UBUNTU-CVE-2025-68772: Race Condition

Published Jan 13, 2026
·
Updated

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid updating compression context during writeback Bai, Shuangpeng <sjb7183@psu.edu> reported a bug as below: Oops: divide error: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 11441 Comm: syz.0.46 Not tainted 6.17.0 #1 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:f2fsallclusterpageready+0x106/0x550 fs/f2fs/compress.c:857 Call Trace: <TASK> f2fswritecachepages fs/f2fs/data.c:3078 [inline] f2fswritedatapages fs/f2fs/data.c:3290 [inline] f2fswritedatapages+0x1c19/0x3600 fs/f2fs/data.c:3317 dowritepages+0x38e/0x640 mm/page-writeback.c:2634 filemapfdatawritewbc mm/filemap.c:386 [inline] filemapfdatawriterange mm/filemap.c:419 [inline] filewriteandwaitrange+0x2ba/0x3e0 mm/filemap.c:794 f2fsdosyncfile+0x6e6/0x1b00 fs/f2fs/file.c:294 genericwritesync include/linux/fs.h:3043 [inline] f2fsfilewriteiter+0x76e/0x2700 fs/f2fs/file.c:5259 newsyncwrite fs/readwrite.c:593 [inline] vfswrite+0x7e9/0xe00 fs/readwrite.c:686 ksyswrite+0x19d/0x2d0 fs/readwrite.c:738 dosyscallx64 arch/x86/entry/syscall64.c:63 [inline] dosyscall64+0xf7/0x470 arch/x86/entry/syscall64.c:94 entrySYSCALL64afterhwframe+0x77/0x7f The bug was triggered w/ below race condition: fsync setattr ioctl - f2fsdosyncfile - filewriteandwaitrange - f2fswritecachepages : inode is non-compressed : cc.clustersize = F2FSI(inode)->iclustersize = 0 - tagpagesforwriteback - f2fssetattr - truncatesetsize - f2fstruncate - f2fsfileattrset - f2fssetflagscommon - setcompresscontext : F2FSI(inode)->iclustersize = 4 : setinodeflag(inode, FICOMPRESSEDFILE) - f2fscompressedfile : return true - f2fsallclusterpageready : "pgidx % cc->clustersize" trigger dividing 0 issue Let's change as below to fix this issue: - introduce a new atomic type variable .writeback in structure f2fsinodeinfo to track the number of threads which calling f2fswritecachepages(). - use .isem lock to protect .writeback update. - check .writeback before update compression context in f2fssetflagscommon() to avoid race w/ ->writepages.

Affected Software

189 affected componentsFixes available
ubuntu/linux-hwe-edge*
ubuntu/linux-aws-5.0*
ubuntu/linux-aws-5.3*
ubuntu/linux-azure*
ubuntu/linux-azure-5.3*
ubuntu/linux-azure-edge*
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.3*
ubuntu/linux-gke-4.15*
ubuntu/linux-gke-5.4*
ubuntu/linux-gkeop-5.4*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-5.11*
ubuntu/linux-aws-5.13*
ubuntu/linux-aws-5.15*
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.15*
ubuntu/linux-azure-5.8*
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-5.15*
ubuntu/linux-gcp-5.11*
ubuntu/linux-gcp-5.13*
ubuntu/linux-gcp-5.15*
ubuntu/linux-gcp-5.8*
ubuntu/linux-gke*
ubuntu/linux-gke-5.15*
ubuntu/linux-gkeop*
ubuntu/linux-gkeop-5.15*
ubuntu/linux-hwe-5.11*
ubuntu/linux-hwe-5.13*
ubuntu/linux-hwe-5.15*
ubuntu/linux-hwe-5.8*
ubuntu/linux-ibm-5.15*
ubuntu/linux-intel-5.13*
ubuntu/linux-intel-iotg-5.15*
ubuntu/linux-lowlatency-hwe-5.15*
ubuntu/linux-nvidia-tegra-5.15*
ubuntu/linux-oem-5.10*
ubuntu/linux-oem-5.13*
ubuntu/linux-oem-5.6*
ubuntu/linux-oracle-5.11*
ubuntu/linux-oracle-5.13*
ubuntu/linux-oracle-5.15*
ubuntu/linux-oracle-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.11*
ubuntu/linux-riscv-5.15*
ubuntu/linux-riscv-5.8*
ubuntu/linux*
ubuntu/linux-allwinner-5.19*
ubuntu/linux-aws*
ubuntu/linux-aws-5.19*
ubuntu/linux-aws-6.2*
ubuntu/linux-aws-6.5*
ubuntu/linux-aws-6.8<6.8.0-1052.55~22.04.1
6.8.0-1052.55~22.04.1
ubuntu/linux-azure*
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-6.8<6.8.0-1059.65~22.04.1
6.8.0-1059.65~22.04.1
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-azure-fde-6.2*
ubuntu/linux-azure-fde-6.8<6.8.0-1058.65~22.04.1
6.8.0-1058.65~22.04.1
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.19*
ubuntu/linux-gcp-6.2*
ubuntu/linux-gcp-6.5*
ubuntu/linux-gcp-6.8<6.8.0-1054.57~22.04.1
6.8.0-1054.57~22.04.1
ubuntu/linux-gke*
ubuntu/linux-gkeop*
ubuntu/linux-hwe-5.19*
ubuntu/linux-hwe-6.2*
ubuntu/linux-hwe-6.5*
ubuntu/linux-hwe-6.8<6.8.0-110.110~22.04.1
6.8.0-110.110~22.04.1
ubuntu/linux-ibm*
ubuntu/linux-ibm-6.8<6.8.0-1051.51~22.04.1
6.8.0-1051.51~22.04.1
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-intel-iotg*
ubuntu/linux-kvm*
ubuntu/linux-lowlatency*
ubuntu/linux-lowlatency-hwe-5.19*
ubuntu/linux-lowlatency-hwe-6.2*
ubuntu/linux-lowlatency-hwe-6.5*
ubuntu/linux-lowlatency-hwe-6.8<6.8.0-110.110.1~22.04.1
6.8.0-110.110.1~22.04.1
ubuntu/linux-nvidia*
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-6.8<6.8.0-1051.54~22.04.1
6.8.0-1051.54~22.04.1
ubuntu/linux-nvidia-tegra*
ubuntu/linux-nvidia-tegra-igx*
ubuntu/linux-oem-5.17*
ubuntu/linux-oem-6.0*
ubuntu/linux-oem-6.1*
ubuntu/linux-oem-6.5*
ubuntu/linux-oracle*
ubuntu/linux-oracle-6.5*
ubuntu/linux-oracle-6.8<6.8.0-1049.50~22.04.1
6.8.0-1049.50~22.04.1
ubuntu/linux-raspi*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-riscv-6.8<6.8.0-110.110~22.04.1
6.8.0-110.110~22.04.1
ubuntu/linux-starfive-5.19*
ubuntu/linux-starfive-6.2*
ubuntu/linux-starfive-6.5*
ubuntu/linux-xilinx-zynqmp*
ubuntu/linux-bluefield*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-realtime-6.8<6.8.1-1047.48~22.04.1
6.8.1-1047.48~22.04.1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<6.8.0-110.110
6.8.0-110.110
ubuntu/linux-aws<6.8.0-1052.55
6.8.0-1052.55
ubuntu/linux-aws-6.14*
ubuntu/linux-aws-6.17<6.17.0-1012.12~24.04.1
6.17.0-1012.12~24.04.1
ubuntu/linux-azure<6.8.0-1054.60
6.8.0-1054.60
ubuntu/linux-azure-6.11*
ubuntu/linux-azure-6.14*
ubuntu/linux-azure-6.17<6.17.0-1013.13~24.04.1
6.17.0-1013.13~24.04.1
ubuntu/linux-azure-fde<6.8.0-1058.65
6.8.0-1058.65
ubuntu/linux-azure-fde-6.14*
ubuntu/linux-azure-nvidia<6.8.0-1039.42
6.8.0-1039.42
ubuntu/linux-azure-nvidia-6.14*
ubuntu/linux-gcp<6.8.0-1054.57
6.8.0-1054.57
ubuntu/linux-gcp-6.11*
ubuntu/linux-gcp-6.14*
ubuntu/linux-gcp-6.17<6.17.0-1012.12~24.04.1
6.17.0-1012.12~24.04.1
ubuntu/linux-gke<6.8.0-1050.56
6.8.0-1050.56
ubuntu/linux-gkeop<6.8.0-1037.40
6.8.0-1037.40
ubuntu/linux-hwe-6.11*
ubuntu/linux-hwe-6.14*
ubuntu/linux-hwe-6.17<6.17.0-22.22~24.04.1
6.17.0-22.22~24.04.1
ubuntu/linux-ibm<6.8.0-1051.51
6.8.0-1051.51
ubuntu/linux-lowlatency<6.8.0-110.110.1
6.8.0-110.110.1
ubuntu/linux-lowlatency-hwe-6.11*
ubuntu/linux-nvidia<6.8.0-1051.54
6.8.0-1051.54
ubuntu/linux-nvidia-6.11*
ubuntu/linux-nvidia-6.17<6.17.0-1018.18
6.17.0-1018.18
ubuntu/linux-nvidia-lowlatency<6.8.0-1051.54.1
6.8.0-1051.54.1
ubuntu/linux-nvidia-tegra<6.8.0-1022.22
6.8.0-1022.22
ubuntu/linux-oem-6.11*
ubuntu/linux-oem-6.14*
ubuntu/linux-oem-6.17<6.17.0-1020.20
6.17.0-1020.20
ubuntu/linux-oem-6.8*
ubuntu/linux-oracle<6.8.0-1049.50
6.8.0-1049.50
ubuntu/linux-oracle-6.14*
ubuntu/linux-oracle-6.17<6.17.0-1011.11~24.04.1
6.17.0-1011.11~24.04.1
ubuntu/linux-raspi<6.8.0-1052.56
6.8.0-1052.56
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-6.14*
ubuntu/linux-riscv-6.17<6.17.0-22.22.1~24.04.1
6.17.0-22.22.1~24.04.1
ubuntu/linux-xilinx<6.8.0-1028.29
6.8.0-1028.29
ubuntu/linux-bluefield<6.8.0-1017.21
6.8.0-1017.21
ubuntu/linux-raspi-realtime<6.8.0-2042.43
6.8.0-2042.43
ubuntu/linux-realtime<6.8.1-1047.48
6.8.1-1047.48
ubuntu/linux-realtime-6.14*
ubuntu/linux-realtime-6.17<6.17.0-1010.11~24.04.1
6.17.0-1010.11~24.04.1
ubuntu/linux-aws-fips<6.8.0-1052.55+fips1
6.8.0-1052.55+fips1
ubuntu/linux-azure-fips<6.8.0-1053.59+fips1
6.8.0-1053.59+fips1
ubuntu/linux-fips<6.8.0-110.110+fips2
6.8.0-110.110+fips2
ubuntu/linux-gcp-fips<6.8.0-1054.57+fips1
6.8.0-1054.57+fips1
ubuntu/linux<6.17.0-22.22
6.17.0-22.22
ubuntu/linux-aws<6.17.0-1012.12
6.17.0-1012.12
ubuntu/linux-azure<6.17.0-1013.13
6.17.0-1013.13
ubuntu/linux-azure-fde*
ubuntu/linux-gcp<6.17.0-1012.12
6.17.0-1012.12
ubuntu/linux-oracle<6.17.0-1011.11
6.17.0-1011.11
ubuntu/linux-raspi<6.17.0-1013.13
6.17.0-1013.13
ubuntu/linux-realtime<6.17.0-1010.11
6.17.0-1010.11
ubuntu/linux-riscv<6.17.0-22.22.1
6.17.0-22.22.1
ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1052.55~22.04.1
  2. Upgrade

    Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1059.65~22.04.1
  3. Upgrade

    Upgrade ubuntu/linux-azure-fde-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1058.65~22.04.1
  4. Upgrade

    Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1054.57~22.04.1
  5. Upgrade

    Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110~22.04.1
  6. Upgrade

    Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.51~22.04.1
  7. Upgrade

    Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110.1~22.04.1
  8. Upgrade

    Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.54~22.04.1
  9. Upgrade

    Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1049.50~22.04.1
  10. Upgrade

    Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110~22.04.1
  11. Upgrade

    Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.1-1047.48~22.04.1
  12. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110
  13. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 6.8.0-1052.55
  14. Upgrade

    Upgrade ubuntu/linux-aws-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1012.12~24.04.1
  15. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 6.8.0-1054.60
  16. Upgrade

    Upgrade ubuntu/linux-azure-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1013.13~24.04.1
  17. Upgrade

    Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.

    Fixed in 6.8.0-1058.65
  18. Upgrade

    Upgrade ubuntu/linux-azure-nvidia to a version that resolves this vulnerability.

    Fixed in 6.8.0-1039.42
  19. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 6.8.0-1054.57
  20. Upgrade

    Upgrade ubuntu/linux-gcp-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1012.12~24.04.1
  21. Upgrade

    Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.

    Fixed in 6.8.0-1050.56
  22. Upgrade

    Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.

    Fixed in 6.8.0-1037.40
  23. Upgrade

    Upgrade ubuntu/linux-hwe-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-22.22~24.04.1
  24. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.51
  25. Upgrade

    Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110.1
  26. Upgrade

    Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.54
  27. Upgrade

    Upgrade ubuntu/linux-nvidia-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1018.18
  28. Upgrade

    Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.54.1
  29. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.

    Fixed in 6.8.0-1022.22
  30. Upgrade

    Upgrade ubuntu/linux-oem-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1020.20
  31. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 6.8.0-1049.50
  32. Upgrade

    Upgrade ubuntu/linux-oracle-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1011.11~24.04.1
  33. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 6.8.0-1052.56
  34. Upgrade

    Upgrade ubuntu/linux-riscv-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-22.22.1~24.04.1
  35. Upgrade

    Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.

    Fixed in 6.8.0-1028.29
  36. Upgrade

    Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.

    Fixed in 6.8.0-1017.21
  37. Upgrade

    Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.

    Fixed in 6.8.0-2042.43
  38. Upgrade

    Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.

    Fixed in 6.8.1-1047.48
  39. Upgrade

    Upgrade ubuntu/linux-realtime-6.17 to a version that resolves this vulnerability.

    Fixed in 6.17.0-1010.11~24.04.1
  40. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1052.55+fips1
  41. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1053.59+fips1
  42. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-110.110+fips2
  43. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1054.57+fips1
  44. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 6.17.0-22.22
  45. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 6.17.0-1012.12
  46. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 6.17.0-1013.13
  47. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 6.17.0-1012.12
  48. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 6.17.0-1011.11
  49. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 6.17.0-1013.13
  50. Upgrade

    Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.

    Fixed in 6.17.0-1010.11
  51. Upgrade

    Upgrade ubuntu/linux-riscv to a version that resolves this vulnerability.

    Fixed in 6.17.0-22.22.1
  52. Compensating control

    In f2fs_setflags_common(), check the f2fs_inode_info .writeback counter before updating the compression context, and protect .writeback updates with the .i_sem lock; introduce an atomic .writeback variable to track threads calling f2fs_write_cache_pages().

Event History

Jan 13, 2026
CVE Published
via OSV·04:15 PM
Data Sourced
via OSV·04:15 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What access does an attacker need to exploit this issue?

The vector is local and requires low privileges. No user interaction is required.

2

What is the expected security impact?

The provided severity vector indicates high availability impact, with no confidentiality or integrity impact. The reported failure is a kernel divide-error Oops during F2FS writeback.

3

How can I identify a potentially related failure?

Look for kernel Oops or divide-error reports during F2FS writeback, with stack frames including f2fs_all_cluster_page_ready, f2fs_write_data_pages, or f2fs_do_sync_file.

Contact

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