CVE-2023-53186: skbuff: Fix a race between coalescing and releasing SKBs

Published Sep 15, 2025
·
Updated

In the Linux kernel, the following vulnerability has been resolved:

skbuff: Fix a race between coalescing and releasing SKBs

Commit 1effe8ca4e34 ("skbuff: fix coalescing for pagepool fragment recycling") allowed coalescing to proceed with non page pool page and page pool page when @from is cloned, i.e.

to->pprecycle --> false from->pprecycle --> true skbcloned(from) --> true

However, it actually requires skbcloned(@from) to hold true until coalescing finishes in this situation. If the other cloned SKB is released while the merging is in process, fromshinfo->nrfrags will be set to 0 toward the end of the function, causing the increment of frag page refcount to be unexpectedly skipped resulting in inconsistent reference counts. Later when SKB(@to) is released, it frees the page directly even though the page pool page is still in use, leading to use-after-free or double-free errors. So it should be prohibited.

The double-free error message below prompted us to investigate: BUG: Bad page state in process swapper/1 pfn:0e0d1 page:00000000c6548b28 refcount:-1 mapcount:0 mapping:0000000000000000 index:0x2 pfn:0xe0d1 flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff) raw: 000fffffc0000000 0000000000000000 ffffffff00000101 0000000000000000 raw: 0000000000000002 0000000000000000 ffffffffffffffff 0000000000000000 page dumped because: nonzero refcount

CPU: 1 PID: 0 Comm: swapper/1 Tainted: G E 6.2.0+ Call Trace: <IRQ> dumpstacklvl+0x32/0x50 badpage+0x69/0xf0 freepcpprepare+0x260/0x2f0 freeunrefpage+0x20/0x1c0 skbreleasedata+0x10b/0x1a0 napiconsumeskb+0x56/0x150 netrxaction+0xf0/0x350 ? napischedule+0x79/0x90 dosoftirq+0xc8/0x2b1 irqexitrcu+0xb9/0xf0 commoninterrupt+0x82/0xa0 </IRQ> <TASK> asmcommoninterrupt+0x22/0x40 RIP: 0010:defaultidle+0xb/0x20

Affected Software

129 affected componentsFixes available
Linux Linux kernel
Linux Linux kernel>=5.15<5.15.108
Linux Linux kernel>=5.16<6.1.25
Linux Linux kernel>=6.2<6.2.12
Linux Linux kernel=6.3-rc1
Linux Linux kernel=6.3-rc2
Linux Linux kernel=6.3-rc3
Linux Linux kernel=6.3-rc4
Linux Linux kernel=6.3-rc5
Linux Linux kernel=6.3-rc6
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-5.15<5.15.0-1041.46~20.04.1
5.15.0-1041.46~20.04.1
ubuntu/linux-azure-5.15<5.15.0-1045.52~20.04.1
5.15.0-1045.52~20.04.1
ubuntu/linux-gcp-5.15<5.15.0-1039.47~20.04.1
5.15.0-1039.47~20.04.1
ubuntu/linux-hwe-5.15<5.15.0-79.86~20.04.2
5.15.0-79.86~20.04.2
ubuntu/linux-ibm-5.15<5.15.0-1036.39~20.04.1
5.15.0-1036.39~20.04.1
ubuntu/linux-intel-iotg-5.15<5.15.0-1037.42~20.04.1
5.15.0-1037.42~20.04.1
ubuntu/linux-lowlatency-hwe-5.15<5.15.0-79.88~20.04.1
5.15.0-79.88~20.04.1
ubuntu/linux-nvidia-tegra-5.15<5.15.0-1016.16~20.04.1
5.15.0-1016.16~20.04.1
ubuntu/linux-oracle-5.15<5.15.0-1040.46~20.04.1
5.15.0-1040.46~20.04.1
ubuntu/linux-riscv-5.15<5.15.0-1038.42~20.04.2
5.15.0-1038.42~20.04.2
ubuntu/linux-aws-5.11*
ubuntu/linux-aws-5.13*
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.8*
ubuntu/linux-azure-fde*
ubuntu/linux-gcp-5.11*
ubuntu/linux-gcp-5.13*
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-5.8*
ubuntu/linux-intel-5.13*
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-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.11*
ubuntu/linux-riscv-5.8*
ubuntu/linux<5.15.0-79.86
5.15.0-79.86
ubuntu/linux-allwinner-5.19*
ubuntu/linux-aws<5.15.0-1042.47
5.15.0-1042.47
ubuntu/linux-aws-5.19*
ubuntu/linux-aws-6.2*
ubuntu/linux-aws-6.5*
ubuntu/linux-azure<5.15.0-1045.52
5.15.0-1045.52
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-fde<5.15.0-1045.52.1
5.15.0-1045.52.1
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-azure-fde-6.2*
ubuntu/linux-gcp<5.15.0-1039.47
5.15.0-1039.47
ubuntu/linux-gcp-5.19*
ubuntu/linux-gcp-6.2*
ubuntu/linux-gcp-6.5*
ubuntu/linux-gke<5.15.0-1039.44
5.15.0-1039.44
ubuntu/linux-gkeop<5.15.0-1025.30
5.15.0-1025.30
ubuntu/linux-hwe-5.19*
ubuntu/linux-hwe-6.2*
ubuntu/linux-hwe-6.5*
ubuntu/linux-ibm<5.15.0-1035.38
5.15.0-1035.38
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-intel-iotg<5.15.0-1037.42
5.15.0-1037.42
ubuntu/linux-kvm<5.15.0-1039.44
5.15.0-1039.44
ubuntu/linux-lowlatency<5.15.0-79.88
5.15.0-79.88
ubuntu/linux-lowlatency-hwe-5.19*
ubuntu/linux-lowlatency-hwe-6.2*
ubuntu/linux-lowlatency-hwe-6.5*
ubuntu/linux-nvidia<5.15.0-1030.30
5.15.0-1030.30
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-tegra<5.15.0-1016.16
5.15.0-1016.16
ubuntu/linux-nvidia-tegra-igx<5.15.0-1002.2
5.15.0-1002.2
ubuntu/linux-oem-5.17*
ubuntu/linux-oem-6.0*
ubuntu/linux-oem-6.1*
ubuntu/linux-oem-6.5*
ubuntu/linux-oracle<5.15.0-1040.46
5.15.0-1040.46
ubuntu/linux-oracle-6.5*
ubuntu/linux-raspi<5.15.0-1035.38
5.15.0-1035.38
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-starfive-5.19*
ubuntu/linux-starfive-6.2*
ubuntu/linux-starfive-6.5*
ubuntu/linux-xilinx-zynqmp<5.15.0-1025.29
5.15.0-1025.29
ubuntu/linux-bluefield<5.15.0-1022.24
5.15.0-1022.24
ubuntu/linux-intel-iot-realtime<5.15.0-1036.38
5.15.0-1036.38
ubuntu/linux-realtime<5.15.0-1043.48
5.15.0-1043.48
ubuntu/linux-fips*
ubuntu/linux-azure-6.11*
ubuntu/linux-gcp-6.11*
ubuntu/linux-hwe-6.11*
ubuntu/linux-intel*
ubuntu/linux-lowlatency-hwe-6.11*
ubuntu/linux-oem-6.11*
ubuntu/linux-oem-6.8*
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1041.46~20.04.1
  2. Upgrade

    Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1045.52~20.04.1
  3. Upgrade

    Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1039.47~20.04.1
  4. Upgrade

    Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-79.86~20.04.2
  5. Upgrade

    Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1036.39~20.04.1
  6. Upgrade

    Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1037.42~20.04.1
  7. Upgrade

    Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-79.88~20.04.1
  8. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1016.16~20.04.1
  9. Upgrade

    Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1040.46~20.04.1
  10. Upgrade

    Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1038.42~20.04.2
  11. Upgrade

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

    Fixed in 5.15.0-79.86
  12. Upgrade

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

    Fixed in 5.15.0-1042.47
  13. Upgrade

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

    Fixed in 5.15.0-1045.52
  14. Upgrade

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

    Fixed in 5.15.0-1045.52.1
  15. Upgrade

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

    Fixed in 5.15.0-1039.47
  16. Upgrade

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

    Fixed in 5.15.0-1039.44
  17. Upgrade

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

    Fixed in 5.15.0-1025.30
  18. Upgrade

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

    Fixed in 5.15.0-1035.38
  19. Upgrade

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

    Fixed in 5.15.0-1037.42
  20. Upgrade

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

    Fixed in 5.15.0-1039.44
  21. Upgrade

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

    Fixed in 5.15.0-79.88
  22. Upgrade

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

    Fixed in 5.15.0-1030.30
  23. Upgrade

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

    Fixed in 5.15.0-1016.16
  24. Upgrade

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

    Fixed in 5.15.0-1002.2
  25. Upgrade

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

    Fixed in 5.15.0-1040.46
  26. Upgrade

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

    Fixed in 5.15.0-1035.38
  27. Upgrade

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

    Fixed in 5.15.0-1025.29
  28. Upgrade

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

    Fixed in 5.15.0-1022.24
  29. Upgrade

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

    Fixed in 5.15.0-1036.38
  30. Upgrade

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

    Fixed in 5.15.0-1043.48

Event History

Sep 15, 2025
CVE Published
via MITRE·02:04 PM
Data Sourced
via MITRE·02:04 PM
DescriptionSeverity
Data Sourced
via OSV·02:15 PM
DescriptionSeverityAffected Software
Event
via OSV·02:15 PM
Data Sourced
via NVD·02:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Data Sourced
via Red Hat·03:03 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2023-53186?

CVE-2023-53186 has been classified as a medium severity vulnerability.

2

How do I fix CVE-2023-53186?

To fix CVE-2023-53186, update your Linux kernel to the latest patched version provided by your distribution.

3

What are the implications of CVE-2023-53186?

CVE-2023-53186 can lead to instability in network operations due to a race condition affecting skbuff handling.

4

Which versions of Linux Kernel are affected by CVE-2023-53186?

CVE-2023-53186 affects various versions of the Linux Kernel prior to the fix implemented in later releases.

5

Is CVE-2023-53186 related to any specific Linux distributions?

CVE-2023-53186 impacts all Linux distributions utilizing the affected versions of the Linux Kernel.

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