Bug 2516280 (CVE-2026-72160)
| Summary: | CVE-2026-72160 kernel: ocfs2: reject dinodes with non-canonical i_mode type | ||
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| Product: | [Other] Security Response | Reporter: | OSIDB Bzimport <bzimport> |
| Component: | vulnerability | Assignee: | Product Security DevOps Team <prodsec-dev> |
| Status: | NEW --- | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | unspecified | CC: | rhel-process-autobot, watson-tool-maintainers |
| Target Milestone: | --- | Keywords: | Security |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | --- | |
| Doc Text: |
A flaw was found in ocfs2 (Oracle Cluster File System version 2) in the Linux kernel. This vulnerability arises from insufficient validation of on-disk inode metadata, specifically the `i_mode` type bits. A local attacker could exploit this by crafting a malformed disk inode with a non-canonical POSIX file type. This could bypass existing validation checks, potentially leading to unexpected system behavior or instability when the kernel processes the malformed inode.
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Story Points: | --- |
| Clone Of: | Environment: | ||
| Last Closed: | Type: | --- | |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
In the Linux kernel, the following vulnerability has been resolved: ocfs2: reject dinodes with non-canonical i_mode type Patch series "ocfs2: harden inode validators against forged metadata", v2. This series adds three structural checks to OCFS2 dinode validation so malformed on-disk fields are rejected before ocfs2_populate_inode() copies them into the in-core inode. The checks cover: - i_mode values whose type bits do not name a canonical POSIX file type; - non-device dinodes whose id1.dev1.i_rdev field is non-zero; and - non-inline dinodes that claim non-zero i_size while i_clusters is zero, covering directories unconditionally and regular files on non-sparse volumes. The normal read path reports these through ocfs2_error(), matching the existing suballoc-slot, inline-data, chain-list, and refcount checks. The online filecheck path uses the same structural predicates but keeps its own reporting contract, returning OCFS2_FILECHECK_ERR_INVALIDINO instead of calling ocfs2_error(). This patch (of 3): ocfs2_validate_inode_block() currently accepts any non-zero i_mode value. ocfs2_populate_inode() then copies that mode verbatim into inode->i_mode and dispatches on i_mode & S_IFMT to the file/dir/symlink/special_file iops; an unrecognised type falls through to ocfs2_special_file_iops and init_special_inode(). Reject dinodes whose type bits do not name one of the seven canonical POSIX file types. Use fs_umode_to_ftype(), the same generic file-type conversion helper OCFS2 already uses for directory entries, so the accepted inode type set matches the kernel file-type vocabulary instead of open-coding a local switch. Apply the same structural check to the online filecheck read path. filecheck keeps its own error namespace, so it reports malformed i_mode through the filecheck logger and OCFS2_FILECHECK_ERR_INVALIDINO instead of calling ocfs2_error(), but it must not allow a malformed dinode to proceed into ocfs2_populate_inode().