[PATCH 1/1] nvme-tcp: fence TCP socket on transport error

[Chris Leech <cleech@redhat.com>]

Ensure that no further socket reads occur after a receive processing
error, either from io_work being re-scheduled or nvme_tcp_poll.

Failing to do so can result in unrecognised PDU payloads or TCP stream
garbage being processed as a C2H data PDU, and potentially start copying
the payload to an invalid destination after looking up a request using a
bogus command id.

Signed-off-by: Chris Leech <cleech@redhat.com>
---
 drivers/nvme/host/tcp.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 42c0598c31f2..49e8eb576527 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -888,6 +888,13 @@ static int nvme_tcp_recv_skb(read_descriptor_t *desc, struct sk_buff *skb,
 	size_t consumed = len;
 	int result;
 
+	if (!queue->rd_enabled) {
+		/* io_work or polling happening after receive error
+		 * waiting on error recovery
+		 */
+		return -EFAULT;
+	}
+
 	while (len) {
 		switch (nvme_tcp_recv_state(queue)) {
 		case NVME_TCP_RECV_PDU:
-- 
2.39.2