syzbot


WARNING in ext4_xattr_block_set

Status: upstream: reported C repro on 2025/09/16 07:25
Reported-by: syzbot+b1aa832f28aa881188a3@syzkaller.appspotmail.com
First crash: 19h21m, last: 18h43m
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in ext4_xattr_block_set (3) ext4 -1 C error 12 11h28m 6h37m 0/29 upstream: reported C repro on 2025/09/16 20:09
upstream WARNING in ext4_xattr_block_set ext4 -1 C error 57 941d 1047d 22/29 fixed on 2023/02/24 13:50
upstream WARNING in ext4_xattr_block_set (2) ext4 -1 C error 32 858d 923d 22/29 fixed on 2023/07/01 16:05

Sample crash report:
syz.0.17[5951]: memfd_create() called without MFD_EXEC or MFD_NOEXEC_SEAL set
loop0: detected capacity change from 0 to 512
EXT4-fs (loop0): orphan cleanup on readonly fs
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5951 at fs/ext4/xattr.c:1923 ext4_xattr_block_set+0x2a7a/0x32a0 fs/ext4/xattr.c:1923
Modules linked in:
CPU: 0 PID: 5951 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:ext4_xattr_block_set+0x2a7a/0x32a0 fs/ext4/xattr.c:1923
Code: ff 48 8b 5c 24 18 48 8d 7b 28 be 08 00 00 00 e8 bc c6 9a ff f0 80 63 28 fd eb 1b e8 b0 79 43 ff e9 2f f1 ff ff e8 a6 79 43 ff <0f> 0b e9 72 d7 ff ff e8 9a 79 43 ff 48 b8 00 00 00 00 00 fc ff df
RSP: 0018:ffffc900032f72a0 EFLAGS: 00010293
RAX: ffffffff8242169a RBX: ffffc900032f75a8 RCX: ffff8880219c3c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900032f7490 R08: 00000000ffffffc3 R09: 00000000ffffffc3
R10: ffff888059cd3400 R11: ffff888059cd3020 R12: 0000000000000000
R13: 1ffff9200065eeb6 R14: 1ffff9200065eeb5 R15: ffffc900032f75b0
FS:  00005555873e6500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558617c853d0 CR3: 0000000018e9d000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 ext4_xattr_move_to_block fs/ext4/xattr.c:2674 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2749 [inline]
 ext4_expand_extra_isize_ea+0x10ea/0x19e0 fs/ext4/xattr.c:2841
 __ext4_expand_extra_isize+0x306/0x400 fs/ext4/inode.c:5953
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5996 [inline]
 __ext4_mark_inode_dirty+0x45d/0x6e0 fs/ext4/inode.c:6074
 ext4_evict_inode+0x7ed/0xea0 fs/ext4/inode.c:252
 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: 0033:0x7fea3759034a
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:00007ffdeae1a8c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffdeae1a950 RCX: 00007fea3759034a
RDX: 0000200000000180 RSI: 00002000000001c0 RDI: 00007ffdeae1a910
RBP: 0000200000000180 R08: 00007ffdeae1a950 R09: 000000000080078b
R10: 000000000080078b R11: 0000000000000246 R12: 00002000000001c0
R13: 00007ffdeae1a910 R14: 0000000000000473 R15: 0000200000000680
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/16 08:03 linux-6.6.y 60a9e718726f e2beed91 .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_block_set
2025/09/16 07:44 linux-6.6.y 60a9e718726f e2beed91 .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_block_set
2025/09/16 07:26 linux-6.6.y 60a9e718726f e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_block_set
2025/09/16 07:25 linux-6.6.y 60a9e718726f e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in ext4_xattr_block_set
* Struck through repros no longer work on HEAD.