diff --git a/include/iscsi-private.h b/include/iscsi-private.h
index fd4c5b7e..4842fce3 100644
--- a/include/iscsi-private.h
+++ b/include/iscsi-private.h
@@ -107,8 +107,8 @@ struct iscsi_context {
 	uint32_t target_max_recv_data_segment_length;
 	enum iscsi_initial_r2t want_initial_r2t;
 	enum iscsi_initial_r2t use_initial_r2t;
-	enum iscsi_initial_r2t want_immediate_data;
-	enum iscsi_initial_r2t use_immediate_data;
+	enum iscsi_immediate_data want_immediate_data;
+	enum iscsi_immediate_data use_immediate_data;
 };
 
 #define ISCSI_PDU_IMMEDIATE		       0x40
diff --git a/include/iscsi.h b/include/iscsi.h
index 4582ffd6..6064f8c9 100644
--- a/include/iscsi.h
+++ b/include/iscsi.h
@@ -195,7 +195,8 @@ enum iscsi_header_digest {
 	ISCSI_HEADER_DIGEST_NONE        = 0,
 	ISCSI_HEADER_DIGEST_NONE_CRC32C = 1,
 	ISCSI_HEADER_DIGEST_CRC32C_NONE = 2,
-	ISCSI_HEADER_DIGEST_CRC32C      = 3
+	ISCSI_HEADER_DIGEST_CRC32C      = 3,
+	ISCSI_HEADER_DIGEST_LAST        = ISCSI_HEADER_DIGEST_CRC32C
 };
 
 /*
diff --git a/lib/init.c b/lib/init.c
index 826e04f8..705e4c5a 100644
--- a/lib/init.c
+++ b/lib/init.c
@@ -282,6 +282,10 @@ iscsi_set_header_digest(struct iscsi_context *iscsi,
 				"logged in");
 		return -1;
 	}
+	if ((unsigned)header_digest > ISCSI_HEADER_DIGEST_LAST) {
+		iscsi_set_error(iscsi, "invalid header digest value");
+		return -1;
+	}
 
 	iscsi->want_header_digest = header_digest;
 
diff --git a/lib/login.c b/lib/login.c
index 0d4d7e9b..24348e82 100644
--- a/lib/login.c
+++ b/lib/login.c
@@ -188,6 +188,9 @@ iscsi_login_add_headerdigest(struct iscsi_context *iscsi, struct iscsi_pdu *pdu)
 	case ISCSI_HEADER_DIGEST_CRC32C:
 		str = (char *)"HeaderDigest=CRC32C";
 		break;
+	default:
+		iscsi_set_error(iscsi, "invalid header digest value");
+		return -1;
 	}
 
 	if (iscsi_pdu_add_data(iscsi, pdu, (unsigned char *)str, strlen(str)+1)
diff --git a/lib/scsi-lowlevel.c b/lib/scsi-lowlevel.c
index 0aff97ab..eb45d880 100644
--- a/lib/scsi-lowlevel.c
+++ b/lib/scsi-lowlevel.c
@@ -805,6 +805,10 @@ scsi_modesense_datain_unmarshall(struct scsi_task *task)
 		case SCSI_MODESENSE_PAGECODE_INFORMATIONAL_EXCEPTIONS_CONTROL:
 			scsi_parse_mode_informational_exceptions_control(task, pos, mp);
 			break;
+		default:
+			/* TODO: process other pages, or add raw data to struct
+			 * scsi_mode_page.  */
+			break;
 		}
 
 		mp->next  = ms->pages;
@@ -1082,7 +1086,7 @@ scsi_get_task_private_ptr(struct scsi_task *task)
 
 struct scsi_data_buffer {
        struct scsi_data_buffer *next;
-       int len;
+       uint32_t len;
        unsigned char *data;
 };
 
@@ -1091,6 +1095,9 @@ scsi_task_add_data_in_buffer(struct scsi_task *task, int len, unsigned char *buf
 {
 	struct scsi_data_buffer *data_buf;
 
+	if (len < 0) {
+		return -1;
+	}
 	data_buf = scsi_malloc(task, sizeof(struct scsi_data_buffer));
 	if (data_buf == NULL) {
 		return -1;