NFS: Fix a race when updating an existing write

Summary

In the Linux kernel, the following vulnerability has been resolved: NFS: Fix a race when updating an existing write After nfs_lock_and_join_requests() tests for whether the request is still attached to the mapping, nothing prevents a call to nfs_inode_remove_request() from succeeding until we actually lock the page group. The reason is that whoever called nfs_inode_remove_request() doesn't necessarily have a lock on the page group head. So in order to avoid races, let's take the page group lock earlier in nfs_lock_and_join_requests(), and hold it across the removal of the request in nfs_inode_remove_request().

Timeline

1. Sep 5, 2025, 5:21 PM UTCCVE published
2. Jun 10, 2026, 8:42 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Oct 15, 2026, 1:08 AM UTCRecord last updated

Affected versions

• Linux Linux

  From bd37d6fce184836bd5e7cd90ce40116a4fadaf2a · fixed in 0ff42a32784e0f2cb46a46da8e9f473538c13e1b; From bd37d6fce184836bd5e7cd90ce40116a4fadaf2a · fixed in f230d40147cc37eb3aef4d50e2e2c06ea73d9a77; From bd37d6fce184836bd5e7cd90ce40116a4fadaf2a · fixed in c32e3c71aaa1c1ba05da88605e2ddd493c58794f; From bd37d6fce184836bd5e7cd90ce40116a4fadaf2a · fixed in 181feb41f0b268e6288bf9a7b984624d7fe2031d; From bd37d6fce184836bd5e7cd90ce40116a4fadaf2a · fixed in 92278ae36935a54e65fef9f8ea8efe7e80481ace; From bd37d6fce184836bd5e7cd90ce40116a4fadaf2a · fixed in 202a3432d21ac060629a760fff3b0a39859da3ea; From bd37d6fce184836bd5e7cd90ce40116a4fadaf2a · fixed in 76d2e3890fb169168c73f2e4f8375c7cc24a765e

• Linux Linux

  4.14

• KernelLinux

  From 4.14.0 · fixed in 5.10.242; From 5.11.0 · fixed in 5.15.191; From 5.16.0 · fixed in 6.1.150; From 6.2.0 · fixed in 6.6.104; From 6.7.0 · fixed in 6.12.44; From 6.13.0 · fixed in 6.16.4

References 7