IT

Tracker / CVE-2026-53393

CVE-2026-53393

Medium 5.5

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.

Affected products and versions

linux linux_kernel · 5.10.124 → 5.10.261
linux linux_kernel · 5.15.49 → 5.15.212
linux linux_kernel · 5.17 → 6.1.178
linux linux_kernel · 6.13 → 6.18.38
linux linux_kernel · 6.19 → 7.1.3
linux linux_kernel · 6.2 → 6.6.145
linux linux_kernel · 6.7 → 6.12.95

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References