Description
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix warning in 'ext4_da_release_space'
Syzkaller report issue as follows:
EXT4-fs (loop0): Free/Dirty block details
EXT4-fs (loop0): free_blocks=0
EXT4-fs (loop0): dirty_blocks=0
EXT4-fs (loop0): Block reservation details
EXT4-fs (loop0): i_reserved_data_blocks=0
EXT4-fs warning (device loop0): ext4_da_release_space:1527: ext4_da_release_space: ino 18, to_free 1 with only 0 reserved data blocks
------------[ cut here ]------------
WARNING: CPU: 0 PID: 92 at fs/ext4/inode.c:1528 ext4_da_release_space+0x25e/0x370 fs/ext4/inode.c:1524
Modules linked in:
CPU: 0 PID: 92 Comm: kworker/u4:4 Not tainted 6.0.0-syzkaller-09423-g493ffd6605b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:ext4_da_release_space+0x25e/0x370 fs/ext4/inode.c:1528
RSP: 0018:ffffc900015f6c90 EFLAGS: 00010296
RAX: 42215896cd52ea00 RBX: 0000000000000000 RCX: 42215896cd52ea00
RDX: 0000000000000000 RSI: 0000000080000001 RDI: 0000000000000000
RBP: 1ffff1100e907d96 R08: ffffffff816aa79d R09: fffff520002bece5
R10: fffff520002bece5 R11: 1ffff920002bece4 R12: ffff888021fd2000
R13: ffff88807483ecb0 R14: 0000000000000001 R15: ffff88807483e740
FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555569ba628 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ext4_es_remove_extent+0x1ab/0x260 fs/ext4/extents_status.c:1461
mpage_release_unused_pages+0x24d/0xef0 fs/ext4/inode.c:1589
ext4_writepages+0x12eb/0x3be0 fs/ext4/inode.c:2852
do_writepages+0x3c3/0x680 mm/page-writeback.c:2469
__writeback_single_inode+0xd1/0x670 fs/fs-writeback.c:1587
writeback_sb_inodes+0xb3b/0x18f0 fs/fs-writeback.c:1870
wb_writeback+0x41f/0x7b0 fs/fs-writeback.c:2044
wb_do_writeback fs/fs-writeback.c:2187 [inline]
wb_workfn+0x3cb/0xef0 fs/fs-writeback.c:2227
process_one_work+0x877/0xdb0 kernel/workqueue.c:2289
worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
kthread+0x266/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
Above issue may happens as follows:
ext4_da_write_begin
ext4_create_inline_data
ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
ext4_set_inode_flag(inode, EXT4_INODE_INLINE_DATA);
__ext4_ioctl
ext4_ext_migrate -> will lead to eh->eh_entries not zero, and set extent flag
ext4_da_write_begin
ext4_da_convert_inline_data_to_extent
ext4_da_write_inline_data_begin
ext4_da_map_blocks
ext4_insert_delayed_block
if (!ext4_es_scan_clu(inode, &ext4_es_is_delonly, lblk))
if (!ext4_es_scan_clu(inode, &ext4_es_is_mapped, lblk))
ext4_clu_mapped(inode, EXT4_B2C(sbi, lblk)); -> will return 1
allocated = true;
ext4_es_insert_delayed_block(inode, lblk, allocated);
ext4_writepages
mpage_map_and_submit_extent(handle, &mpd, &give_up_on_write); -> return -ENOSPC
mpage_release_unused_pages(&mpd, give_up_on_write); -> give_up_on_write == 1
ext4_es_remove_extent
ext4_da_release_space(inode, reserved);
if (unlikely(to_free > ei->i_reserved_data_blocks))
-> to_free == 1 but ei->i_reserved_data_blocks == 0
-> then trigger warning as above
To solve above issue, forbid inode do migrate which has inline data.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 3.8 | 4.9.333 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 6.0.8-1 | — |
| Debian 13 | linux | 6.0.8-1 | — |
| Debian 12 | linux | 6.0.8-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | 5.15.0-1014.16 | — |
| Ubuntu 24.04 LTS | linux-realtime +1 | No fix yet | — |
| Ubuntu 22.04 LTS | linux +1 | 5.15.0-60.66 | — |
| Ubuntu 22.04 LTS | linux-aws | 5.15.0-1030.34 | — |
| Ubuntu 22.04 LTS | linux-azure | 5.15.0-1033.40 | — |
| Ubuntu 22.04 LTS | linux-azure-fde | 5.15.0-1033.40.1 | — |
| Ubuntu 22.04 LTS | linux-gcp | 5.15.0-1029.36 | — |
| Ubuntu 22.04 LTS | linux-gke | 5.15.0-1027.32 | — |
| Ubuntu 22.04 LTS | linux-gkeop | 5.15.0-1015.19 | — |
| Ubuntu 22.04 LTS | linux-ibm | 5.15.0-1025.28 | — |
| Ubuntu 22.04 LTS | linux-intel-iotg | 5.15.0-1025.30 | — |
| Ubuntu 22.04 LTS | linux-kvm | 5.15.0-1028.33 | — |
| Ubuntu 22.04 LTS | linux-nvidia | 5.15.0-1017.17 | — |
| Ubuntu 22.04 LTS | linux-oracle | 5.15.0-1029.35 | — |
| Ubuntu 22.04 LTS | linux-raspi | 5.15.0-1024.26 | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux | 5.4.0-139.156 | — |
| Ubuntu 20.04 LTS | linux-aws | 5.4.0-1096.104 | — |
| Ubuntu 20.04 LTS | linux-aws-5.15 | 5.15.0-1030.34~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-azure | 5.4.0-1103.109 | — |
| Ubuntu 20.04 LTS | linux-azure-5.15 | 5.15.0-1033.40~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-bluefield | 5.4.0-1058.64 | — |
| Ubuntu 20.04 LTS | linux-gcp | 5.4.0-1100.109 | — |
| Ubuntu 20.04 LTS | linux-gcp-5.15 | 5.15.0-1029.36~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-hwe-5.15 +1 | 5.15.0-60.66~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-ibm | 5.4.0-1044.49 | — |
| Ubuntu 20.04 LTS | linux-intel-iotg-5.15 | 5.15.0-1025.30~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-iot | 5.4.0-1012.14 | — |
| Ubuntu 20.04 LTS | linux-kvm | 5.4.0-1086.92 | — |
| Ubuntu 20.04 LTS | linux-oracle | 5.4.0-1093.102 | — |
| Ubuntu 20.04 LTS | linux-oracle-5.15 | 5.15.0-1029.35~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-raspi | 5.4.0-1080.91 | — |
| Ubuntu 20.04 LTS | linux-riscv-5.15 | 5.15.0-1029.33~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-xilinx-zynqmp | 5.4.0-1021.25 | — |
| Ubuntu 18.04 LTS | linux | 4.15.0-206.217 | — |
| Ubuntu 18.04 LTS | linux-aws | 4.15.0-1151.164 | — |
| Ubuntu 18.04 LTS | linux-aws-5.4 | 5.4.0-1096.104~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-azure-4.15 | 4.15.0-1162.177 | — |
| Ubuntu 18.04 LTS | linux-azure-5.4 | 5.4.0-1103.109~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp-4.15 | 4.15.0-1146.162 | — |
| Ubuntu 18.04 LTS | linux-gcp-5.4 | 5.4.0-1100.109~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-hwe-5.4 | 5.4.0-139.156~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-ibm-5.4 | 5.4.0-1044.49~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-kvm | 4.15.0-1136.141 | — |
| Ubuntu 18.04 LTS | linux-oracle | 4.15.0-1115.126 | — |
| Ubuntu 18.04 LTS | linux-oracle-5.4 | 5.4.0-1093.102~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-raspi-5.4 | 5.4.0-1080.91~18.04.1 | — |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro FIPS 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS 18.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS 16.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-aws-fips | 5.4.0-1096.104+fips1 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-azure-fips | 5.4.0-1103.109+fips1 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-fips | 5.4.0-1072.81 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-gcp-fips | 5.4.0-1100.109+fips1 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-aws-fips | 4.15.0-2090.96 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-azure-fips | 4.15.0-2071.77 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-fips | 4.15.0-1108.119 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-gcp-fips | 4.15.0-2055.60 | — |
| Ubuntu Pro FIPS-updates 16.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro 16.04 LTS | linux +2 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | linux-aws-hwe | 4.15.0-1151.164~16.04.1 | — |
| Ubuntu Pro 16.04 LTS | linux-azure | 4.15.0-1162.177~16.04.1 | — |
| Ubuntu Pro 16.04 LTS | linux-gcp | 4.15.0-1146.162~16.04.1 | — |
| Ubuntu Pro 16.04 LTS | linux-hwe | 4.15.0-206.217~16.04.1 | — |
| Ubuntu Pro 16.04 LTS | linux-oracle | 4.15.0-1115.126~16.04.1 | — |
| Ubuntu Pro 14.04 LTS | linux +2 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | linux-azure | 4.15.0-1162.177~14.04.1 | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | kernel-64kb +6 | 5.14.21-150500.55.110.1 | SUSE-SU-2025:02173-1 |
| SLES 15 SP5 | kernel-default-base | 5.14.21-150500.55.110.1.150500.6.51.3 | SUSE-SU-2025:02173-1 |
| SLES 15 SP4 | kernel-64kb +6 | 5.14.21-150400.24.167.1 | SUSE-SU-2025:02262-1 |
| SLES 15 SP4 | kernel-default-base | 5.14.21-150400.24.167.1.150400.24.84.1 | SUSE-SU-2025:02262-1 |
| SLES 15 SP3 | kernel-64kb +7 | 5.3.18-150300.59.207.1 | SUSE-SU-2025:01982-1 |
| SLES 15 SP3 | kernel-default-base | 5.3.18-150300.59.207.1.150300.18.124.1 | SUSE-SU-2025:01982-1 |
| SLES 12 SP5 | kernel-syms +2 | 4.12.14-122.261.1 | SUSE-SU-2025:01983-1 |
Show 18 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP5 | kernel-default-base | 5.14.21-150500.55.110.1.150500.6.51.3 | SUSE-SU-2025:02173-1 |
| SLES for SAP 15 SP5 | kernel-docs +4 | 5.14.21-150500.55.110.1 | SUSE-SU-2025:02173-1 |
| SLES for SAP 15 SP4 | kernel-default-base | 5.14.21-150400.24.167.1.150400.24.84.1 | SUSE-SU-2025:02262-1 |
| SLES for SAP 15 SP4 | kernel-docs +4 | 5.14.21-150400.24.167.1 | SUSE-SU-2025:02262-1 |
| SLES for SAP 15 SP3 | kernel-default-base | 5.3.18-150300.59.207.1.150300.18.124.1 | SUSE-SU-2025:01982-1 |
| SLES for SAP 15 SP3 | kernel-docs +5 | 5.3.18-150300.59.207.1 | SUSE-SU-2025:01982-1 |
| SLE Micro 5.5 | kernel-default-base | 5.14.21-150500.55.110.1.150500.6.51.3 | SUSE-SU-2025:02173-1 |
| SLE Micro 5.5 | kernel-rt +1 | 5.14.21-150500.13.97.1 | SUSE-SU-2025:01966-1 |
| SLE Micro 5.5 | kernel-source +1 | 5.14.21-150500.55.110.1 | SUSE-SU-2025:02173-1 |
| SLE Micro 5.4 | kernel-default | 5.14.21-150400.24.167.1 | SUSE-SU-2025:02262-1 |
| SLE Micro 5.4 | kernel-default-base | 5.14.21-150400.24.167.1.150400.24.84.1 | SUSE-SU-2025:02262-1 |
| SLE Micro 5.4 | kernel-rt +1 | 5.14.21-150400.15.121.1 | SUSE-SU-2025:01918-1 |
| SLE Micro 5.3 | kernel-default | 5.14.21-150400.24.167.1 | SUSE-SU-2025:02262-1 |
| SLE Micro 5.3 | kernel-default-base | 5.14.21-150400.24.167.1.150400.24.84.1 | SUSE-SU-2025:02262-1 |
| SLE Micro 5.3 | kernel-rt +1 | 5.14.21-150400.15.121.1 | SUSE-SU-2025:01918-1 |
| SLE Micro 5.2 | kernel-default | 5.3.18-150300.59.207.1 | SUSE-SU-2025:01982-1 |
| SLE Micro 5.2 | kernel-default-base | 5.3.18-150300.59.207.1.150300.18.124.1 | SUSE-SU-2025:01982-1 |
| SLE Micro 5.2 | kernel-rt +1 | 5.3.18-150300.211.1 | SUSE-SU-2025:01995-1 |
| SLE Micro 5.1 | kernel-default | 5.3.18-150300.59.207.1 | SUSE-SU-2025:01982-1 |
| SLE Micro 5.1 | kernel-default-base | 5.3.18-150300.59.207.1.150300.18.124.1 | SUSE-SU-2025:01982-1 |
| SLE Micro 5.1 | kernel-rt +1 | 5.3.18-150300.211.1 | SUSE-SU-2025:01995-1 |
| SLE Live Patching 15 SP5 | kernel-default | 5.14.21-150500.55.110.1 | SUSE-SU-2025:02173-1 |
| SLE Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5_Update_27 | 1-150500.11.7.1 | SUSE-SU-2025:02173-1 |
| SLE Live Patching 15 SP4 | kernel-default | 5.14.21-150400.24.167.1 | SUSE-SU-2025:02262-1 |
| SLE Live Patching 15 SP4 | kernel-livepatch-SLE15-SP4_Update_41 | 1-150400.9.3.1 | SUSE-SU-2025:02262-1 |
| SLE Live Patching 15 SP3 | kernel-default | 5.3.18-150300.59.207.1 | SUSE-SU-2025:01982-1 |
| SLE Live Patching 15 SP3 | kernel-livepatch-SLE15-SP3_Update_58 | 1-150300.7.3.1 | SUSE-SU-2025:01982-1 |
| SLE Live Patching 12 SP5 | kernel-default | 4.12.14-122.261.1 | SUSE-SU-2025:01983-1 |
| SLE Live Patching 12 SP5 | kgraft-patch-SLE12-SP5_Update_69 | 1-8.3.1 | SUSE-SU-2025:01983-1 |
| SLE HPC 15 SP5 | kernel-64kb +5 | 5.14.21-150500.55.110.1 | SUSE-SU-2025:02173-1 |
| SLE HPC 15 SP5 | kernel-default-base | 5.14.21-150500.55.110.1.150500.6.51.3 | SUSE-SU-2025:02173-1 |
| SLE HPC 15 SP4 | kernel-64kb +5 | 5.14.21-150400.24.167.1 | SUSE-SU-2025:02262-1 |
| SLE HPC 15 SP4 | kernel-default-base | 5.14.21-150400.24.167.1.150400.24.84.1 | SUSE-SU-2025:02262-1 |
| SLE HPC 15 SP3 | kernel-64kb +6 | 5.3.18-150300.59.207.1 | SUSE-SU-2025:01982-1 |
| SLE HPC 15 SP3 | kernel-default-base | 5.3.18-150300.59.207.1.150300.18.124.1 | SUSE-SU-2025:01982-1 |
| SUSE Manager Server 4.3 | kernel-default-base | 5.14.21-150400.24.167.1.150400.24.84.1 | SUSE-SU-2025:02262-1 |
| SUSE Manager Server 4.3 | kernel-syms +3 | 5.14.21-150400.24.167.1 | SUSE-SU-2025:02262-1 |
| SUSE Manager Proxy 4.3 | kernel-default-base | 5.14.21-150400.24.167.1.150400.24.84.1 | SUSE-SU-2025:02262-1 |
| SUSE Manager Proxy 4.3 | kernel-syms +2 | 5.14.21-150400.24.167.1 | SUSE-SU-2025:02262-1 |
| SUSE Enterprise Storage 7.1 | kernel-64kb +6 | 5.3.18-150300.59.207.1 | SUSE-SU-2025:01982-1 |
| SUSE Enterprise Storage 7.1 | kernel-default-base | 5.3.18-150300.59.207.1.150300.18.124.1 | SUSE-SU-2025:01982-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | kernel-livepatch-4.14.299-223.520 | 1.0-0.amzn2 | ALAS2-2022-1888 |
| Amazon Linux 2 | perf +8 | 4.14.299-223.520.amzn2 | ALAS2-2022-1888 |
Advisories 9
- WID-SEC-2025-0922 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- SUSE-SU-2025:01995-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02262-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:01918-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:02173-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:01966-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:01982-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:01983-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- ALAS2-2022-1888 Important: kernel security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Dec 19, 2025
References
- https://git.kernel.org/stable/c/0de5ee103747fd3a24f1c010c79caabe35e8f0bb
- https://git.kernel.org/stable/c/c3bf1e95cfa7d950dc3c064d0c2e3d06b427bc63
- https://git.kernel.org/stable/c/890d738f569fa9412b70ba09f15407f17a52da20
- https://git.kernel.org/stable/c/72743d5598b9096950bbfd6a9b7f173d156eea97
- https://git.kernel.org/stable/c/5370b965b7a945bb8f48b9ee23d83a76a947902e
- https://git.kernel.org/stable/c/0a43c015e98121c91a76154edf42280ce1a8a883
- https://git.kernel.org/stable/c/89bee03d2fb8c54119b38ac6c24e7d60fae036b6
- https://git.kernel.org/stable/c/1b8f787ef547230a3249bcf897221ef0cc78481b