commit 7f1eec317db79627b473c5b149a22a1b20d1f68f Author: Mark Wielaard Date: Wed Apr 9 11:33:23 2014 +0200 CVE-2014-0172 Check for overflow before calling malloc to uncompress data. https://bugzilla.redhat.com/show_bug.cgi?id=1085663 Reported-by: Florian Weimer Signed-off-by: Mark Wielaard 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;