CVE-2026-63820
f2fs: fix missing read bio submission on large folio error
Description
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix missing read bio submission on large folio error f2fs_read_data_large_folio() can keep a read bio across multiple readahead folios. If a later folio hits an error before any of its blocks are added to the bio, folio_in_bio is false and the current error path returns immediately after ending that folio. This can leave the bio accumulated for earlier folios unsubmitted. Those folios then never receive read completion, and readers can wait indefinitely on the locked folios. Route errors through the common out path so any pending bio is submitted before returning. Stop consuming more readahead folios once an error is seen, and only wait on and clear the current folio when it was actually added to the bio.
INFO
Published Date :
July 19, 2026, 12:16 p.m.
Last Modified :
July 19, 2026, 12:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-63820
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Route errors through the common out path.
- Stop consuming readahead folios on error.
- Wait on and clear folio only if added to bio.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-63820.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/48c92559e7b66fdc3cbc74f6e152e66ec0150a0a | |
| https://git.kernel.org/stable/c/74c8d2ec95c59a5651ecd975c466998af1961fd4 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-63820 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-63820
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-63820 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-63820 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 19, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'a5d8b9d94e1863f3ebb7182c238b2c713f6f4efd', 'lessThan': '48c92559e7b66fdc3cbc74f6e152e66ec0150a0a', 'versionType': 'git'}, {'status': 'affected', 'version': 'a5d8b9d94e1863f3ebb7182c238b2c713f6f4efd', 'lessThan': '74c8d2ec95c59a5651ecd975c466998af1961fd4', 'versionType': 'git'}], 'programFiles': ['fs/f2fs/data.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '7.0'}, {'status': 'unaffected', 'version': '0', 'lessThan': '7.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.1.3', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/f2fs/data.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: f2fs: fix missing read bio submission on large folio error f2fs_read_data_large_folio() can keep a read bio across multiple readahead folios. If a later folio hits an error before any of its blocks are added to the bio, folio_in_bio is false and the current error path returns immediately after ending that folio. This can leave the bio accumulated for earlier folios unsubmitted. Those folios then never receive read completion, and readers can wait indefinitely on the locked folios. Route errors through the common out path so any pending bio is submitted before returning. Stop consuming more readahead folios once an error is seen, and only wait on and clear the current folio when it was actually added to the bio. Added Reference https://git.kernel.org/stable/c/48c92559e7b66fdc3cbc74f6e152e66ec0150a0a Added Reference https://git.kernel.org/stable/c/74c8d2ec95c59a5651ecd975c466998af1961fd4