summary refs log tree commit diff
diff options
context:
space:
mode:
-rw-r--r--drivers/soc/qcom/mdt_loader.c88
-rw-r--r--include/linux/soc/qcom/mdt_loader.h2
2 files changed, 87 insertions, 3 deletions
diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c
index 1c488024c698..1c970d6dd532 100644
--- a/drivers/soc/qcom/mdt_loader.c
+++ b/drivers/soc/qcom/mdt_loader.c
@@ -74,6 +74,66 @@ ssize_t qcom_mdt_get_size(const struct firmware *fw)
 }
 EXPORT_SYMBOL_GPL(qcom_mdt_get_size);
 
+/**
+ * qcom_mdt_read_metadata() - read header and metadata from mdt or mbn
+ * @fw:		firmware of mdt header or mbn
+ * @data_len:	length of the read metadata blob
+ *
+ * The mechanism that performs the authentication of the loading firmware
+ * expects an ELF header directly followed by the segment of hashes, with no
+ * padding inbetween. This function allocates a chunk of memory for this pair
+ * and copy the two pieces into the buffer.
+ *
+ * In the case of split firmware the hash is found directly following the ELF
+ * header, rather than at p_offset described by the second program header.
+ *
+ * The caller is responsible to free (kfree()) the returned pointer.
+ *
+ * Return: pointer to data, or ERR_PTR()
+ */
+void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len)
+{
+	const struct elf32_phdr *phdrs;
+	const struct elf32_hdr *ehdr;
+	size_t hash_offset;
+	size_t hash_size;
+	size_t ehdr_size;
+	void *data;
+
+	ehdr = (struct elf32_hdr *)fw->data;
+	phdrs = (struct elf32_phdr *)(ehdr + 1);
+
+	if (ehdr->e_phnum < 2)
+		return ERR_PTR(-EINVAL);
+
+	if (phdrs[0].p_type == PT_LOAD || phdrs[1].p_type == PT_LOAD)
+		return ERR_PTR(-EINVAL);
+
+	if ((phdrs[1].p_flags & QCOM_MDT_TYPE_MASK) != QCOM_MDT_TYPE_HASH)
+		return ERR_PTR(-EINVAL);
+
+	ehdr_size = phdrs[0].p_filesz;
+	hash_size = phdrs[1].p_filesz;
+
+	data = kmalloc(ehdr_size + hash_size, GFP_KERNEL);
+	if (!data)
+		return ERR_PTR(-ENOMEM);
+
+	/* Is the header and hash already packed */
+	if (ehdr_size + hash_size == fw->size)
+		hash_offset = phdrs[0].p_filesz;
+	else
+		hash_offset = phdrs[1].p_offset;
+
+	memcpy(data, fw->data, ehdr_size);
+	memcpy(data + ehdr_size, fw->data + hash_offset, hash_size);
+
+	*data_len = ehdr_size + hash_size;
+
+	return data;
+}
+EXPORT_SYMBOL_GPL(qcom_mdt_read_metadata);
+
 static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
 			   const char *firmware, int pas_id, void *mem_region,
 			   phys_addr_t mem_phys, size_t mem_size,
@@ -86,12 +146,14 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
 	phys_addr_t mem_reloc;
 	phys_addr_t min_addr = PHYS_ADDR_MAX;
 	phys_addr_t max_addr = 0;
+	size_t metadata_len;
 	size_t fw_name_len;
 	ssize_t offset;
+	void *metadata;
 	char *fw_name;
 	bool relocate = false;
 	void *ptr;
-	int ret;
+	int ret = 0;
 	int i;
 
 	if (!fw || !mem_region || !mem_phys || !mem_size)
@@ -109,7 +171,15 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
 		return -ENOMEM;
 
 	if (pas_init) {
-		ret = qcom_scm_pas_init_image(pas_id, fw->data, fw->size);
+		metadata = qcom_mdt_read_metadata(fw, &metadata_len);
+		if (IS_ERR(metadata)) {
+			ret = PTR_ERR(metadata);
+			goto out;
+		}
+
+		ret = qcom_scm_pas_init_image(pas_id, metadata, metadata_len);
+
+		kfree(metadata);
 		if (ret) {
 			dev_err(dev, "invalid firmware metadata\n");
 			goto out;
@@ -170,7 +240,19 @@ static int __qcom_mdt_load(struct device *dev, const struct firmware *fw,
 
 		ptr = mem_region + offset;
 
-		if (phdr->p_filesz) {
+		if (phdr->p_filesz && phdr->p_offset < fw->size) {
+			/* Firmware is large enough to be non-split */
+			if (phdr->p_offset + phdr->p_filesz > fw->size) {
+				dev_err(dev,
+					"failed to load segment %d from truncated file %s\n",
+					i, firmware);
+				ret = -EINVAL;
+				break;
+			}
+
+			memcpy(ptr, fw->data + phdr->p_offset, phdr->p_filesz);
+		} else if (phdr->p_filesz) {
+			/* Firmware not large enough, load split-out segments */
 			sprintf(fw_name + fw_name_len - 3, "b%02d", i);
 			ret = request_firmware_into_buf(&seg_fw, fw_name, dev,
 							ptr, phdr->p_filesz);
diff --git a/include/linux/soc/qcom/mdt_loader.h b/include/linux/soc/qcom/mdt_loader.h
index 944b06aefb0f..e600baec6825 100644
--- a/include/linux/soc/qcom/mdt_loader.h
+++ b/include/linux/soc/qcom/mdt_loader.h
@@ -21,4 +21,6 @@ int qcom_mdt_load_no_init(struct device *dev, const struct firmware *fw,
 			  const char *fw_name, int pas_id, void *mem_region,
 			  phys_addr_t mem_phys, size_t mem_size,
 			  phys_addr_t *reloc_base);
+void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len);
+
 #endif