Patch "nvmet-tcp: move send/recv error handling in the send/recv methods instead of call-sites" has been added to the 5.4-stable tree

[<gregkh@xxxxxxxxxxxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    nvmet-tcp: move send/recv error handling in the send/recv methods instead of call-sites

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nvmet-tcp-move-send-recv-error-handling-in-the-send-recv-methods-instead-of-call-sites.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From 0236d3437909ff888e5c79228e2d5a851651c4c6 Mon Sep 17 00:00:00 2001
From: Sagi Grimberg <sagi@xxxxxxxxxxx>
Date: Mon, 18 May 2020 10:47:48 -0700
Subject: nvmet-tcp: move send/recv error handling in the send/recv methods instead of call-sites

From: Sagi Grimberg <sagi@xxxxxxxxxxx>

commit 0236d3437909ff888e5c79228e2d5a851651c4c6 upstream.

Have routines handle errors and just bail out of the poll loop.
This simplifies the code and will help as we may enhance the poll
loop logic and these are somewhat in the way.

Signed-off-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Dragos-Marian Panait <dragos.panait@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/nvme/target/tcp.c |   43 ++++++++++++++++++++++++-------------------
 1 file changed, 24 insertions(+), 19 deletions(-)

--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -321,6 +321,14 @@ static void nvmet_tcp_fatal_error(struct
 		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
 }
 
+static void nvmet_tcp_socket_error(struct nvmet_tcp_queue *queue, int status)
+{
+	if (status == -EPIPE || status == -ECONNRESET)
+		kernel_sock_shutdown(queue->sock, SHUT_RDWR);
+	else
+		nvmet_tcp_fatal_error(queue);
+}
+
 static int nvmet_tcp_map_data(struct nvmet_tcp_cmd *cmd)
 {
 	struct nvme_sgl_desc *sgl = &cmd->req.cmd->common.dptr.sgl;
@@ -714,11 +722,15 @@ static int nvmet_tcp_try_send(struct nvm
 
 	for (i = 0; i < budget; i++) {
 		ret = nvmet_tcp_try_send_one(queue, i == budget - 1);
-		if (ret <= 0)
+		if (unlikely(ret < 0)) {
+			nvmet_tcp_socket_error(queue, ret);
+			goto done;
+		} else if (ret == 0) {
 			break;
+		}
 		(*sends)++;
 	}
-
+done:
 	return ret;
 }
 
@@ -1167,11 +1179,15 @@ static int nvmet_tcp_try_recv(struct nvm
 
 	for (i = 0; i < budget; i++) {
 		ret = nvmet_tcp_try_recv_one(queue);
-		if (ret <= 0)
+		if (unlikely(ret < 0)) {
+			nvmet_tcp_socket_error(queue, ret);
+			goto done;
+		} else if (ret == 0) {
 			break;
+		}
 		(*recvs)++;
 	}
-
+done:
 	return ret;
 }
 
@@ -1196,27 +1212,16 @@ static void nvmet_tcp_io_work(struct wor
 		pending = false;
 
 		ret = nvmet_tcp_try_recv(queue, NVMET_TCP_RECV_BUDGET, &ops);
-		if (ret > 0) {
+		if (ret > 0)
 			pending = true;
-		} else if (ret < 0) {
-			if (ret == -EPIPE || ret == -ECONNRESET)
-				kernel_sock_shutdown(queue->sock, SHUT_RDWR);
-			else
-				nvmet_tcp_fatal_error(queue);
+		else if (ret < 0)
 			return;
-		}
 
 		ret = nvmet_tcp_try_send(queue, NVMET_TCP_SEND_BUDGET, &ops);
-		if (ret > 0) {
-			/* transmitted message/data */
+		if (ret > 0)
 			pending = true;
-		} else if (ret < 0) {
-			if (ret == -EPIPE || ret == -ECONNRESET)
-				kernel_sock_shutdown(queue->sock, SHUT_RDWR);
-			else
-				nvmet_tcp_fatal_error(queue);
+		else if (ret < 0)
 			return;
-		}
 
 	} while (pending && ops < NVMET_TCP_IO_WORK_BUDGET);
 


Patches currently in stable-queue which might be from sagi@xxxxxxxxxxx are

queue-5.4/nvmet-tcp-move-send-recv-error-handling-in-the-send-recv-methods-instead-of-call-sites.patch
queue-5.4/nvmet-tcp-fix-a-possible-uaf-in-queue-intialization-setup.patch