remoteproc: make sure we're parsing a 32bit firmware

Make sure we're parsing a 32bit image, since we only support
the ELF32 binary format at this point.

This should prevent unexpected behavior with non 32bit binaries.
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Grosen <mgrosen@ti.com>
Cc: Suman Anna <s-anna@ti.com>
Cc: Fernando Guzman Lugo <fernando.lugo@ti.com>
Cc: Rob Clark <rob@ti.com>
Cc: Ludovic BARRE <ludovic.barre@stericsson.com>
Cc: Loic PALLARDY <loic.pallardy@stericsson.com>
Cc: Omar Ramirez Luna <omar.luna@linaro.org>

drivers/remoteproc/remoteproc_core.c

@@ -840,6 +840,7 @@ static int rproc_fw_sanity_check(struct rproc *rproc, const struct firmware *fw)
 	const char *name = rproc->firmware;
 	struct device *dev = rproc->dev;
 	struct elf32_hdr *ehdr;
+	char class;
 
 	if (!fw) {
 		dev_err(dev, "failed to load %s\n", name);
@@ -853,6 +854,13 @@ static int rproc_fw_sanity_check(struct rproc *rproc, const struct firmware *fw)
 
 	ehdr = (struct elf32_hdr *)fw->data;
 
+	/* We only support ELF32 at this point */
+	class = ehdr->e_ident[EI_CLASS];
+	if (class != ELFCLASS32) {
+		dev_err(dev, "Unsupported class: %d\n", class);
+		return -EINVAL;
+	}
+
 	/* We assume the firmware has the same endianess as the host */
 # ifdef __LITTLE_ENDIAN
 	if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB) {