linux-kernel - Re: [syzbot] [ext4?] WARNING in ext4_xattr_inode_update

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <690c5278.050a0220.1e8caa.00b8.GAE@google.com>
Date: Wed, 05 Nov 2025 23:47:04 -0800
From: syzbot <syzbot+76916a45d2294b551fd9@...kaller.appspotmail.com>
To: linux-kernel@...r.kernel.org, lizhi.xu@...driver.com, 
	syzkaller-bugs@...glegroups.com
Subject: Re: [syzbot] [ext4?] WARNING in ext4_xattr_inode_update_ref (2)

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in ext4_xattr_inode_update_ref

loop0: detected capacity change from 0 to 512
EXT4-fs warning (device loop0): ext4_xattr_inode_get:546: inode #11: comm syz.0.17: ea_inode file size=0 entry size=6
EXT4-fs warning (device loop0): ext4_expand_extra_isize_ea:2853: Unable to expand inode 15. Delete some EAs or run e2fsck.
------------[ cut here ]------------
EA inode 11 i_nlink=2
WARNING: CPU: 0 PID: 6694 at fs/ext4/xattr.c:1058 ext4_xattr_inode_update_ref+0x51a/0x5b0 fs/ext4/xattr.c:1056
Modules linked in:
CPU: 0 UID: 0 PID: 6694 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:ext4_xattr_inode_update_ref+0x51a/0x5b0 fs/ext4/xattr.c:1056
Code: 48 b8 00 00 00 00 00 fc ff df 41 0f b6 04 06 84 c0 0f 85 80 00 00 00 41 8b 17 48 c7 c7 00 9b ff 8a 4c 89 e6 e8 97 9a 03 ff 90 <0f> 0b 90 90 4c 8b 6c 24 28 e9 59 fe ff ff e8 33 f6 40 08 44 89 f9
RSP: 0018:ffffc90003a4f240 EFLAGS: 00010246
RAX: 9784c33726edfd00 RBX: 0000000000000001 RCX: ffff888020bb8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003a4f330 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed101710487b R12: 000000000000000b
R13: ffff888059283f88 R14: 1ffff1100b2507d7 R15: ffff888059283eb8
FS:  00007f0477f2e6c0(0000) GS:ffff888126df9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7f5e2ee440 CR3: 0000000028ad6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 ext4_xattr_inode_dec_ref fs/ext4/xattr.c:1081 [inline]
 ext4_xattr_inode_dec_ref_all+0x867/0xda0 fs/ext4/xattr.c:1223
 ext4_xattr_delete_inode+0xa4c/0xc10 fs/ext4/xattr.c:2947
 ext4_evict_inode+0xac9/0xee0 fs/ext4/inode.c:271
 evict+0x504/0x9c0 fs/inode.c:810
 ext4_orphan_cleanup+0xc20/0x1460 fs/ext4/orphan.c:470
 __ext4_fill_super fs/ext4/super.c:5617 [inline]
 ext4_fill_super+0x593b/0x61f0 fs/ext4/super.c:5736
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
 vfs_get_tree+0x92/0x2b0 fs/super.c:1751
 fc_mount fs/namespace.c:1208 [inline]
 do_new_mount_fc fs/namespace.c:3651 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3727
 do_mount fs/namespace.c:4050 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4215
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f04788c076a
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:00007f0477f2de68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f0477f2def0 RCX: 00007f04788c076a
RDX: 0000200000000180 RSI: 00002000000001c0 RDI: 00007f0477f2deb0
RBP: 0000200000000180 R08: 00007f0477f2def0 R09: 0000000000800700
R10: 0000000000800700 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f0477f2deb0 R14: 000000000000046c R15: 0000200000000680
 </TASK>


Tested on:

commit:         dc77806c Merge tag 'rust-fixes-6.18' of git://git.kern..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15b64a92580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=41ad820f608cb833
dashboard link: https://syzkaller.appspot.com/bug?extid=76916a45d2294b551fd9
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1731617c580000