Description
In the Linux kernel, the following vulnerability has been resolved:
dm: fix unconditional IO throttle caused by REQ_PREFLUSH
When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush()
generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
which causes the flush_bio to be throttled by wbt_wait().
An example from v5.4, similar problem also exists in upstream:
crash> bt 2091206
PID: 2091206 TASK: ffff2050df92a300 CPU: 109 COMMAND: "kworker/u260:0"
#0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8
#1 [ffff800084a2f820] __schedule at ffff800040bfa0c4
#2 [ffff800084a2f880] schedule at ffff800040bfa4b4
#3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4
#4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc
#5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0
#6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254
#7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38
#8 [ffff800084a2fa60] generic_make_request at ffff800040570138
#9 [ffff800084a2fae0] submit_bio at ffff8000405703b4
#10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs]
#11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs]
#12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs]
#13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs]
#14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs]
#15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs]
#16 [ffff800084a2fdb0] process_one_work at ffff800040111d08
#17 [ffff800084a2fe00] worker_thread at ffff8000401121cc
#18 [ffff800084a2fe70] kthread at ffff800040118de4
After commit 2def2845cc33 ("xfs: don't allow log IO to be throttled"),
the metadata submitted by xlog_write_iclog() should not be throttled.
But due to the existence of the dm layer, throttling flush_bio indirectly
causes the metadata bio to be throttled.
Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes
wbt_should_throttle() return false to avoid wbt_wait().
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 4.10 | 6.1.141 |
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 | 6.12.32-1 | — |
| Debian 13 | linux | 6.12.32-1 | — |
| Debian 12 | linux | 6.1.147-1 | DSA-5973-1 |
| Debian 11 | linux-6.1 | 6.1.153-1~deb11u1 | DLA-4328-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1016.20 | — |
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | No fix yet | — |
| Ubuntu 25.10 | linux-azure-fde | No fix yet | — |
| Ubuntu 25.04 | linux-azure | 6.14.0-1012.12 | USN-7770-1 |
| Ubuntu 25.04 | linux-raspi | 6.14.0-1014.14 | USN-7789-2 |
| Ubuntu 24.04 LTS | linux | 6.8.0-100.100 | USN-8028-1 |
| Ubuntu 24.04 LTS | linux-aws +1 | 6.8.0-1046.49 | USN-8028-5 |
| Ubuntu 24.04 LTS | linux-aws-6.14 +1 | 6.14.0-1013.13~24.04.1 | USN-7789-1, USN-7769-3 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1046.52 | USN-8074-1 |
| Ubuntu 24.04 LTS | linux-azure-fde | 6.8.0-1046.53 | — |
| Ubuntu 24.04 LTS | linux-azure-nvidia | 6.8.0-1039.42 | — |
| Ubuntu 24.04 LTS | linux-azure-nvidia-6.14 | 6.14.0-1007.7 | — |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1047.50 | USN-8031-3 |
| Ubuntu 24.04 LTS | linux-gcp-6.14 | 6.14.0-1016.17~24.04.1 | USN-7769-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1043.48 | USN-8031-3 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1030.33 | USN-8028-5 |
| Ubuntu 24.04 LTS | linux-hwe-6.14 | 6.14.0-32.32~24.04.1 | USN-7769-3 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1044.44 | USN-8028-8 |
| Ubuntu 24.04 LTS | linux-intel +10 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-100.100.1 | USN-8052-1 |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1046.49.1 | USN-8028-7 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1020.20 | — |
| Ubuntu 24.04 LTS | linux-oem-6.14 | 6.14.0-1012.12 | USN-7771-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1043.44 | USN-8028-5 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1047.51 | USN-8028-1 |
| Ubuntu 24.04 LTS | linux-riscv-6.14 | 6.14.0-32.32.1~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1023.24 | USN-8052-2 |
Show 17 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | linux +49 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-aws-6.8 +1 | 6.8.0-1046.49~22.04.1 | USN-8028-5 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1051.57~22.04.1 | USN-8126-1 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1046.53~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1047.50~22.04.2 | USN-8031-1 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 +1 | 6.8.0-100.100~22.04.1 | USN-8028-6 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1044.44~22.04.1 | USN-8028-8 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-100.100.1~22.04.1 | USN-8028-6 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1043.44~22.04.1 | USN-8028-5 |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| 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 | 6.8.0-2037.38 | USN-8028-3 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1041.42 | USN-8028-3 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | 6.14.0-1012.12~24.04.1 | USN-7769-2 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime +1 | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1041.42~22.04.1 | USN-8028-2 |
| 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-updates 24.04 LTS | linux-aws-fips | 6.8.0-1046.49+fips1 | USN-8028-4 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1046.52+fips1 | USN-8074-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-100.100+fips1 | USN-8028-4 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1047.50+fips1 | USN-8031-2 |
| Ubuntu Pro FIPS-updates 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux +21 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | linux +12 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | linux-gcp +4 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | linux-azure | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +5 | 6.4.0-150700.53.11.1 | SUSE-SU-2025:02997-1 |
| SLES 15 SP7 | kernel-azure +2 | 6.4.0-150700.20.11.1 | SUSE-SU-2025:03011-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.11.1.150700.17.9.4 | SUSE-SU-2025:02997-1 |
| SLES 15 SP7 | kernel-docs | 6.4.0-150700.53.11.3 | SUSE-SU-2025:02997-1 |
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.65.1 | SUSE-SU-2025:02996-1 |
| SLES 15 SP6 | kernel-azure +2 | 6.4.0-150600.8.48.1 | SUSE-SU-2025:02969-1 |
| SLES 15 SP6 | kernel-coco +3 | 6.4.0-15061.28.coco15sp6.1 | SUSE-SU-2025:02923-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.65.1.150600.12.28.4 | SUSE-SU-2025:02996-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 6.1 | kernel-default-base | 6.4.0-32.1.21.10 | SUSE-SU-2025:20602-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-35.1 | SUSE-SU-2025:20601-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-32.1 | SUSE-SU-2025:20602-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-32.1.21.10 | SUSE-SU-2025:20586-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-35.1 | SUSE-SU-2025:20577-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-32.1 | SUSE-SU-2025:20586-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.11.1 | SUSE-SU-2025:02997-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_3 | 1-150700.1.5.1 | SUSE-SU-2025:02853-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_3 | 1-150700.15.3.4 | SUSE-SU-2025:02997-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.65.1 | SUSE-SU-2025:02996-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6-RT_Update_14 | 1-150600.1.5.1 | SUSE-SU-2025:03023-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_14 | 1-150600.13.3.4 | SUSE-SU-2025:02996-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.13.1 | SUSE-SU-2025:02853-1 |
| SUSE Real Time Module 15 SP6 | kernel-rt +3 | 6.4.0-150600.10.49.1 | SUSE-SU-2025:03023-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.6 | dtb-aarch64 +10 | 6.4.0-150600.23.65.1 | SUSE-SU-2025:02996-1 |
| openSUSE Leap 15.6 | kernel-azure +2 | 6.4.0-150600.8.48.1 | SUSE-SU-2025:02969-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.65.1.150600.12.28.4 | SUSE-SU-2025:02996-1 |
| openSUSE Leap 15.6 | kernel-rt +3 | 6.4.0-150600.10.49.1 | SUSE-SU-2025:03023-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.12.31-35.92 +1 | 1.0-0.amzn2023 | ALAS2023-2025-1052, ALAS2023-2025-1037 |
| Amazon Linux 2023 | perf +14 | 6.1.141-155.222.amzn2023 | ALAS2023-2025-1052, ALAS2023-2025-1037 |
| Amazon Linux 2023 | perf6.12 +5 | 6.12.31-35.92.amzn2023 | ALAS2023-2025-1052 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.96.1-1 | — |
| Azure Linux 2 (CBL-Mariner) | kernel | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-101.33.4.3.el10uek | ELSA-2025-20530, ELSA-2025-20480 |
Advisories 43
- WID-SEC-2025-1350 Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8028-5 linux-aws, linux-aws-6.8, linux-gkeop, linux-nvidia, linux-nvidia-6.8, linux-oracle, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8126-1 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-8 linux-ibm, linux-ibm-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-6 linux-hwe-6.8, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8052-1 linux-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8052-2 linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8074-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8074-2 linux-azure-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8031-3 linux-gcp, linux-gke vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-1 linux, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-4 linux-aws-fips, linux-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-3 linux-realtime, linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-7 linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-2 linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8031-2 linux-gcp-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8031-1 linux-gcp-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7789-1 linux-oracle-6.14 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7769-2 linux-realtime-6.14 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7771-1 linux-oem-6.14 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7769-1 linux, linux-aws, linux-gcp, linux-gcp-6.14, linux-oracle, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-7769-3 linux-aws-6.14, linux-hwe-6.14 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- SSA-082556 SSA-082556: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.5 Siemens ProductCERT · Oct 13, 2026
- ICSA-25-162-05 Siemens SIMATIC S7-1500 CPU family CISA ICS & IT advisories · May 14, 2026
- SUSE-SU-2025:20601-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20602-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02997-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20586-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20577-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:03011-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02996-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- DLA-4328-1 linux-6.1 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-5973-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-7789-2 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Feb 4, 2026
- SUSE-SU-2025:02853-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:02923-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- USN-7770-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Feb 4, 2026
- SUSE-SU-2025:02969-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:03023-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- ALAS2023-2025-1052 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Sep 10, 2025
- ALAS2023-2025-1037 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 26, 2025
- ELSA-2025-20530 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Aug 18, 2025
- ELSA-2025-20480 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 17, 2025
References
- https://git.kernel.org/stable/c/95d08924335f3b6f4ea0b92ebfe4fe0731c502d9
- https://git.kernel.org/stable/c/52aa28f7b1708d76e315d78b5ed397932a1a97c3
- https://git.kernel.org/stable/c/b55a97d1bd4083729a60d19beffe85d4c96680de
- https://git.kernel.org/stable/c/2858cda9a8d95e6deee7e3b0a26adde696a9a4f5
- https://git.kernel.org/stable/c/88f7f56d16f568f19e1a695af34a7f4a6ce537a6