Linux kernel (net/tls): The async crypto callback signalled completion before scheduling the transmit work, so the

Impact

The async crypto callback signalled completion before scheduling the transmit work, so the submitting thread could exit and free the socket context while the callback was still queueing work against it - a use-after-free on the kTLS transmit path.

Who can reach it

Remote peers drive the record flow; the race closes on a socket close or syscall return, which an attacker can encourage by resetting connections against a kTLS sender. Any kTLS TX socket on the node, no privilege or device node needed. Requires an async-capable AEAD driver.

What to do

Boot a kernel carrying the linked stable commits, along with the rest of the tls async series. Interim: disable async crypto offload for kTLS.

References