diff --git a/Kconfig b/Kconfig
index 5a82c95..c8b86cd 100644
--- a/Kconfig
+++ b/Kconfig
@@ -267,6 +267,16 @@ config FIT_SIGNATURE
 	  format support in this case, enable it using
 	  CONFIG_IMAGE_FORMAT_LEGACY.
 
+config FIT_SIGNATURE_MAX_SIZE
+	hex "Max size of signed FIT structures"
+	depends on FIT_SIGNATURE
+	default 0x10000000
+	help
+	  This option sets a max size in bytes for verified FIT uImages.
+	  A sane value of 256MB protects corrupted DTB structures from overlapping
+	  device memory. Assure this size does not extend past expected storage
+	  space.
+
 config FIT_VERBOSE
 	bool "Show verbose messages when FIT images fail"
 	help
diff --git a/common/image-sig.c b/common/image-sig.c
index f65d883..8d2fd10 100644
--- a/common/image-sig.c
+++ b/common/image-sig.c
@@ -156,6 +156,11 @@ static int fit_image_setup_verify(struct image_sign_info *info,
 {
 	char *algo_name;
 
+	if (fdt_totalsize(fit) > CONFIG_FIT_SIGNATURE_MAX_SIZE) {
+		*err_msgp = "Total size too large";
+		return 1;
+	}
+
 	if (fit_image_hash_get_algo(fit, noffset, &algo_name)) {
 		*err_msgp = "Can't get hash algo property";
 		return -1;
diff --git a/test/py/tests/test_vboot.py b/test/py/tests/test_vboot.py
index ee939f2..3d25ec3 100644
--- a/test/py/tests/test_vboot.py
+++ b/test/py/tests/test_vboot.py
@@ -26,6 +26,7 @@ Tests run with both SHA1 and SHA256 hashing.
 
 import pytest
 import sys
+import struct
 import u_boot_utils as util
 
 @pytest.mark.boardspec('sandbox')
@@ -105,6 +106,26 @@ def test_vboot(u_boot_console):
         util.run_and_log(cons, [mkimage, '-F', '-k', tmpdir, '-K', dtb,
                                 '-r', fit])
 
+    def replace_fit_totalsize(size):
+        """Replace FIT header's totalsize with something greater.
+
+        The totalsize must be less than or equal to FIT_SIGNATURE_MAX_SIZE.
+        If the size is greater, the signature verification should return false.
+
+        Args:
+            size: The new totalsize of the header
+
+        Returns:
+            prev_size: The previous totalsize read from the header
+        """
+        total_size = 0
+        with open(fit, 'r+b') as handle:
+            handle.seek(4)
+            total_size = handle.read(4)
+            handle.seek(4)
+            handle.write(struct.pack(">I", size))
+        return struct.unpack(">I", total_size)[0]
+
     def test_with_algo(sha_algo):
         """Test verified boot with the given hash algorithm.
 
@@ -146,6 +167,18 @@ def test_vboot(u_boot_console):
         util.run_and_log(cons, [fit_check_sign, '-f', fit, '-k', tmpdir,
                                 '-k', dtb])
 
+        # Replace header bytes
+        bcfg = u_boot_console.config.buildconfig
+        max_size = int(bcfg.get('config_fit_signature_max_size', 0x10000000), 0)
+        existing_size = replace_fit_totalsize(max_size + 1)
+        run_bootm(sha_algo, 'Signed config with bad hash', 'Bad Data Hash', False)
+        cons.log.action('%s: Check overflowed FIT header totalsize' % sha_algo)
+
+        # Replace with existing header bytes
+        replace_fit_totalsize(existing_size)
+        run_bootm(sha_algo, 'signed config', 'dev+', True)
+        cons.log.action('%s: Check default FIT header totalsize' % sha_algo)
+
         # Increment the first byte of the signature, which should cause failure
         sig = util.run_and_log(cons, 'fdtget -t bx %s %s value' %
                                (fit, sig_node))
diff --git a/tools/Makefile b/tools/Makefile
index 5dd33ed..0c3341e 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -133,6 +133,7 @@ ifdef CONFIG_FIT_SIGNATURE
 # This affects include/image.h, but including the board config file
 # is tricky, so manually define this options here.
 HOST_EXTRACFLAGS	+= -DCONFIG_FIT_SIGNATURE
+HOST_EXTRACFLAGS	+= -DCONFIG_FIT_SIGNATURE_MAX_SIZE=$(CONFIG_FIT_SIGNATURE_MAX_SIZE)
 endif
 
 ifdef CONFIG_SYS_U_BOOT_OFFS