remoteproc: look for truncated firmware images
Make sure firmware isn't truncated before accessing its data.
Reported-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 080c056..f2354ce 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -191,6 +191,7 @@
* 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 @@
* 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 @@
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 @@
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_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 @@
* 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 @@
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 @@
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 @@
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 @@
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;