Description
In the Linux kernel, the following vulnerability has been resolved:
btrfs: avoid NULL pointer dereference if no valid csum tree
[BUG]
When trying read-only scrub on a btrfs with rescue=idatacsums mount
option, it will crash with the following call trace:
BUG: kernel NULL pointer dereference, address: 0000000000000208
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
CPU: 1 UID: 0 PID: 835 Comm: btrfs Tainted: G O 6.15.0-rc3-custom+ #236 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
RIP: 0010:btrfs_lookup_csums_bitmap+0x49/0x480 [btrfs]
Call Trace:
<TASK>
scrub_find_fill_first_stripe+0x35b/0x3d0 [btrfs]
scrub_simple_mirror+0x175/0x290 [btrfs]
scrub_stripe+0x5f7/0x6f0 [btrfs]
scrub_chunk+0x9a/0x150 [btrfs]
scrub_enumerate_chunks+0x333/0x660 [btrfs]
btrfs_scrub_dev+0x23e/0x600 [btrfs]
btrfs_ioctl+0x1dcf/0x2f80 [btrfs]
__x64_sys_ioctl+0x97/0xc0
do_syscall_64+0x4f/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e
[CAUSE]
Mount option "rescue=idatacsums" will completely skip loading the csum
tree, so that any data read will not find any data csum thus we will
ignore data checksum verification.
Normally call sites utilizing csum tree will check the fs state flag
NO_DATA_CSUMS bit, but unfortunately scrub does not check that bit at all.
This results in scrub to call btrfs_search_slot() on a NULL pointer
and triggered above crash.
[FIX]
Check both extent and csum tree root before doing any tree search.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 5.9 | 6.1.191 |
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 | No fix yet | — |
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 10 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-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-preview 22.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro 20.04 LTS | linux-aws-5.15 +10 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +6 | 6.4.0-150700.53.6.1 | SUSE-SU-2025:02307-1 |
| SLES 15 SP7 | kernel-azure +2 | 6.4.0-150700.20.6.1 | SUSE-SU-2025:02254-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.6.1.150700.17.6.1 | SUSE-SU-2025:02307-1 |
| SLES 15 SP6 | kernel-64kb +3 | 6.4.0-150600.23.60.4 | SUSE-SU-2025:02538-1 |
| SLES 15 SP6 | kernel-azure +2 | 6.4.0-150600.8.43.1 | SUSE-SU-2025:02249-1 |
| SLES 15 SP6 | kernel-coco +3 | 6.4.0-15061.28.coco15sp6.1 | SUSE-SU-2025:02923-1 |
| SLES 15 SP6 | kernel-default | 6.4.0-150600.23.60.5 | SUSE-SU-2025:02538-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.60.5.150600.12.26.4 | SUSE-SU-2025:02538-1 |
| SLES 15 SP6 | kernel-docs +1 | 6.4.0-150600.23.60.3 | SUSE-SU-2025:02538-1 |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 6.1 | kernel-default-base | 6.4.0-31.1.21.9 | SUSE-SU-2025:20475-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-34.1 | SUSE-SU-2025:20483-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-31.1 | SUSE-SU-2025:20475-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-31.1.21.9 | SUSE-SU-2025:20493-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-34.1 | SUSE-SU-2025:20498-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-31.1 | SUSE-SU-2025:20493-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.6.1 | SUSE-SU-2025:02307-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_2 | 1-150700.1.5.1 | SUSE-SU-2025:02333-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_2 | 1-150700.15.3.1 | SUSE-SU-2025:02307-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.60.5 | SUSE-SU-2025:02538-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6-RT_Update_13 | 1-150600.1.5.1 | SUSE-SU-2025:02335-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_13 | 1-150600.13.6.4 | SUSE-SU-2025:02538-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.8.1 | SUSE-SU-2025:02333-1 |
| SUSE Real Time Module 15 SP6 | kernel-rt +3 | 6.4.0-150600.10.44.1 | SUSE-SU-2025:02335-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.6 | dtb-aarch64 +2 | 6.4.0-150600.23.60.3 | SUSE-SU-2025:02538-1 |
| openSUSE Leap 15.6 | kernel-64kb +5 | 6.4.0-150600.23.60.4 | SUSE-SU-2025:02538-1 |
| openSUSE Leap 15.6 | kernel-azure +2 | 6.4.0-150600.8.43.1 | SUSE-SU-2025:02249-1 |
| openSUSE Leap 15.6 | kernel-default | 6.4.0-150600.23.60.5 | SUSE-SU-2025:02538-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.60.5.150600.12.26.4 | SUSE-SU-2025:02538-1 |
| openSUSE Leap 15.6 | kernel-obs-qa | 6.4.0-150600.23.60.2 | SUSE-SU-2025:02538-1 |
| openSUSE Leap 15.6 | kernel-rt +3 | 6.4.0-150600.10.44.1 | SUSE-SU-2025:02335-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | bpftool +14 | 6.12.31-35.92.amzn2023 | ALAS2023-2025-1052 |
| Amazon Linux 2023 | kernel-livepatch-6.12.31-35.92 | 1.0-0.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 38
- 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-8028-2 linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
- USN-8028-7 linux-nvidia-lowlatency 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
- SUSE-SU-2025:20475-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20493-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02335-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02254-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20483-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:20498-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02333-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02307-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:02249-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- USN-7789-2 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · 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-2025:02538-1 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
- 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/2db25048a61c0909459b074af04e06ab8a8b939e
- https://git.kernel.org/stable/c/50d0de59f66cbe6d597481e099bf1c70fd07e0a9
- https://git.kernel.org/stable/c/6e9770de024964b1017f99ee94f71967bd6edaeb
- https://git.kernel.org/stable/c/d35bed14b0bc95c6845863a3744ecd10b888c830
- https://git.kernel.org/stable/c/f95d186255b319c48a365d47b69bd997fecb674e