From: Sagi Grimberg sagi@grimberg.me
commit 25e1f67eda4a19c91dc05c84d6d413c53efb447b upstream.
We should not access request members after the last send, even to determine if indeed it was the last data payload send. The reason is that a completion could have arrived and trigger a new execution of the request which overridden these members. This was fixed by commit 825619b09ad3 ("nvme-tcp: fix possible use-after-completion").
Commit e371af033c56 broke that assumption again to address cases where multiple r2t pdus are sent per request. To fix it, we need to record the request data_sent and data_len and after the payload network send we reference these counters to determine weather we should advance the request iterator.
Fixes: e371af033c56 ("nvme-tcp: fix incorrect h2cdata pdu offset accounting") Reported-by: Keith Busch kbusch@kernel.org Cc: stable@vger.kernel.org # 5.10+ 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: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/nvme/host/tcp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -910,12 +910,14 @@ static void nvme_tcp_fail_request(struct static int nvme_tcp_try_send_data(struct nvme_tcp_request *req) { struct nvme_tcp_queue *queue = req->queue; + int req_data_len = req->data_len;
while (true) { struct page *page = nvme_tcp_req_cur_page(req); size_t offset = nvme_tcp_req_cur_offset(req); size_t len = nvme_tcp_req_cur_length(req); bool last = nvme_tcp_pdu_last_send(req, len); + int req_data_sent = req->data_sent; int ret, flags = MSG_DONTWAIT;
if (last && !queue->data_digest && !nvme_tcp_queue_more(queue)) @@ -942,7 +944,7 @@ static int nvme_tcp_try_send_data(struct * 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) + if (req_data_sent + ret < req_data_len) nvme_tcp_advance_req(req, ret);
/* fully successful last send in current PDU */