Bug 2365289 (CVE-2025-37863)

Summary: CVE-2025-37863 kernel: ovl: don't allow datadir only
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: medium    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
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Hardware: All   
OS: Linux   
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Description OSIDB Bzimport 2025-05-09 07:03:32 UTC 
In the Linux kernel, the following vulnerability has been resolved:

ovl: don't allow datadir only

In theory overlayfs could support upper layer directly referring to a data
layer, but there's no current use case for this.

Originally, when data-only layers were introduced, this wasn't allowed,
only introduced by the "datadir+" feature, but without actually handling
this case, resulting in an Oops.

Fix by disallowing datadir without lowerdir.
Comment 1 Michal Findra 2025-05-09 07:31:30 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025050956-CVE-2025-37863-dcf9@gregkh/T