From a85eba51f619d3e8c813a12871172f23689b28d6 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Thu, 29 Aug 2019 09:04:08 +0930 Subject: [PATCH] Tidy check_uvalue I don't see a need to calculate "ptr = start + uvalue" then compare "ptr" with "start" and "end". Given "start <= end" on entry, the "uvalue" comparison with "max_uvalue" ought to be sufficient to ensure "start + uvalue" is bounded by "start" and "end" regardless of the size of pointers and the unsigned dwarf_vma integer type. * dwarf.c (check_uvalue): Remove unnecessary pointer checks. --- binutils/ChangeLog | 4 ++++ binutils/dwarf.c | 9 +-------- 2 files changed, 5 insertions(+), 8 deletions(-) diff --git a/binutils/ChangeLog b/binutils/ChangeLog index 1148e9d990..98e660d167 100644 --- a/binutils/ChangeLog +++ b/binutils/ChangeLog @@ -1,3 +1,7 @@ +2019-08-29 Alan Modra + + * dwarf.c (check_uvalue): Remove unnecessary pointer checks. + 2019-08-28 Niklas Gürtler PR 24942 diff --git a/binutils/dwarf.c b/binutils/dwarf.c index 19ae1edca7..df924e4050 100644 --- a/binutils/dwarf.c +++ b/binutils/dwarf.c @@ -1848,16 +1848,9 @@ check_uvalue (const unsigned char * start, { dwarf_vma max_uvalue = end - start; - /* FIXME: Testing "(start + uvalue) < start" miscompiles with gcc 4.8.3 - running on an x86_64 host in 32-bit mode. So we pre-compute the value - here. */ - const unsigned char * ptr = start + uvalue; - /* See PR 17512: file: 008-103549-0.001:0.1. and PR 24829 for examples of where these tests are triggered. */ - if (uvalue > max_uvalue - || ptr > end - || ptr < start) + if (uvalue > max_uvalue) { warn (_("Corrupt attribute block length: %lx\n"), (long) uvalue); uvalue = max_uvalue; -- 2.34.1