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WARNING in ext4_xattr_block_set

Status: upstream: reported C repro on 2025/09/18 02:40
Reported-by: syzbot+e0bc42dc6050f6711adb@syzkaller.appspotmail.com
First crash: 7h58m, last: 3h42m
▶ ▼ Similar bugs (4)
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 17 3h00m 1d14h 0/29 upstream: reported C repro on 2025/09/16 20:09
upstream WARNING in ext4_xattr_block_set ext4 -1 C error 57 942d 1048d 22/29 fixed on 2023/02/24 13:50
upstream WARNING in ext4_xattr_block_set (2) ext4 -1 C error 32 860d 924d 22/29 fixed on 2023/07/01 16:05
linux-6.6 WARNING in ext4_xattr_block_set -1 C 6 5h45m 2d03h 0/2 upstream: reported C repro on 2025/09/16 07:25

Sample crash report:
loop0: detected capacity change from 0 to 512
EXT4-fs (loop0): orphan cleanup on readonly fs
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4539 at fs/ext4/xattr.c:1874 ext4_xattr_block_set+0x2010/0x2810 fs/ext4/xattr.c:1874
Modules linked in:
CPU: 1 PID: 4539 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ext4_xattr_block_set+0x2010/0x2810 fs/ext4/xattr.c:1874
lr : ext4_xattr_block_set+0x2010/0x2810 fs/ext4/xattr.c:1874
sp : ffff800021466f20
x29: ffff800021467090 x28: ffff0000d2dcc700 x27: ffff8000214671e0
x26: dfff800000000000 x25: ffff0000e9863500 x24: ffff0000d2dcc700
x23: 1ffff0000428ce3e x22: 1ffff0000428ce3d x21: 0000000000000000
x20: ffff8000214671f0 x19: ffff8000214671e8 x18: ffff800011abbcc0
x17: ffff8000181fa000 x16: ffff8000082d0e30 x15: 0000000000000000
x14: 00000000ffffffc3 x13: 00000000ffffffc3 x12: 0000000000ff0100
x11: ff00800008e51e50 x10: 0000000000000000 x9 : ffff800008e51e50
x8 : ffff0000cfe58000 x7 : ffff0000ead30000 x6 : ffff0000ead30020
x5 : ffff800021467020 x4 : ffff0000d2dcc728 x3 : ffff800008e4fef8
x2 : 0000000000000028 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
 ext4_xattr_block_set+0x2010/0x2810 fs/ext4/xattr.c:1874
 ext4_xattr_move_to_block fs/ext4/xattr.c:2625 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2700 [inline]
 ext4_expand_extra_isize_ea+0xcb8/0x15cc fs/ext4/xattr.c:2792
 __ext4_expand_extra_isize+0x298/0x358 fs/ext4/inode.c:5966
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6009 [inline]
 __ext4_mark_inode_dirty+0x3e4/0x790 fs/ext4/inode.c:6087
 ext4_evict_inode+0xb58/0x1270 fs/ext4/inode.c:279
 evict+0x3c8/0x810 fs/inode.c:705
 iput_final fs/inode.c:1834 [inline]
 iput+0x764/0x7f4 fs/inode.c:1860
 ext4_process_orphan+0x240/0x2b4 fs/ext4/orphan.c:360
 ext4_orphan_cleanup+0x908/0x104c fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5537 [inline]
 ext4_fill_super+0x6920/0x6e34 fs/ext4/super.c:5668
 get_tree_bdev+0x358/0x544 fs/super.c:1366
 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5698
 vfs_get_tree+0x90/0x274 fs/super.c:1573
 do_new_mount+0x228/0x810 fs/namespace.c:3069
 path_mount+0x5b4/0xe78 fs/namespace.c:3399
 do_mount fs/namespace.c:3412 [inline]
 __do_sys_mount fs/namespace.c:3620 [inline]
 __se_sys_mount fs/namespace.c:3597 [inline]
 __arm64_sys_mount+0x49c/0x584 fs/namespace.c:3597
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 4170
hardirqs last  enabled at (4169): [<ffff800008a7b970>] lookup_bh_lru fs/buffer.c:1291 [inline]
hardirqs last  enabled at (4169): [<ffff800008a7b970>] __find_get_block+0x1c8/0xdfc fs/buffer.c:1303
hardirqs last disabled at (4170): [<ffff8000119576b0>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (2682): [<ffff80000803092c>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (2680): [<ffff8000080308f8>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
EA inode 11 i_nlink=2
WARNING: CPU: 1 PID: 4539 at fs/ext4/xattr.c:1021 ext4_xattr_inode_update_ref+0x468/0x4ac fs/ext4/xattr.c:-1
Modules linked in:
CPU: 1 PID: 4539 Comm: syz.0.17 Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ext4_xattr_inode_update_ref+0x468/0x4ac fs/ext4/xattr.c:-1
lr : ext4_xattr_inode_update_ref+0x464/0x4ac fs/ext4/xattr.c:1019
sp : ffff800021466e80
x29: ffff800021466f00 x28: 0000000000000000 x27: dfff800000000000
x26: 1fffe0001d30ca9d x25: ffff70000428cdd0 x24: 0000000000000000
x23: ffff800017a8b000 x22: ffff800021466e80 x21: 0000000000000002
x20: 0000000000000001 x19: ffff0000e98652f0 x18: ffff800011abbcc0
x17: 0000000000000000 x16: ffff8000082d22e0 x15: 0000000000000000
x14: 00000000ffffffff x13: 0000000000000001 x12: 0000000000ff0100
x11: ff00800008191ca8 x10: 0000000000000000 x9 : 102dec1ba5f53300
x8 : 102dec1ba5f53300 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800021466918 x4 : ffff8000151a4820 x3 : ffff800008311d00
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000000
Call trace:
 ext4_xattr_inode_update_ref+0x468/0x4ac fs/ext4/xattr.c:-1
 ext4_xattr_inode_dec_ref fs/ext4/xattr.c:1044 [inline]
 ext4_xattr_set_entry+0x918/0x15ac fs/ext4/xattr.c:1682
 ext4_xattr_ibody_set+0x204/0x600 fs/ext4/xattr.c:2229
 ext4_xattr_move_to_block fs/ext4/xattr.c:2632 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2700 [inline]
 ext4_expand_extra_isize_ea+0xd00/0x15cc fs/ext4/xattr.c:2792
 __ext4_expand_extra_isize+0x298/0x358 fs/ext4/inode.c:5966
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6009 [inline]
 __ext4_mark_inode_dirty+0x3e4/0x790 fs/ext4/inode.c:6087
 ext4_evict_inode+0xb58/0x1270 fs/ext4/inode.c:279
 evict+0x3c8/0x810 fs/inode.c:705
 iput_final fs/inode.c:1834 [inline]
 iput+0x764/0x7f4 fs/inode.c:1860
 ext4_process_orphan+0x240/0x2b4 fs/ext4/orphan.c:360
 ext4_orphan_cleanup+0x908/0x104c fs/ext4/orphan.c:474
 __ext4_fill_super fs/ext4/super.c:5537 [inline]
 ext4_fill_super+0x6920/0x6e34 fs/ext4/super.c:5668
 get_tree_bdev+0x358/0x544 fs/super.c:1366
 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5698
 vfs_get_tree+0x90/0x274 fs/super.c:1573
 do_new_mount+0x228/0x810 fs/namespace.c:3069
 path_mount+0x5b4/0xe78 fs/namespace.c:3399
 do_mount fs/namespace.c:3412 [inline]
 __do_sys_mount fs/namespace.c:3620 [inline]
 __se_sys_mount fs/namespace.c:3597 [inline]
 __arm64_sys_mount+0x49c/0x584 fs/namespace.c:3597
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 4348
hardirqs last  enabled at (4347): [<ffff800008308424>] __up_console_sem+0xb4/0x100 kernel/printk/printk.c:261
hardirqs last disabled at (4348): [<ffff8000119576b0>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (4242): [<ffff8000081a967c>] softirq_handle_end kernel/softirq.c:439 [inline]
softirqs last  enabled at (4242): [<ffff8000081a967c>] handle_softirqs+0xaf8/0xc6c kernel/softirq.c:624
softirqs last disabled at (4173): [<ffff800008020164>] __do_softirq+0x14/0x20 kernel/softirq.c:630
---[ end trace 0000000000000000 ]---
EXT4-fs (loop0): 1 orphan inode deleted
EXT4-fs (loop0): mounted filesystem without journal. Quota mode: none.

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/18 02:55 linux-6.1.y 3db754f56897 e2beed91 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_block_set
2025/09/18 06:55 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_block_set
2025/09/18 06:55 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in ext4_xattr_block_set
2025/09/18 02:51 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_block_set
2025/09/18 02:39 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ext4_xattr_block_set
* Struck through repros no longer work on HEAD.