Description
In the Linux kernel, the following vulnerability has been resolved:
ublk: fix deadlock when reading partition table
When one process(such as udev) opens ublk block device (e.g., to read
the partition table via bdev_open()), a deadlock[1] can occur:
1. bdev_open() grabs disk->open_mutex
2. The process issues read I/O to ublk backend to read partition table
3. In __ublk_complete_rq(), blk_update_request() or blk_mq_end_request()
runs bio->bi_end_io() callbacks
4. If this triggers fput() on file descriptor of ublk block device, the
work may be deferred to current task's task work (see fput() implementation)
5. This eventually calls blkdev_release() from the same context
6. blkdev_release() tries to grab disk->open_mutex again
7. Deadlock: same task waiting for a mutex it already holds
The fix is to run blk_update_request() and blk_mq_end_request() with bottom
halves disabled. This forces blkdev_release() to run in kernel work-queue
context instead of current task work context, and allows ublk server to make
forward progress, and avoids the deadlock.
[axboe: rewrite comment in ublk]
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.0 | 6.1.175 |
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 | 6.12.73-1 | DSA-6141-1 |
| Debian 12 | linux | 6.1.176-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1022.26 | — |
| 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 | 6.8.0-117.117 | USN-8278-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1055.58 | USN-8278-1 |
| 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 | 6.8.0-1056.62 | USN-8278-2 |
| Ubuntu 24.04 LTS | linux-azure-6.17 | 6.17.0-1013.13~24.04.1 | USN-8245-1 |
| Ubuntu 24.04 LTS | linux-azure-fde | 6.8.0-1058.65 | — |
| Ubuntu 24.04 LTS | linux-azure-nvidia | 6.8.0-1039.42 | — |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1058.61 | USN-8278-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1054.60 | USN-8278-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1041.44 | USN-8278-1 |
| Ubuntu 24.04 LTS | linux-hwe-6.17 | 6.17.0-22.22~24.04.1 | USN-8183-2 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1055.56 | USN-8278-1 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-117.117.1 | USN-8278-1 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1054.57 | USN-8289-1 |
| Ubuntu 24.04 LTS | linux-nvidia-6.17 | 6.17.0-1018.18 | — |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1054.57.1 | USN-8289-1 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1024.24 | USN-8296-2 |
| Ubuntu 24.04 LTS | linux-oem-6.17 | 6.17.0-1020.20 | USN-8245-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1054.55 | — |
| Ubuntu 24.04 LTS | linux-oracle-6.17 | 6.17.0-1011.11~24.04.1 | USN-8183-2 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1056.60 | USN-8278-1 |
| 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 24.04 LTS | linux-xilinx | 6.8.0-1032.33 | USN-8499-1 |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1057.60~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1059.65~22.04.1 | USN-8440-1 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1058.65~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1060.63~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-hwe-6.8 | 6.8.0-124.124~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1055.56~22.04.1 | USN-8278-1 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-117.117.1~22.04.1 | USN-8278-1 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1054.57~22.04.1 | USN-8289-2 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1054.55~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv-6.8 | 6.8.0-117.117~22.04.1 | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2045.46 | USN-8278-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1051.52 | USN-8278-1 |
| 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 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1051.52~22.04.1 | USN-8278-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1055.58+fips1 | USN-8278-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1059.65+fips1 | USN-8393-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-116.116+fips1 | USN-8296-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1058.61+fips1 | USN-8278-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-200.74.27.el10uek | ELSA-2026-50160 |
Advisories 17
- WID-SEC-2026-0086 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8440-1 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8499-1 linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8393-1 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8278-1 linux, linux-aws, linux-aws-fips, linux-gcp, linux-gcp-fips, linux-gke, linux-gkeop, linux-ibm, linux-ibm-6.8, linux-lowlatency, linux-lowlatency-hwe-6.8, linux-raspi, linux-raspi-realtime, linux-realtime, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 5, 2026
- USN-8289-1 linux-nvidia, linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 5, 2026
- USN-8289-2 linux-nvidia-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 5, 2026
- USN-8278-2 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 5, 2026
- USN-8296-1 linux-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 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-8296-2 linux-nvidia-tegra 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
- ELSA-2026-50160 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Mar 20, 2026
- DSA-6141-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- https://git.kernel.org/stable/c/27bb79b7717b2fbb111a1c13548b2786ee712dca
- https://git.kernel.org/stable/c/64c0b7e2293757e8320f13434cd809f1c9257a62
- https://git.kernel.org/stable/c/9bcc47343ee0ef346aa7b2b460c8ff56bd882fe7
- https://git.kernel.org/stable/c/0460e09a614291f06c008443f47393c37b7358e7
- https://git.kernel.org/stable/c/c258f5c4502c9667bccf5d76fa731ab9c96687c1