CVE-2026-89830 (GCVE-0-2026-89830)

Vulnerability from cvelistv5 – Published: 2026-09-16 10:31 – Updated: 2026-10-19 08:53
VLAI
Title
f2fs: fix valid block count leak on data block allocation failure
Summary
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix valid block count leak on data block allocation failure In __allocate_data_block(), when allocating a new data block (dn->data_blkaddr == NULL_ADDR), inc_valid_block_count() is called first to increment total_valid_block_count and i_blocks. If the subsequent f2fs_allocate_data_block() fails, the function returns the error directly without rolling back the already-incremented block counts, causing a permanent leak. Fix this by calling dec_valid_block_count() to undo the increment before returning the error. The condition old_blkaddr == NULL_ADDR precisely identifies the case where inc_valid_block_count() was called.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6639 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47 , < 2d50b6d47e5671ff6a25834c5906d443356191f0 (git)
Affected: 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47 , < dde99df5a9d3b0ca6ac0a86f98799685f7399432 (git)
Affected: 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47 , < 931e1aa4d44c52ff8e0feb38420a8827c62e886b (git)
Affected: 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47 , < 0f9af07ecc1ab486038373db6ae0436c5d674b19 (git)
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Linux Linux Affected: 6.9
Unaffected: 0 , < 6.9 (semver)
Unaffected: 6.12.110 , ≤ 6.12.* (semver)
Unaffected: 6.18.51 , ≤ 6.18.* (semver)
Unaffected: 7.2.5 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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{
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    "dateReserved": "2026-09-11T19:38:34.769Z",
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix valid block count leak on data block allocation failure\n\nIn __allocate_data_block(), when allocating a new data block\n(dn-\u003edata_blkaddr == NULL_ADDR), inc_valid_block_count() is\ncalled first to increment total_valid_block_count and i_blocks.\nIf the subsequent f2fs_allocate_data_block() fails, the function\nreturns the error directly without rolling back the\nalready-incremented block counts, causing a permanent leak.\n\nFix this by calling dec_valid_block_count() to undo the\nincrement before returning the error. The condition\nold_blkaddr == NULL_ADDR precisely identifies the case where\ninc_valid_block_count() was called."
          }
        ],
        "id": "CVE-2026-89830",
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        "metrics": {},
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}



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