Description
In the Linux kernel, the following vulnerability has been resolved:
md: init bioset in mddev_init
IO operations may be needed before md_run(), such as updating metadata
after writing sysfs. Without bioset, this triggers a NULL pointer
dereference as below:
BUG: kernel NULL pointer dereference, address: 0000000000000020
Call Trace:
md_update_sb+0x658/0xe00
new_level_store+0xc5/0x120
md_attr_store+0xc9/0x1e0
sysfs_kf_write+0x6f/0xa0
kernfs_fop_write_iter+0x141/0x2a0
vfs_write+0x1fc/0x5a0
ksys_write+0x79/0x180
__x64_sys_write+0x1d/0x30
x64_sys_call+0x2818/0x2880
do_syscall_64+0xa9/0x580
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Reproducer
```
mdadm -CR /dev/md0 -l1 -n2 /dev/sd[cd]
echo inactive > /sys/block/md0/md/array_state
echo 10 > /sys/block/md0/md/new_level
```
mddev_init() can only be called once per mddev, no need to test if bioset
has been initialized anymore.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.12 | 6.12.114 |
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 | 6.18.3-1 | — |
| Debian 13 | linux | 6.12.115-2 | — |
| Debian 12 | linux-6.12 | 6.12.115-2~deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 25.10 | linux | 6.17.0-22.22 | USN-8177-1 |
| Ubuntu 25.10 | linux-aws +1 | 6.17.0-1012.12 | USN-8183-2, USN-8183-1 |
| Ubuntu 25.10 | linux-azure +1 | 6.17.0-1013.13 | USN-8245-1 |
| Ubuntu 25.10 | linux-azure-fde | No fix yet | — |
| Ubuntu 25.10 | linux-oracle | 6.17.0-1011.11 | USN-8183-2 |
| Ubuntu 25.10 | linux-realtime | 6.17.0-1010.11 | USN-8177-1 |
| Ubuntu 25.10 | linux-riscv | 6.17.0-22.22.1 | — |
| Ubuntu 24.04 LTS | linux-aws-6.17 +1 | 6.17.0-1012.12~24.04.1 | USN-8183-2, USN-8183-1 |
| Ubuntu 24.04 LTS | linux-azure-6.17 | 6.17.0-1013.13~24.04.1 | USN-8245-1 |
| Ubuntu 24.04 LTS | linux-hwe-6.17 | 6.17.0-22.22~24.04.1 | USN-8183-2 |
| Ubuntu 24.04 LTS | linux-nvidia-6.17 | 6.17.0-1018.18 | — |
| Ubuntu 24.04 LTS | linux-oem-6.17 | 6.17.0-1020.20 | USN-8245-1 |
| Ubuntu 24.04 LTS | linux-oracle-6.17 | 6.17.0-1011.11~24.04.1 | USN-8183-2 |
| Ubuntu 24.04 LTS | linux-riscv +18 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-6.17 | 6.17.0-22.22.1~24.04.1 | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
Show 2 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 Realtime 24.04 LTS | linux-realtime-6.14 | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.17 | 6.17.0-1010.11~24.04.1 | USN-8177-2 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.26.1 | SUSE-SU-2026:20599-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20599-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.26.1 | SUSE-SU-2026:20615-1, SUSE-SU-2026:20599-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20599-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20555-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.26.1 | SUSE-SU-2026:20570-1, SUSE-SU-2026:20555-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 6.18.5-1.1 | openSUSE-SU-2026:10039-1 |
| openSUSE Tumbleweed | kernel-source-longterm | 6.18.16-1.1 | openSUSE-SU-2026:10301-1 |
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | openSUSE-SU-2026:20287-1 |
| openSUSE Leap 16.0 | kernel-rt +11 | 6.12.0-160000.26.1 | openSUSE-SU-2026:20287-1 |
Advisories 13
- WID-SEC-2025-2920 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8183-2 linux-aws, linux-aws-6.17, linux-hwe-6.17, linux-oracle, linux-oracle-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8183-1 linux-gcp, linux-gcp-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8245-1 linux-azure, linux-azure-6.17, linux-oem-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8177-2 linux-realtime-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8177-1 linux, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- SUSE-SU-2026:20570-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- openSUSE-SU-2026:20287-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2026:10039-1 kernel-devel-6.18.5-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20615-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20599-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20555-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2026:10301-1 kernel-devel-longterm-6.18.16-1.1 on GA media SUSE / openSUSE Security Updates · Mar 8, 2026