averello/linux-stable-mirror
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2026-09-22 09:34:56 +02:00
Code Issues Packages Projects Releases Wiki Activity

nvmet-tcp: fix race between ICReq handling and queue teardown

Browse Source 
commit 5293a8882c upstream.

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.

Fixes: c46a6465bac2 ("nvmet-tcp: add NVMe over TCP target driver")
Cc: stable@vger.kernel.org
Reported-by: Shivam Kumar <skumar47@syr.edu>
Tested-by: Shivam Kumar <kumar.shivam43666@gmail.com>
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
[ context diff adaptation: drop `queue->state = NVMET_TCP_Q_FAILED` since
 the enum introduced in 6.7, 675b453e02 ("nvmet-tcp: enable TLS handshake
 upcall" ]
Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Chaitanya Kulkarni
2026-07-04 13:42:25 +02:00
committed by Greg Kroah-Hartman
parent e8852ae298
commit 5f0b95ef68
1 changed files with 28 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files
drivers/nvme/target/tcp.c
+28 -1
View File
@@ -380,6 +380,19 @@ static int nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd)
static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue)
{
/*
* Keep rcv_state at RECV_ERR even for the internal -ESHUTDOWN path.
* nvmet_tcp_handle_icreq() can return -ESHUTDOWN after the ICReq has
* already been consumed and queue teardown has started.
*
* If nvmet_tcp_data_ready() or nvmet_tcp_write_space() queues
* nvmet_tcp_io_work() again before nvmet_tcp_release_queue_work()
* cancels it, the queue must not keep that old receive state.
* Otherwise the next nvmet_tcp_io_work() run can reach
* nvmet_tcp_done_recv_pdu() and try to handle the same ICReq again.
*
* That is why queue->rcv_state needs to be updated before we return.
*/
queue->rcv_state = NVMET_TCP_RECV_ERR;
if (queue->nvme_sq.ctrl)
nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl);
@@ -935,10 +948,24 @@ static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue)
iov.iov_base = icresp;
iov.iov_len = sizeof(*icresp);
ret = kernel_sendmsg(queue->sock, &msg, &iov, 1, iov.iov_len);
if (ret < 0)
if (ret < 0) {
spin_lock_bh(&queue->state_lock);
if (queue->state == NVMET_TCP_Q_DISCONNECTING) {
spin_unlock_bh(&queue->state_lock);
return -ESHUTDOWN;
}
spin_unlock_bh(&queue->state_lock);
return ret; /* queue removal will cleanup */
}
spin_lock_bh(&queue->state_lock);
if (queue->state == NVMET_TCP_Q_DISCONNECTING) {
spin_unlock_bh(&queue->state_lock);
/* Tell nvmet_tcp_socket_error() teardown is in progress. */
return -ESHUTDOWN;
}
queue->state = NVMET_TCP_Q_LIVE;
spin_unlock_bh(&queue->state_lock);
nvmet_prepare_receive_pdu(queue);
return 0;
}