AZL-92600
See a problem?- Import Source
- https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-92600.json
- JSON Data
- https://api.osv.dev/v1/vulns/AZL-92600
- Upstream
- Published
- 2026-07-19T12:16:50Z
- Modified
- 2026-08-28T17:47:39Z
- Summary
- CVE-2026-53393 affecting package kernel for versions less than 6.6.145.2-1
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
nfsd: reset write verifier on deferred writeback errors
nfsd_vfs_write() and nfsd_commit() both call filemap_check_wb_err() to detect deferred writeback errors, but neither rotates the server's write verifier (nn->writeverf) when this check fails. Every other durable-storage-failure path in these functions calls commit_reset_write_verifier() before returning an error.
The missing rotation means clients holding UNSTABLE write data under the current verifier will COMMIT, receive the unchanged verifier back, and conclude their data is durable — silently dropping data that failed writeback. This violates the UNSTABLE+COMMIT durability contract (RFC 1813 §3.3.7, RFC 8881 §18.32).
Add commit_reset_write_verifier() calls at both filemap_check_wb_err() error sites, matching the pattern used by adjacent error paths in the same functions. The helper already filters -EAGAIN and -ESTALE internally, so the calls are unconditionally safe.
- References