From: Sagi Grimberg sagi@grimberg.me
[ Upstream commit e371af033c560b9dd1e861f8f0b503142bf0a06c ]
When the controller sends us multiple r2t PDUs in a single request we need to account for it correctly as our send/recv context run concurrently (i.e. we get a new r2t with r2t_offset before we updated our iterator and req->data_sent marker). This can cause wrong offsets to be sent to the controller.
To fix that, we will first know that this may happen only in the send sequence of the last page, hence we will take the r2t_offset to the h2c PDU data_offset, and in nvme_tcp_try_send_data loop, we make sure to increment the request markers also when we completed a PDU but we are expecting more r2t PDUs as we still did not send the entire data of the request.
Fixes: 825619b09ad3 ("nvme-tcp: fix possible use-after-completion") Reported-by: Nowak, Lukasz Lukasz.Nowak@Dell.com Tested-by: Nowak, Lukasz Lukasz.Nowak@Dell.com Signed-off-by: Sagi Grimberg sagi@grimberg.me Reviewed-by: Keith Busch kbusch@kernel.org Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/tcp.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 19a711395cdc..fd28a23d45ed 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -614,7 +614,7 @@ static int nvme_tcp_setup_h2c_data_pdu(struct nvme_tcp_request *req, cpu_to_le32(data->hdr.hlen + hdgst + req->pdu_len + ddgst); data->ttag = pdu->ttag; data->command_id = nvme_cid(rq); - data->data_offset = cpu_to_le32(req->data_sent); + data->data_offset = pdu->r2t_offset; data->data_length = cpu_to_le32(req->pdu_len); return 0; } @@ -940,7 +940,15 @@ static int nvme_tcp_try_send_data(struct nvme_tcp_request *req) nvme_tcp_ddgst_update(queue->snd_hash, page, offset, ret);
- /* fully successful last write*/ + /* + * update the request iterator except for the last payload send + * in the request where we don't want to modify it as we may + * compete with the RX path completing the request. + */ + if (req->data_sent + ret < req->data_len) + nvme_tcp_advance_req(req, ret); + + /* fully successful last send in current PDU */ if (last && ret == len) { if (queue->data_digest) { nvme_tcp_ddgst_final(queue->snd_hash, @@ -952,7 +960,6 @@ static int nvme_tcp_try_send_data(struct nvme_tcp_request *req) } return 1; } - nvme_tcp_advance_req(req, ret); } return -EAGAIN; }