Bug 2540436 (CVE-2026-93285)

Summary: CVE-2026-93285 kernel: f2fs: embed f2fs_gc_kthread in f2fs_sb_info
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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
Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the Linux kernel's Flash-Friendly File System (F2FS). A race condition exists during filesystem remount or shutdown operations where background garbage collection tasks are improperly synchronized with teardown routines. A local user could exploit this timing flaw through concurrent filesystem operations, leading to an invalid memory access and a kernel crash that results in a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-09-24 16:48:45 UTC
In the Linux kernel, the following vulnerability has been resolved:

f2fs: embed f2fs_gc_kthread in f2fs_sb_info

Instead of allocating f2fs_gc_kthread dynamically, embed it in
f2fs_sb_info. This simplifies lifetime management and prepares for
fixing race conditions during teardown.

- __sbi_store			- remount|shutdown
				 - f2fs_stop_gc_thread
 - access sbi->gc_thread
				  - sbi->gc_thread = NULL
 - access sbi->gc_thread->f2fs_gc_task