[PATCH] libdw: Don't leak arange if we cannot figure out which CU it belongs to.

[PATCH] libdw: Don't leak arange if we cannot figure out which CU it belongs to.

[Mark Wielaard]

In the unlikely case that __libdw_findcu fails to find the associated
CU we would leak one arange because it wasn't linked into the arangelist
list yet. Make sure to free it immediately.

Signed-off-by: Mark Wielaard <mark@klomp.org>
---
 libdw/ChangeLog          | 5 +++++
 libdw/dwarf_getaranges.c | 7 ++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/libdw/ChangeLog b/libdw/ChangeLog
index f0ce901..661fa9d 100644
--- a/libdw/ChangeLog
+++ b/libdw/ChangeLog
@@ -1,5 +1,10 @@
 2018-06-05  Mark Wielaard  <mark@klomp.org>
 
+	* dwarf_getaranges (dwarf_getaranges): Free new_arange if
+	__libdw_findcu fails.
+
+2018-06-05  Mark Wielaard  <mark@klomp.org>
+
 	* dwarf_getsrclines.c (read_srclines): Define dirarray early and
 	check whether or not it is equal to dirstack on exit/out before
 	cleanup.
diff --git a/libdw/dwarf_getaranges.c b/libdw/dwarf_getaranges.c
index 50a98cf..bff9c86 100644
--- a/libdw/dwarf_getaranges.c
+++ b/libdw/dwarf_getaranges.c
@@ -197,7 +197,12 @@ dwarf_getaranges (Dwarf *dbg, Dwarf_Aranges **aranges, size_t *naranges)
 	  /* We store the actual CU DIE offset, not the CU header offset.  */
 	  Dwarf_CU *cu = __libdw_findcu (dbg, offset, false);
 	  if (unlikely (cu == NULL))
-	    goto fail;
+	    {
+	      /* We haven't gotten a chance to link in the new_arange
+		 into the arangelist, don't leak it.  */
+	      free (new_arange);
+	      goto fail;
+	    }
 	  new_arange->arange.offset = __libdw_first_die_off_from_cu (cu);
 
 	  new_arange->next = arangelist;
-- 
1.8.3.1

Re: [PATCH] libdw: Don't leak arange if we cannot figure out which CU it belongs to.

[Mark Wielaard]

On Tue, 2018-06-05 at 22:44 +0200, Mark Wielaard wrote:
> In the unlikely case that __libdw_findcu fails to find the associated
> CU we would leak one arange because it wasn't linked into the arangelist
> list yet. Make sure to free it immediately.

Pushed to master.