https://bugzilla.redhat.com/show_bug.cgi?id=1085663

Reported-by: Florian Weimer <fweimer at redhat.com>
Signed-off-by: Mark Wielaard <mjw at redhat.com>
---
 libdw/dwarf_begin_elf.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/libdw/dwarf_begin_elf.c b/libdw/dwarf_begin_elf.c
index 79daeac..34ea373 100644
--- a/libdw/dwarf_begin_elf.c
+++ b/libdw/dwarf_begin_elf.c
@@ -282,6 +282,12 @@ check_section (Dwarf *result, GElf_Ehdr *ehdr, Elf_Scn *scn, bool inscngrp)
 	    memcpy (&size, data->d_buf + 4, sizeof size);
 	    size = be64toh (size);
 
+	    /* Check for unsigned overflow so malloc always allocated
+	       enough memory for both the Elf_Data header and the
+	       uncompressed section data.  */
+	    if (unlikely (sizeof (Elf_Data) + size < size))
+	      break;
+
 	    Elf_Data *zdata = malloc (sizeof (Elf_Data) + size);
 	    if (unlikely (zdata == NULL))
 	      break;
-- 
1.7.1