SUNRPC: wait for in-flight client TLS handshake callback

Summary

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: wait for in-flight client TLS handshake callback xs_tls_handshake_sync() gives xs_tls_handshake_done() a reference to the lower transport before submitting the handshake request. On timeout or signal, the synchronous waiter drops that reference after calling tls_handshake_cancel(). handshake_req_cancel() returns false when handshake_complete() has already marked the request complete. In that case the completion callback can still be running, so dropping the callback-owned reference in the waiter can free the lower transport before xs_tls_handshake_done() stores xprt_err or drops its own reference. If cancellation loses to completion, wait until xs_tls_handshake_done() signals handshake_done and let the callback release its reference. This mirrors the server-side handshake lifetime handling and keeps the timeout or signal return value unchanged.

Timeline

1. Sep 11, 2026, 7:44 PM UTCCVE published
2. Oct 19, 2026, 8:48 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 75eb6af7acdf566c68d61e98e67ee2f235201c02 · fixed in fb43997407bc17ee39bac81ab708101312e255f5; From 75eb6af7acdf566c68d61e98e67ee2f235201c02 · fixed in 15431820f448e09f8029b670d5c82aa5917d4625; From 75eb6af7acdf566c68d61e98e67ee2f235201c02 · fixed in 1de391e8b94e31b45c19c16dbf315e294810c7de; From 75eb6af7acdf566c68d61e98e67ee2f235201c02 · fixed in 7fbb6d2ab0391eb8d1f1a68e6bc263ef02cea61b; From 75eb6af7acdf566c68d61e98e67ee2f235201c02 · fixed in a89dd597458848b463d284b15e42a8078beeb046

• Linux Linux

  6.5

• KernelLinux

  From 6.5.0 · fixed in 6.6.157; From 6.7.0 · fixed in 6.12.109; From 6.13.0 · fixed in 6.18.50; From 6.19.0 · fixed in 7.2.4

References 5