Add check in DwarfReader to avoid exception being caught

- In init, don't bother looking for a special note section
  if the note section size isn't greater than 12 bytes

Change-Id: I57d2d7b0229996edcb1b4149c391e91b0472beea
Reviewed-on: https://git.eclipse.org/r/25822
Tested-by: Hudson CI
Reviewed-by: Marc-Andre Laperle <marc-andre.laperle@ericsson.com>
Reviewed-by: Jeff Johnston <jjohnstn@redhat.com>
Tested-by: Jeff Johnston <jjohnstn@redhat.com>

1 files changed, 38 insertions, 36 deletions

diff --git a/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/utils/debug/dwarf/DwarfReader.java b/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/utils/debug/dwarf/DwarfReader.java
index c52462e62b9..7780ba02100 100644
--- a/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/utils/debug/dwarf/DwarfReader.java
+++ b/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/utils/debug/dwarf/DwarfReader.java
@@ -98,45 +98,47 @@ public class DwarfReader extends Dwarf implements ISymbolReader, ICompileOptions
 		for (Section section : sections) {
 			if (section.sh_type == Elf.Section.SHT_NOTE) {
 				ByteBuffer data = section.mapSectionData();
-				try {
-					// Read .note section, looking to see if it is named "GNU" and is of GNU_BUILD_ID type
-					@SuppressWarnings("unused")
-					int name_sz = read_4_bytes(data);
-					int data_sz = read_4_bytes(data);
-					int note_type = read_4_bytes(data);
+				if (data.remaining() > 12) {
+					try {
+						// Read .note section, looking to see if it is named "GNU" and is of GNU_BUILD_ID type
+						@SuppressWarnings("unused")
+						int name_sz = read_4_bytes(data);
+						int data_sz = read_4_bytes(data);
+						int note_type = read_4_bytes(data);
 
-					String noteName = readString(data);
-					String buildId = null;
-					if (noteName.equals("GNU") && note_type == Elf.Section.NT_GNU_BUILD_ID) { //$NON-NLS-1$
-						// We have the special GNU build-id note section.  Skip over the name to
-						// a 4-byte boundary.
-						byte[] byteArray = new byte[data_sz];
-						while ((data.position() & 0x3) != 0)
-							data.get();
-						int i = 0;
-						// Read in the hex bytes from the note section's data.
-						while (data.hasRemaining() && data_sz-- > 0) {
-							byteArray[i++] = data.get();
-						}
-						// The build-id location is taken by converting the binary bytes to hex string.
-						// The first byte is used as a directory specifier (e.g. 51/a4578fe2).
-						String bName = DatatypeConverter.printHexBinary(byteArray).toLowerCase();
-						buildId = bName.substring(0, 2) + "/" + bName.substring(2) + ".debug"; //$NON-NLS-1$ //$NON-NLS-2$
-						// The build-id file should be in the special directory /usr/lib/debug/.build-id
-						IPath buildIdPath = new Path("/usr/lib/debug/.build-id").append(buildId); //$NON-NLS-1$
-						File buildIdFile = buildIdPath.toFile();
-						if (buildIdFile.exists()) {
-							// if the debug file exists from above, open it and get the section info from it
-							Elf debugInfo = new Elf(buildIdFile.getCanonicalPath());
-							sections = debugInfo.getSections();
-							have_build_id = true;
-							debugInfoPath = new Path(buildIdFile.getCanonicalPath()).removeLastSegments(1);
-							break;
+						String noteName = readString(data);
+						String buildId = null;
+						if (noteName.equals("GNU") && note_type == Elf.Section.NT_GNU_BUILD_ID) { //$NON-NLS-1$
+							// We have the special GNU build-id note section.  Skip over the name to
+							// a 4-byte boundary.
+							byte[] byteArray = new byte[data_sz];
+							while ((data.position() & 0x3) != 0)
+								data.get();
+							int i = 0;
+							// Read in the hex bytes from the note section's data.
+							while (data.hasRemaining() && data_sz-- > 0) {
+								byteArray[i++] = data.get();
+							}
+							// The build-id location is taken by converting the binary bytes to hex string.
+							// The first byte is used as a directory specifier (e.g. 51/a4578fe2).
+							String bName = DatatypeConverter.printHexBinary(byteArray).toLowerCase();
+							buildId = bName.substring(0, 2) + "/" + bName.substring(2) + ".debug"; //$NON-NLS-1$ //$NON-NLS-2$
+							// The build-id file should be in the special directory /usr/lib/debug/.build-id
+							IPath buildIdPath = new Path("/usr/lib/debug/.build-id").append(buildId); //$NON-NLS-1$
+							File buildIdFile = buildIdPath.toFile();
+							if (buildIdFile.exists()) {
+								// if the debug file exists from above, open it and get the section info from it
+								Elf debugInfo = new Elf(buildIdFile.getCanonicalPath());
+								sections = debugInfo.getSections();
+								have_build_id = true;
+								debugInfoPath = new Path(buildIdFile.getCanonicalPath()).removeLastSegments(1);
+								break;
+							}
 						}
+					} catch (Exception e) {
+						e.printStackTrace();
+						CCorePlugin.log(e);
 					}
-				} catch (Exception e) {
-					e.printStackTrace();
-					CCorePlugin.log(e);
 				}
 			}
 		}