From 34bf6df75d17625b0042df7e9e09b7cb1d88790d Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bart.vanassche@sandisk.com>
Date: Wed, 30 Nov 2016 21:12:01 -0800
Subject: [PATCH] iscsi-scst: Restore msg->msg_iov check

---
 iscsi-scst/kernel/nthread.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/iscsi-scst/kernel/nthread.c b/iscsi-scst/kernel/nthread.c
index ed041cc04..4c60d4b3c 100644
--- a/iscsi-scst/kernel/nthread.c
+++ b/iscsi-scst/kernel/nthread.c
@@ -697,6 +697,10 @@ static int do_recv(struct iscsi_conn *conn)
 	mm_segment_t oldfs;
 	struct msghdr *msg;
 	int read_size;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0)
+	struct iovec *first_iov;
+	int first_len;
+#endif
 
 	EXTRACHECKS_BUG_ON(conn->read_cmnd == NULL);
 
@@ -717,6 +721,8 @@ restart:
 	read_size = msg->msg_iter.count;
 #else
 	read_size = conn->read_size;
+	first_iov = msg->msg_iov;
+	first_len = first_iov->iov_len;
 #endif
 
 	oldfs = get_fs();
@@ -746,7 +752,7 @@ restart:
 		sBUG_ON(msg->msg_iter.count + res != read_size);
 		res = msg->msg_iter.count;
 #else
-		/* To do: restore msg->msg_iov check. */
+		sBUG_ON((res >= first_len) && (first_iov->iov_len != 0));
 		conn->read_size -= res;
 		res = conn->read_size;
 #endif