fdtgrep: Improve error handling with invalid device tree

This tool requires that the aliases node be the first node in the tree. But when it is not, it does not handle things gracefully. In fact it crashes. Fix this, and add a more helpful error message. Signed-off-by: Simon Glass <sjg@chromium.org> Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>

fdtgrep: Improve error handling with invalid device tree
This tool requires that the aliases node be the first node in the tree. But when it is not, it does not handle things gracefully. In fact it crashes. Fix this, and add a more helpful error message. Signed-off-by: Simon Glass <sjg@chromium.org> Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Simon Glass
1 parent ab761ce9f9
Showing 1 changed file with 10 additions and 4 deletions Side-by-side Diff
tools/fdtgrep.c
@@ -660,6 +660,8 @@
 		if (!ret)
 			count++;
 	}
+	if (ret && ret != -FDT_ERR_NOTFOUND)
+		return ret;
  
 	/* Find all the aliases and add those regions back in */
 	if (disp->add_aliases && count < max_regions) {
@@ -667,7 +669,11 @@
  
 		new_count = fdt_add_alias_regions(fdt, region, count,
 						  max_regions, &state);
-		if (new_count <= max_regions) {
+		if (new_count == -FDT_ERR_NOTFOUND) {
+			/* No alias node found */
+		} else if (new_count < 0) {
+			return new_count;
+		} else if (new_count <= max_regions) {
 			/*
 			* The alias regions will now be at the end of the list.
 			* Sort the regions by offset to get things into the
@@ -679,9 +685,6 @@
 		}
 	}
  
-	if (ret != -FDT_ERR_NOTFOUND)
-		return ret;
-
 	return count;
 }
  
@@ -807,6 +810,9 @@
 				disp->flags);
 		if (count < 0) {
 			report_error("fdt_find_regions", count);
+			if (count == -FDT_ERR_BADLAYOUT)
+				fprintf(stderr,
+					"/aliases node must come before all other nodes\n");
 			return -1;
 		}
 		if (count <= max_regions)
...	...	@@ -660,6 +660,8 @@
660	660	if (!ret)
661	661	count++;
662	662	}
	663	+ if (ret && ret != -FDT_ERR_NOTFOUND)
	664	+ return ret;
663	665
664	666	/* Find all the aliases and add those regions back in */
665	667	if (disp->add_aliases && count < max_regions) {
...	...	@@ -667,7 +669,11 @@
667	669
668	670	new_count = fdt_add_alias_regions(fdt, region, count,
669	671	max_regions, &state);
670		- if (new_count <= max_regions) {
	672	+ if (new_count == -FDT_ERR_NOTFOUND) {
	673	+ /* No alias node found */
	674	+ } else if (new_count < 0) {
	675	+ return new_count;
	676	+ } else if (new_count <= max_regions) {
671	677	/*
672	678	* The alias regions will now be at the end of the list.
673	679	* Sort the regions by offset to get things into the
...	...	@@ -679,9 +685,6 @@
679	685	}
680	686	}
681	687
682		- if (ret != -FDT_ERR_NOTFOUND)
683		- return ret;
684		-
685	688	return count;
686	689	}
687	690
...	...	@@ -807,6 +810,9 @@
807	810	disp->flags);
808	811	if (count < 0) {
809	812	report_error("fdt_find_regions", count);
	813	+ if (count == -FDT_ERR_BADLAYOUT)
	814	+ fprintf(stderr,
	815	+ "/aliases node must come before all other nodes\n");
810	816	return -1;
811	817	}
812	818	if (count <= max_regions)