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Commit 9bc91231 authored by Ohad Ben-Cohen's avatar Ohad Ben-Cohen
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remoteproc: look for truncated firmware images 



Make sure firmware isn't truncated before accessing its data.

Reported-by: default avatarStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: default avatarOhad Ben-Cohen <ohad@wizery.com>
parent 63d667bf

drivers/remoteproc/remoteproc_core.c

+30 −5
Original line number Diff line number Diff line
@@ -191,6 +191,7 @@ static void *rproc_da_to_va(struct rproc *rproc, u64 da, int len) 
 * rproc_load_segments() - load firmware segments to memory

 * @rproc: remote processor which will be booted using these fw segments

 * @elf_data: the content of the ELF firmware image

 * @len: firmware size (in bytes)

 *

 * This function loads the firmware segments to memory, where the remote

 * processor expects them.
@@ -211,7 +212,8 @@ static void *rproc_da_to_va(struct rproc *rproc, u64 da, int len) 
 * directly allocate memory for every segment/resource. This is not yet

 * supported, though.

 */

static int rproc_load_segments(struct rproc *rproc, const u8 *elf_data)

static int

rproc_load_segments(struct rproc *rproc, const u8 *elf_data, size_t len)

{

	struct device *dev = rproc->dev;

	struct elf32_hdr *ehdr;
@@ -226,6 +228,7 @@ static int rproc_load_segments(struct rproc *rproc, const u8 *elf_data) 
		u32 da = phdr->p_paddr;

		u32 memsz = phdr->p_memsz;

		u32 filesz = phdr->p_filesz;

		u32 offset = phdr->p_offset;

		void *ptr;



		if (phdr->p_type != PT_LOAD)
@@ -241,6 +244,13 @@ static int rproc_load_segments(struct rproc *rproc, const u8 *elf_data) 
			break;

		}



		if (offset + filesz > len) {

			dev_err(dev, "truncated fw: need 0x%x avail 0x%x\n",

					offset + filesz, len);

			ret = -EINVAL;

			break;

		}



		/* grab the kernel address for this device address */

		ptr = rproc_da_to_va(rproc, da, memsz);

		if (!ptr) {
@@ -712,6 +722,7 @@ rproc_handle_virtio_rsc(struct rproc *rproc, struct fw_resource *rsc, int len) 
 * rproc_handle_resources() - find and handle the resource table

 * @rproc: the rproc handle

 * @elf_data: the content of the ELF firmware image

 * @len: firmware size (in bytes)

 * @handler: function that should be used to handle the resource table

 *

 * This function finds the resource table inside the remote processor's
@@ -725,7 +736,7 @@ rproc_handle_virtio_rsc(struct rproc *rproc, struct fw_resource *rsc, int len) 
 * processors that don't need a resource table.

 */

static int rproc_handle_resources(struct rproc *rproc, const u8 *elf_data,

					rproc_handle_resources_t handler)

				size_t len, rproc_handle_resources_t handler)



{

	struct elf32_hdr *ehdr;
@@ -743,6 +754,13 @@ static int rproc_handle_resources(struct rproc *rproc, const u8 *elf_data, 
			struct fw_resource *table = (struct fw_resource *)

						(elf_data + shdr->sh_offset);



			if (shdr->sh_offset + shdr->sh_size > len) {

				dev_err(rproc->dev,

					"truncated fw: need 0x%x avail 0x%x\n",

					shdr->sh_offset + shdr->sh_size, len);

				ret = -EINVAL;

			}



			ret = handler(rproc, table, shdr->sh_size);



			break;
@@ -833,6 +851,11 @@ static int rproc_fw_sanity_check(struct rproc *rproc, const struct firmware *fw) 


	ehdr = (struct elf32_hdr *)fw->data;



	if (fw->size < ehdr->e_shoff + sizeof(struct elf32_shdr)) {

		dev_err(dev, "Image is too small\n");

		return -EINVAL;

	}



	if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {

		dev_err(dev, "Image is corrupted (bad magic)\n");

		return -EINVAL;
@@ -887,14 +910,15 @@ static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw) 
	rproc->bootaddr = ehdr->e_entry;



	/* handle fw resources which are required to boot rproc */

	ret = rproc_handle_resources(rproc, fw->data, rproc_handle_boot_rsc);

	ret = rproc_handle_resources(rproc, fw->data, fw->size,

						rproc_handle_boot_rsc);

	if (ret) {

		dev_err(dev, "Failed to process resources: %d\n", ret);

		goto clean_up;

	}



	/* load the ELF segments to memory */

	ret = rproc_load_segments(rproc, fw->data);

	ret = rproc_load_segments(rproc, fw->data, fw->size);

	if (ret) {

		dev_err(dev, "Failed to load program segments: %d\n", ret);

		goto clean_up;
@@ -937,7 +961,8 @@ static void rproc_fw_config_virtio(const struct firmware *fw, void *context) 
		goto out;



	/* does the fw supports any virtio devices ? */

	ret = rproc_handle_resources(rproc, fw->data, rproc_handle_virtio_rsc);

	ret = rproc_handle_resources(rproc, fw->data, fw->size,

						rproc_handle_virtio_rsc);

	if (ret) {

		dev_info(dev, "No fw virtio device was found\n");

		goto out;