{"cve":"CVE-2026-99111","nvd":{"published":"2026-10-28T11:17:30.520","modified":"2026-10-28T11:17:30.520","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix data corruption with concurrent writes and O_TRUNC\n\ncifs_do_truncate() flushes dirty pages with filemap_write_and_wait()\nand truncates the file on the server, but in the old code both\noperations ran without holding i_rwsem or invalidate_lock.  A\nconcurrent buffered write via netfs_perform_write() -- which only\nneeds i_rwsem shared -- could dirty new pages after the flush but\nbefore the local truncation, and those pages would be silently\ndiscarded by cifs_setsize() -> truncate_pagecache().\n\nFix by acquiring inode_lock (exclusive i_rwsem) and\nfilemap_invalidate_lock at the top of cifs_do_truncate(), so the\nentire flush-truncate-resize sequence is atomic with respect to:\n\n  - buffered writes (blocked by exclusive i_rwsem, since\n    netfs_start_io_write takes i_rwsem shared),\n  - read page faults (blocked by exclusive invalidate_lock, since\n    filemap_fault takes it shared),\n  - writeback collection (blocked by netfs_wb_begin/netfs_wb_end\n    around the server truncate and local resize, since\n    netfs_writepages also acquires the wb lock).","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/4d143608a0445443a85c9b29f4c9f8e63d5dbfc9","https://git.kernel.org/stable/c/a8603b52b39f520ea8a34def74c23fba87396d3e","https://git.kernel.org/stable/c/ffa66fdc7d35b890606767c4d2c7ac26b4d90a99"],"products":[],"source":"nvd","synced_at":"2026-10-28T11:37:51.394563875+00:00"},"epss":null,"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}