libdw: Fix memory corruption in libdw_find_split_unit.

Found by valgrind when trying to match a split unit from a .dwo file
that doesn't contain the split unit (as first) match. We would close
the split Dwarf too early, before we had inspected all units in it.

Add a testcase that simulates this. Which failed (at least under valgrind
as run by make distcheck) before the fix.

Signed-off-by: Mark Wielaard <[email protected]>

3 files changed, 40 insertions, 2 deletions

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 7ac6bd3c..4d69515b 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,9 @@
+2018-05-28  Mark Wielaard  <[email protected]>
+
+	* run-readelf-info-plus.sh: New test.
+	* Makefile.am (TESTS): Add run-readelf-info-plus.sh.
+	(EXTRA_DIST): Likewise.
+
 2018-04-29  Mark Wielaard  <[email protected]>
 
 	* run-readelf-addr.sh: New test.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 4cd06656..e935410a 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -93,7 +93,7 @@ TESTS = run-arextract.sh run-arsymtest.sh run-ar.sh newfile test-nlist \
 	run-ranlib-test2.sh run-ranlib-test3.sh run-ranlib-test4.sh \
 	run-addrscopes.sh run-strings-test.sh run-funcscopes.sh \
 	run-find-prologues.sh run-allregs.sh run-addrcfi.sh \
-	run-nm-self.sh run-readelf-self.sh \
+	run-nm-self.sh run-readelf-self.sh run-readelf-info-plus.sh \
 	run-varlocs-self.sh run-exprlocs-self.sh \
 	run-readelf-test1.sh run-readelf-test2.sh run-readelf-test3.sh \
 	run-readelf-test4.sh run-readelf-twofiles.sh \
@@ -197,7 +197,8 @@ EXTRA_DIST = run-arextract.sh run-arsymtest.sh run-ar.sh \
 	     run-elflint-self.sh run-ranlib-test.sh run-ranlib-test2.sh \
 	     run-ranlib-test3.sh run-ranlib-test4.sh \
 	     run-addrscopes.sh run-strings-test.sh run-funcscopes.sh \
-	     run-nm-self.sh run-readelf-self.sh run-addrcfi.sh \
+	     run-nm-self.sh run-readelf-self.sh run-readelf-info-plus.sh \
+	     run-addrcfi.sh \
 	     run-varlocs-self.sh run-exprlocs-self.sh \
 	     run-find-prologues.sh run-allregs.sh run-native-test.sh \
 	     run-addrname-test.sh run-dwfl-bug-offline-rel.sh \
diff --git a/tests/run-readelf-info-plus.sh b/tests/run-readelf-info-plus.sh
new file mode 100755
index 00000000..ee1db021
--- /dev/null
+++ b/tests/run-readelf-info-plus.sh
@@ -0,0 +1,31 @@
+#! /bin/sh
+# Test for --debug-dump=info+ and finding split unit (in wrong file).
+# Copyright (C) 2018 Red Hat, Inc.
+# This file is part of elfutils.
+#
+# This file is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# elfutils is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. $srcdir/test-subr.sh
+
+# see tests/testfile-dwarf-45.source
+testfiles testfile-splitdwarf-5
+testfiles testfile-world5.dwo
+
+# note, wrong file, renamed as if this contains the correct dwo...
+tempfiles testfile-hello5.dwo
+cp testfile-world5.dwo testfile-hello5.dwo
+
+testrun ${abs_top_builddir}/src/readelf --debug-dump=info+ testfile-splitdwarf-5
+
+exit 0