext4_xattr_inode_dec_ref fs/ext4/xattr.c:1093 [inline]
 ext4_xattr_inode_dec_ref_all+0xa2b/0xf90 fs/ext4/xattr.c:1235
 ext4_xattr_delete_inode+0xa45/0xc00 fs/ext4/xattr.c:2963
 ext4_evict_inode+0xaa3/0xea0 fs/ext4/inode.c:269
 evict+0x486/0x870 fs/inode.c:705
 ext4_orphan_cleanup+0xbd4/0x1400 fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5608 [inline]
 ext4_fill_super+0x5de7/0x66c0 fs/ext4/super.c:5731
 get_tree_bdev+0x3e4/0x510 fs/super.c:1591
 vfs_get_tree+0x8c/0x280 fs/super.c:1764
 do_new_mount+0x24b/0xa40 fs/namespace.c:3377
 do_mount fs/namespace.c:3717 [inline]
 __do_sys_mount fs/namespace.c:3926 [inline]
 __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3903
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fac3079034a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff6788f5b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fff6788f640 RCX: 00007fac3079034a
RDX: 0000200000000180 RSI: 00002000000001c0 RDI: 00007fff6788f600
RBP: 0000200000000180 R08: 00007fff6788f640 R09: 000000000080078b
R10: 000000000080078b R11: 0000000000000246 R12: 00002000000001c0
R13: 00007fff6788f600 R14: 0000000000000473 R15: 0000200000000680
 </TASK>

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/10 22:48 linux-6.6.y fe9731e10004 fdeaa69b .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/11 00:51 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/11 00:49 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/10 09:58 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/10 09:58 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/10 09:54 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/10 09:53 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/10 09:45 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
2025/09/10 09:45 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_inode_update_ref
* Struck through repros no longer work on HEAD.