From: Mark Wielaard To: elfutils-devel at sourceware dot org Cc: Mark Wielaard Subject: [PATCH] readelf: Fix off by one sanity check in handle_gnu_hash. Date: Fri, 24 Mar 2017 12:15:02 +0100 Message-Id: <1490354102-21353-1-git-send-email-mark@klomp.org> X-Mailer: git-send-email 1.8.3.1 We sanity check to make sure we don't index outside the chain array by testing inner > max_nsyms. But inner is a zero-based index, while max_nsyms is the maximum number. Change the check to inner >= max_nsyms. https://sourceware.org/bugzilla/show_bug.cgi?id=21299 Signed-off-by: Mark Wielaard --- src/readelf.c | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/src/readelf.c b/src/readelf.c index 8d96ba3..490b6d5 100644 --- a/src/readelf.c +++ b/src/readelf.c @@ -3263,7 +3263,7 @@ handle_gnu_hash (Ebl *ebl, Elf_Scn *scn, GElf_Shdr *shdr, size_t shstrndx) ++nsyms; if (maxlength < ++lengths[cnt]) ++maxlength; - if (inner > max_nsyms) + if (inner >= max_nsyms) goto invalid_data; } while ((chain[inner++] & 1) == 0); -- 1.8.3.1