CVE-2026-46135
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk28th percentile - higher than 28% of all known CVEs
Summary
A race condition was found in the Linux kernel's NVMe/TCP driver (nvmet-tcp) between ICReq handling and queue teardown. Lack of synchronization allows overwriting the queue state, leading to a double kref_put and potential memory corruption.
Risk Assessment
The organization risks system crashes or undefined kernel behavior if an NVMe/TCP host sends an ICReq and immediately closes the connection. This can disrupt NVMe-oF storage services.
Recommendation
Apply the kernel security patch that serializes queue state transitions with state_lock immediately. Update to a kernel version containing the fix commit.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: fix race between ICReq handling and queue teardown nvmet_tcp_handle_icreq() updates queue->state after sending an Initialization Connection Response (ICResp), but it does so without serializing against target-side queue teardown. If an NVMe/TCP host sends an Initialization Connection Request (ICReq) and immediately closes the connection, target-side teardown may start in softirq context before io_work drains the already buffered ICReq. In that case, nvmet_tcp_schedule_release_queue() sets queue->state to NVMET_TCP_Q_DISCONNECTING and drops the queue reference under state_lock. If io_work later processes that ICReq, nvmet_tcp_handle_icreq() can still overwrite the state back to NVMET_TCP_Q_LIVE. That defeats the DISCONNECTING-state guard in nvmet_tcp_schedule_release_queue() and allows a later socket state change to re-enter teardown and issue a second kref_put() on an already released queue. The ICResp send failure path has the same problem. If teardown has already moved the queue to DISCONNECTING, a send error can still overwrite the state with NVMET_TCP_Q_FAILED, again reopening the window for a second teardown path to drop the queue reference. Fix this by serializing both post-send state transitions with state_lock and bailing out if teardown has already started. Use -ESHUTDOWN as an internal sentinel for that bail-out path rather than propagating it as a transport error like -ECONNRESET. Keep nvmet_tcp_socket_error() setting rcv_state to NVMET_TCP_RECV_ERR before honoring that sentinel so receive-side parsing stays quiesced until the existing release path completes.

