Merge tag 'devicetree-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull DeviceTree updates from Rob Herring:

 - new tool 'dtx_diff' to diff DT files

 - sync kernel's dtc/libfdt to current dtc repo master

 - fix for reserved memory regions located in highmem

 - document standard unit suffixes for DT properties

 - various DT binding doc updates

* tag 'devicetree-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  of: Add vendor prefix for eGalax_eMPIA Technology Inc
  Input: ads7846: Add description how to use internal reference (ADS7846)
  ARM: realview: add EB syscon variants to bindings
  devicetree: bindings: ARM: Use "uV" for micro-volt
  serial: fsl-imx-uart: Fix typo in fsl,dte-mode description
  of: add 'const' for of_property_*_string*() parameter '*np'
  of/unittest: fix infinite loop in of_unittest_destroy_tracked_overlays()
  of: alloc anywhere from memblock if range not specified
  kbuild: Allow using host dtc instead of kernel's copy
  of: resolver: Add missing of_node_get and of_node_put
  of: Add United Radiant Technology Corporation vendor prefix
  dt/bindings: add documentation on standard property unit suffixes
  scripts/dtc: Update to upstream commit b06e55c88b9b
  ARM: boot: Add an implementation of strnlen for libfdt
  scripts/dtc: dtx_diff - add info to error message
  dtc: create tool to diff device trees

1 files changed, 7 insertions, 6 deletions

diff --git a/scripts/dtc/libfdt/fdt.c b/scripts/dtc/libfdt/fdt.c
index 2ce6a44179de..22286a1aaeaf 100644
--- a/scripts/dtc/libfdt/fdt.c
+++ b/scripts/dtc/libfdt/fdt.c
@@ -76,18 +76,19 @@ int fdt_check_header(const void *fdt)
 
 const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
 {
-	const char *p;
+	unsigned absoffset = offset + fdt_off_dt_struct(fdt);
+
+	if ((absoffset < offset)
+	    || ((absoffset + len) < absoffset)
+	    || (absoffset + len) > fdt_totalsize(fdt))
+		return NULL;
 
 	if (fdt_version(fdt) >= 0x11)
 		if (((offset + len) < offset)
 		    || ((offset + len) > fdt_size_dt_struct(fdt)))
 			return NULL;
 
-	p = _fdt_offset_ptr(fdt, offset);
-
-	if (p + len < p)
-		return NULL;
-	return p;
+	return _fdt_offset_ptr(fdt, offset);
 }
 
 uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)