Bug 2535251 (CVE-2026-89837)

Summary: CVE-2026-89837 kernel: f2fs: fix dentry folio leak in find_in_level
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's f2fs filesystem. The `find_in_level` function, responsible for managing file system entries, fails to release a memory reference (dentry folio) when an internal error occurs during a call to `find_in_block()`. This oversight leads to a memory leak, which can be exploited by a local attacker to cause resource exhaustion and potentially a Denial of Service (DoS) condition, making the system unresponsive.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-16 11:39:15 UTC 
In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix dentry folio leak in find_in_level

find_in_level() gets a dentry folio with f2fs_find_data_folio() before
calling find_in_block().  If find_in_block() returns an error, the
function stores the error in res_folio and breaks out of the loop without
dropping the dentry folio.

This leaks the folio reference on the find_in_block() error path.  Drop
the dentry folio before returning the error to the caller.
Comment 1 Mauro Matteo Cascella 2026-09-21 18:29:17 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89837.mbox