CVE-2026-23240

In the Linux kernel, the following vulnerability has been resolved:

tls: Fix race condition in tls_sw_cancel_work_tx()

This issue was discovered during a code audit.

After cancel_delayed_work_sync() is called from tls_sk_proto_close(),

tx_work_handler() can still be scheduled from paths such as the

Delayed ACK handler or ksoftirqd.

As a result, the tx_work_handler() worker may dereference a freed

TLS object.

The following is a simple race scenario:

cpu0 cpu1

tls_sk_proto_close()

tls_sw_cancel_work_tx()

tls_write_space()

tls_sw_write_space()

if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))

set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);

cancel_delayed_work_sync(&ctx->tx_work.work);

schedule_delayed_work(&tx_ctx->tx_work.work, 0);

To prevent this race condition, cancel_delayed_work_sync() is

replaced with disable_delayed_work_sync().