diff --git a/src/msgbuf.h b/src/msgbuf.h
index 38c7055..6f50b05 100644
--- a/src/msgbuf.h
+++ b/src/msgbuf.h
@@ -1056,12 +1056,12 @@
 		char: pldm_msgbuf_insert_array_char)(dst, count, src,          \
 						     src_count)
 
-LIBPLDM_CC_NONNULL
+LIBPLDM_CC_NONNULL_ARGS(1)
 LIBPLDM_CC_ALWAYS_INLINE int pldm_msgbuf_span_required(struct pldm_msgbuf *ctx,
 						       size_t required,
 						       void **cursor)
 {
-	if (!ctx->cursor || *cursor) {
+	if (!ctx->cursor || (cursor && *cursor)) {
 		return pldm_msgbuf_status(ctx, EINVAL);
 	}
 
@@ -1080,7 +1080,9 @@
 		return pldm_msgbuf_status(ctx, EOVERFLOW);
 	}
 
-	*cursor = ctx->cursor;
+	if (cursor) {
+		*cursor = ctx->cursor;
+	}
 	ctx->cursor += required;
 
 	return 0;
diff --git a/tests/msgbuf.cpp b/tests/msgbuf.cpp
index 111200a..7ddd2fb 100644
--- a/tests/msgbuf.cpp
+++ b/tests/msgbuf.cpp
@@ -873,6 +873,7 @@
     struct pldm_msgbuf* ctx = &_ctx;
     uint8_t src[6] = {0x11, 0x22, 0x44, 0x55, 0x66, 0x77};
     uint8_t buf[6] = {0};
+    const size_t required = 4;
     uint16_t testVal;
     [[maybe_unused]] uint8_t* retBuff = NULL;
 
@@ -887,6 +888,8 @@
     ASSERT_EQ(pldm_msgbuf_init_cc(ctxExtract, 0, buf, sizeof(buf)),
               PLDM_SUCCESS);
     EXPECT_EQ(pldm_msgbuf_extract_uint16(ctxExtract, &testVal), PLDM_SUCCESS);
+    EXPECT_EQ(pldm_msgbuf_span_required(ctxExtract, required, NULL),
+              PLDM_SUCCESS);
 
     EXPECT_EQ(pldm_msgbuf_destroy(ctxExtract), PLDM_SUCCESS);
     EXPECT_EQ(pldm_msgbuf_destroy(ctx), PLDM_SUCCESS);