kernel: erofs: disable LZ4 rolling decompression for now

cve CVE-2026-98067 3 sources, 4 claims · Watch

Red Hat writes:
kernel: erofs: disable LZ4 rolling decompression for now the claim

Severity they disagree: unknown GitHub advisories
low Red Hat
CVSS: 5.5 Red Hat
Vendor: Linux NVD
Product: Linux NVD
CWE: CWE-440 Red Hat

How far exploitation has got

No public code known
Proof of concept
Proof of concept, verified
A Metasploit module
Exploited in the wild
Used in ransomware campaigns

Timeline

2026-09-25	first spoke of it: In the Linux kernel, the following vulnerability has been resolved: erofs: disable LZ4 rolling...	GitHub advisories
2026-09-25	first spoke of it: In the Linux kernel, the following vulnerability has been resolved: erofs: disable LZ4 rolling decompression for now LZ4 rolling decompression [1] was introduced to reduce the memory footprint of temporary pages: For many cases, it is needed for users to read small data within a compressed extent (pcluster), either due to random small read, or since uptodate folios (typically order-0) cannot be reused for decompression again since decompression algorithm refills already-uptodate folios. Rolling decompression works because LZ4 is LZ77-based and only refers to the most recent 64 KiB of decompressed data, so in theory only a bounded rolling window of temporary pages is needed when decompressing. It can save a lot of temporary memory, e.g. 601,960-byte data can be compressed into a 256k LZ4 compressed extent, which means it needs 146 extra pages per request in the worst case if rolling decompression is disabled. However, the upstream LZ4 implementation is not under EROFS' control: For example, the literal copy memmove() may still copy long literals backward on x86 based on the address comparison even when the source and destination ranges do not overlap (IOWs, inline decompression doesn't need to be considered here). That breaks the rolling assumption and makes the optimization broken. Disable it for now to make sure the data correctness first since EROFS is used everywhere now: The rolling window approach can be revived once we either ensure that the official LZ4 code always copies forward for non-overlapping ranges or maintain our own LZ4 implementation in EROFS. The main impact is a higher runtime memory footprint; However, recent commit 0f6273ab4637 ("erofs: add a reserved buffer pool for lz4 decompression") helps mitigate this when enabled but it's still not perfect. [1] https://www.usenix.org/conference/atc19/presentation/gao § 3.3 Decompression	NVD
2026-09-25	first spoke of it: kernel: erofs: disable LZ4 rolling decompression for now	Red Hat

What it is to other things

In words only, so not counted until a person confirms one:

affects	`linux/linux` NVD says “Linux · Linux”
made_by	`linux` NVD says “Linux”

Every value, with what each source said and its receipt

Property Source Said Means here

CVSS

cvss

Red Hat

5.5

receipt

Source: Red Hat
Its words: 5.5
Read by: field:cvss3_score
Said since: 2026-10-06 13:01 UTC
Last answered: 2026-10-06 13:02 UTC
Original: open at the source

What the source handed over

{
  "CVE": "CVE-2026-98067",
  "CWE": "CWE-440",
  "advisories": [],
  "affected_packages": [],
  "bugzilla": "2541261",
  "bugzilla_description": "kernel: erofs: disable LZ4 rolling decompression for now",
  "cvss3_score": "5.5",
  "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2026-09-25T00:00:00Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-98067.json",
  "severity": "low"
}

—

CVSS vector

cvss_vector

Red Hat

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

receipt

Source: Red Hat
Its words: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Read by: field:cvss3_scoring_vector
Said since: 2026-10-06 13:01 UTC
Last answered: 2026-10-06 13:02 UTC
Original: open at the source

What the source handed over

{
  "CVE": "CVE-2026-98067",
  "CWE": "CWE-440",
  "advisories": [],
  "affected_packages": [],
  "bugzilla": "2541261",
  "bugzilla_description": "kernel: erofs: disable LZ4 rolling decompression for now",
  "cvss3_score": "5.5",
  "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2026-09-25T00:00:00Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-98067.json",
  "severity": "low"
}

—

CWE

cwe

Red Hat

CWE-440

receipt

Source: Red Hat
Its words: CWE-440
Read by: field:CWE
Said since: 2026-10-06 13:01 UTC
Last answered: 2026-10-06 13:02 UTC
Original: open at the source

What the source handed over

{
  "CVE": "CVE-2026-98067",
  "CWE": "CWE-440",
  "advisories": [],
  "affected_packages": [],
  "bugzilla": "2541261",
  "bugzilla_description": "kernel: erofs: disable LZ4 rolling decompression for now",
  "cvss3_score": "5.5",
  "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2026-09-25T00:00:00Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-98067.json",
  "severity": "low"
}

—

Product

product

NVD

Linux

receipt

Source: NVD
Its words: Linux
Read by: field:cve.affected[].affectedData[].product
Said since: 2026-09-29 17:49 UTC
Last answered: 2026-10-06 12:41 UTC
Original: open at the source

2026-09-29 17:49 UTC	Linux
2026-09-29 09:45 UTC	—

What the source handed over

{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "fs/erofs/decompressor.c",
              "fs/erofs/internal.h",
              "fs/erofs/zdata.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              },
              {
                "lessThan": "c9a2db4b9950b59c571258e4bae74c271f62dd66",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              },
              {
                "lessThan": "82e664cf1219c459c33aae931b222cf951af9cb7",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "fs/erofs/decompressor.c",
              "fs/erofs/internal.h",
              "fs/erofs/zdata.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "5.13"
              },
              {
                "lessThan": "5.13",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.18.*",
                "status": "unaffected",
                "version": "6.18.53",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "7.2.*",
                "status": "unaffected",
                "version": "7.2.7",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "7.3-rc3",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: disable LZ4 rolling decompression for now\n\nLZ4 rolling decompression [1] was introduced to reduce the memory\nfootprint of temporary pages:\n\n For many cases, it is needed for users to read small data within\n a compressed extent (pcluster), either due to random small read, or\n since uptodate folios (typically order-0) cannot be reused for\n decompression again since decompression algorithm refills\n already-uptodate folios.\n\nRolling decompression works because LZ4 is LZ77-based and only refers\nto the most recent 64 KiB of decompressed data, so in theory only a\nbounded rolling window of temporary pages is needed when decompressing.\n\nIt can save a lot of temporary memory, e.g.\n 601,960-byte data can be compressed into a 256k LZ4 compressed extent,\n which means it needs 146 extra pages per request in the worst case if\n rolling decompression is disabled.\n\nHowever, the upstream LZ4 implementation is not under EROFS' control:\nFor example, the literal copy memmove() may still **copy long literals\nbackward** on x86 based on the address comparison even when the source\nand destination ranges do not overlap (IOWs, inline decompression\ndoesn't need to be considered here). That breaks the rolling assumption\nand makes the optimization broken.\n\nDisable it for now to make sure the data correctness first since EROFS\nis used everywhere now: The rolling window approach can be revived once\nwe either ensure that the official LZ4 code always copies forward for\nnon-overlapping ranges or maintain our own LZ4 implementation in EROFS.\n\nThe main impact is a higher runtime memory footprint; However, recent\ncommit 0f6273ab4637 (\"erofs: add a reserved buffer pool for lz4\ndecompression\") helps mitigate this when enabled but it's still not\nperfect.\n\n[1] https://www.usenix.org/conference/atc19/presentation/gao\n    § 3.3 Decompression"
      }
    ],
    "id": "CVE-2026-98067",
    "lastModified": "2026-09-30T14:10:59.253",
    "metrics": {},
    "published": "2026-09-25T11:17:35.787",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/82e664cf1219c459c33aae931b222cf951af9cb7"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/c9a2db4b9950b59c571258e4bae74c271f62dd66"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Undergoing Analysis"
  }
}

—

Severity

severity

conflict

GitHub advisories

unknown

receipt

Source: GitHub advisories
Said since: 2026-09-26 15:00 UTC
Last answered: 2026-10-06 13:46 UTC
Original: open at the source

This source has not kept a receipt for this claim yet. The next update that reads it will.

—

Severity

severity

conflict

Red Hat

low

A flaw that is unlikely to be exploited, or whose impact is minimal.

receipt

Source: Red Hat
Its words: low
Read by: field:severity
Said since: 2026-10-06 13:01 UTC
Last answered: 2026-10-06 13:02 UTC
Original: open at the source

What the source handed over

{
  "CVE": "CVE-2026-98067",
  "CWE": "CWE-440",
  "advisories": [],
  "affected_packages": [],
  "bugzilla": "2541261",
  "bugzilla_description": "kernel: erofs: disable LZ4 rolling decompression for now",
  "cvss3_score": "5.5",
  "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "cvss_score": null,
  "cvss_scoring_vector": null,
  "package_state": null,
  "public_date": "2026-09-25T00:00:00Z",
  "resource_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-98067.json",
  "severity": "low"
}

—

Status

status

NVD

Undergoing Analysis

receipt

Source: NVD
Its words: Undergoing Analysis
Read by: field:cve.vulnStatus
Said since: 2026-10-06 11:32 UTC
Last answered: 2026-10-06 12:41 UTC
Original: open at the source

2026-10-06 11:32 UTC	Undergoing Analysis
2026-10-02 12:00 UTC	Awaiting Analysis
2026-09-29 09:45 UTC	Received

What the source handed over

{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "fs/erofs/decompressor.c",
              "fs/erofs/internal.h",
              "fs/erofs/zdata.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              },
              {
                "lessThan": "c9a2db4b9950b59c571258e4bae74c271f62dd66",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              },
              {
                "lessThan": "82e664cf1219c459c33aae931b222cf951af9cb7",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "fs/erofs/decompressor.c",
              "fs/erofs/internal.h",
              "fs/erofs/zdata.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "5.13"
              },
              {
                "lessThan": "5.13",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.18.*",
                "status": "unaffected",
                "version": "6.18.53",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "7.2.*",
                "status": "unaffected",
                "version": "7.2.7",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "7.3-rc3",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: disable LZ4 rolling decompression for now\n\nLZ4 rolling decompression [1] was introduced to reduce the memory\nfootprint of temporary pages:\n\n For many cases, it is needed for users to read small data within\n a compressed extent (pcluster), either due to random small read, or\n since uptodate folios (typically order-0) cannot be reused for\n decompression again since decompression algorithm refills\n already-uptodate folios.\n\nRolling decompression works because LZ4 is LZ77-based and only refers\nto the most recent 64 KiB of decompressed data, so in theory only a\nbounded rolling window of temporary pages is needed when decompressing.\n\nIt can save a lot of temporary memory, e.g.\n 601,960-byte data can be compressed into a 256k LZ4 compressed extent,\n which means it needs 146 extra pages per request in the worst case if\n rolling decompression is disabled.\n\nHowever, the upstream LZ4 implementation is not under EROFS' control:\nFor example, the literal copy memmove() may still **copy long literals\nbackward** on x86 based on the address comparison even when the source\nand destination ranges do not overlap (IOWs, inline decompression\ndoesn't need to be considered here). That breaks the rolling assumption\nand makes the optimization broken.\n\nDisable it for now to make sure the data correctness first since EROFS\nis used everywhere now: The rolling window approach can be revived once\nwe either ensure that the official LZ4 code always copies forward for\nnon-overlapping ranges or maintain our own LZ4 implementation in EROFS.\n\nThe main impact is a higher runtime memory footprint; However, recent\ncommit 0f6273ab4637 (\"erofs: add a reserved buffer pool for lz4\ndecompression\") helps mitigate this when enabled but it's still not\nperfect.\n\n[1] https://www.usenix.org/conference/atc19/presentation/gao\n    § 3.3 Decompression"
      }
    ],
    "id": "CVE-2026-98067",
    "lastModified": "2026-09-30T14:10:59.253",
    "metrics": {},
    "published": "2026-09-25T11:17:35.787",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/82e664cf1219c459c33aae931b222cf951af9cb7"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/c9a2db4b9950b59c571258e4bae74c271f62dd66"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Undergoing Analysis"
  }
}

—

Vendor

vendor

NVD

Linux

receipt

Source: NVD
Its words: Linux
Read by: field:cve.affected[].affectedData[].vendor
Said since: 2026-09-29 17:49 UTC
Last answered: 2026-10-06 12:41 UTC
Original: open at the source

2026-09-29 17:49 UTC	Linux
2026-09-29 09:45 UTC	—

What the source handed over

{
  "cve": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "fs/erofs/decompressor.c",
              "fs/erofs/internal.h",
              "fs/erofs/zdata.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              },
              {
                "lessThan": "c9a2db4b9950b59c571258e4bae74c271f62dd66",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              },
              {
                "lessThan": "82e664cf1219c459c33aae931b222cf951af9cb7",
                "status": "affected",
                "version": "8e6c8fa9f2e95c88a642521a5da19a8e31748846",
                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "fs/erofs/decompressor.c",
              "fs/erofs/internal.h",
              "fs/erofs/zdata.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "5.13"
              },
              {
                "lessThan": "5.13",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.18.*",
                "status": "unaffected",
                "version": "6.18.53",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "7.2.*",
                "status": "unaffected",
                "version": "7.2.7",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "7.3-rc3",
                "versionType": "original_commit_for_fix"
              }
            ]
          }
        ],
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
      }
    ],
    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: disable LZ4 rolling decompression for now\n\nLZ4 rolling decompression [1] was introduced to reduce the memory\nfootprint of temporary pages:\n\n For many cases, it is needed for users to read small data within\n a compressed extent (pcluster), either due to random small read, or\n since uptodate folios (typically order-0) cannot be reused for\n decompression again since decompression algorithm refills\n already-uptodate folios.\n\nRolling decompression works because LZ4 is LZ77-based and only refers\nto the most recent 64 KiB of decompressed data, so in theory only a\nbounded rolling window of temporary pages is needed when decompressing.\n\nIt can save a lot of temporary memory, e.g.\n 601,960-byte data can be compressed into a 256k LZ4 compressed extent,\n which means it needs 146 extra pages per request in the worst case if\n rolling decompression is disabled.\n\nHowever, the upstream LZ4 implementation is not under EROFS' control:\nFor example, the literal copy memmove() may still **copy long literals\nbackward** on x86 based on the address comparison even when the source\nand destination ranges do not overlap (IOWs, inline decompression\ndoesn't need to be considered here). That breaks the rolling assumption\nand makes the optimization broken.\n\nDisable it for now to make sure the data correctness first since EROFS\nis used everywhere now: The rolling window approach can be revived once\nwe either ensure that the official LZ4 code always copies forward for\nnon-overlapping ranges or maintain our own LZ4 implementation in EROFS.\n\nThe main impact is a higher runtime memory footprint; However, recent\ncommit 0f6273ab4637 (\"erofs: add a reserved buffer pool for lz4\ndecompression\") helps mitigate this when enabled but it's still not\nperfect.\n\n[1] https://www.usenix.org/conference/atc19/presentation/gao\n    § 3.3 Decompression"
      }
    ],
    "id": "CVE-2026-98067",
    "lastModified": "2026-09-30T14:10:59.253",
    "metrics": {},
    "published": "2026-09-25T11:17:35.787",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/82e664cf1219c459c33aae931b222cf951af9cb7"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/c9a2db4b9950b59c571258e4bae74c271f62dd66"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/ec52dfed7b14514ed97ee71161e4cf4cfe2fbff2"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Undergoing Analysis"
  }
}

—

Every claim, by kind

vulnerability

kernel: erofs: disable LZ4 rolling decompression for now zetlyn/cve-redhat · 2026-09-25	cvss 5.5 cvss_vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H cwe CWE-440 severity low	source
In the Linux kernel, the following vulnerability has been resolved: erofs: disable LZ4 rolling decompression for now LZ4 rolling decompression [1] was introduced to reduce the memory footprint of temporary pages: For many cases, it is needed for users to read small data within a compressed extent (pcluster), either due to random small read, or since uptodate folios (typically order-0) cannot be reused for decompression again since decompression algorithm refills already-uptodate folios. Rolling decompression works because LZ4 is LZ77-based and only refers to the most recent 64 KiB of decompressed data, so in theory only a bounded rolling window of temporary pages is needed when decompressing. It can save a lot of temporary memory, e.g. 601,960-byte data can be compressed into a 256k LZ4 compressed extent, which means it needs 146 extra pages per request in the worst case if rolling decompression is disabled. However, the upstream LZ4 implementation is not under EROFS' control: For example, the literal copy memmove() may still copy long literals backward on x86 based on the address comparison even when the source and destination ranges do not overlap (IOWs, inline decompression doesn't need to be considered here). That breaks the rolling assumption and makes the optimization broken. Disable it for now to make sure the data correctness first since EROFS is used everywhere now: The rolling window approach can be revived once we either ensure that the official LZ4 code always copies forward for non-overlapping ranges or maintain our own LZ4 implementation in EROFS. The main impact is a higher runtime memory footprint; However, recent commit 0f6273ab4637 ("erofs: add a reserved buffer pool for lz4 decompression") helps mitigate this when enabled but it's still not perfect. [1] https://www.usenix.org/conference/atc19/presentation/gao § 3.3 Decompression zetlyn/cve-nvd · 2026-09-25	product Linux status Undergoing Analysis vendor Linux	source
In the Linux kernel, the following vulnerability has been resolved: erofs: disable LZ4 rolling... zetlyn/cve-ghsa · 2026-09-25	severity unknown	source
In the Linux kernel, the following vulnerability has been resolved: erofs: disable LZ4 rolling... zetlyn/cve-ghsa · 2026-09-25	severity unknown	source