Linux Kernel CVE-2026-53063

The Linux kernel's device mapper (dm) cache target provides a block-level caching layer and supports several operational modes including passthrough, write-through, and write-back. In passthrough mode, writes bypass the cache and go directly to the origin device. The vulnerable function invalidate_remove() handles write hit bios - block I/O requests that arrive during cache invalidation sequences. It correctly constructs a remapped overwrite_bio pointing to the origin device, but due to incomplete control flow, it drops the bio immediately without submitting it via dm_io() or equivalent, causing the bio to never complete and the issuing process to hang. The fix introduces a new invalidate_committed() continuation that submits the remapped write after metadata commit, and repairs invalidate_complete() to preserve the original error status rather than unconditionally calling bio_io_error(). The affected CPE is cpe:2.3:a:linux:linux:*:*:*:*:*:*:*:* across multiple stable branches introduced at commit b29d4986d0da1a27cd35917cdb433672f5c95d7f. No CWE is assigned; the root cause class maps most closely to CWE-670 (Always-Incorrect Control Flow Implementation).