Module: rtems
Branch: master
Commit: 0d851d49c5299975168b3187d90530008c47d958
Changeset: http://git.rtems.org/rtems/commit/?id=0d851d49c5299975168b3187d90530008c47d958
Author: David Gibson <david at gibson.dropbear.id.au>
Date: Sun Mar 18 00:12:12 2018 +1100
libfdt: Add fdt_check_full() function
This new function implements a complete and thorough check of an fdt blob's
structure. Given a buffer containing an fdt, it should return 0 only if
the fdt within is structurally sound in all regards. It doesn't check
anything about the blob's contents (i.e. the actual values of the nodes and
properties), of course.
Signed-off-by: David Gibson <david at gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik at ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik at ozlabs.ru>
Reviewed-by: Simon Glass <sjg at chromium.org>
---
cpukit/dtc/libfdt/fdt_ro.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++
cpukit/include/libfdt.h | 2 ++
2 files changed, 65 insertions(+)
diff --git a/cpukit/dtc/libfdt/fdt_ro.c b/cpukit/dtc/libfdt/fdt_ro.c
index c74b962..4ba7c93 100644
--- a/cpukit/dtc/libfdt/fdt_ro.c
+++ b/cpukit/dtc/libfdt/fdt_ro.c
@@ -857,3 +857,66 @@ int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
return offset; /* error from fdt_next_node() */
}
+
+int fdt_check_full(const void *fdt, size_t bufsize)
+{
+ int err;
+ int num_memrsv;
+ int offset, nextoffset = 0;
+ uint32_t tag;
+ unsigned depth = 0;
+ const void *prop;
+ const char *propname;
+
+ if (bufsize < FDT_V1_SIZE)
+ return -FDT_ERR_TRUNCATED;
+ err = fdt_check_header(fdt);
+ if (err != 0)
+ return err;
+ if (bufsize < fdt_totalsize(fdt))
+ return -FDT_ERR_TRUNCATED;
+
+ num_memrsv = fdt_num_mem_rsv(fdt);
+ if (num_memrsv < 0)
+ return num_memrsv;
+
+ while (1) {
+ offset = nextoffset;
+ tag = fdt_next_tag(fdt, offset, &nextoffset);
+
+ if (nextoffset < 0)
+ return nextoffset;
+
+ switch (tag) {
+ case FDT_NOP:
+ break;
+
+ case FDT_END:
+ if (depth != 0)
+ return -FDT_ERR_BADSTRUCTURE;
+ return 0;
+
+ case FDT_BEGIN_NODE:
+ depth++;
+ if (depth > INT_MAX)
+ return -FDT_ERR_BADSTRUCTURE;
+ break;
+
+ case FDT_END_NODE:
+ if (depth == 0)
+ return -FDT_ERR_BADSTRUCTURE;
+ depth--;
+ break;
+
+ case FDT_PROP:
+ prop = fdt_getprop_by_offset(fdt, offset, &propname,
+ &err);
+ if (!prop)
+ return err;
+ break;
+
+ default:
+ return -FDT_ERR_INTERNAL;
+ }
+ }
+}
diff --git a/cpukit/include/libfdt.h b/cpukit/include/libfdt.h
index b81d046..79e4d82 100644
--- a/cpukit/include/libfdt.h
+++ b/cpukit/include/libfdt.h
@@ -298,6 +298,8 @@ int fdt_move(const void *fdt, void *buf, int bufsize);
/* Read-only functions */
/**********************************************************************/
+int fdt_check_full(const void *fdt, size_t bufsize);
+
/**
* fdt_get_string - retrieve a string from the strings block of a device tree
* @fdt: pointer to the device tree blob