From 69a583281f21ee439943807c8c7bf07efee97cfb Mon Sep 17 00:00:00 2001
From: John Reiser <jreiser@BitWagon.com>
Date: Sun, 16 Dec 2018 16:00:15 -0800
Subject: [PATCH] MemBuffer::subref() for 64-bit offsets; better diagnosis for
 bad .e_shoff

https://github.com/upx/upx/issues/235 (POC14)
	modified:   mem.cpp
	modified:   mem.h
	modified:   p_lx_elf.cpp
---
 src/p_lx_elf.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/p_lx_elf.cpp b/src/p_lx_elf.cpp
index 2f84062f..e81e5c0b 100644
--- a/src/p_lx_elf.cpp
+++ b/src/p_lx_elf.cpp
@@ -4248,6 +4248,7 @@ void PackLinuxElf64::unpack(OutputFile *fo)
         overlay_offset -= sizeof(linfo);
         xct_off = overlay_offset;
         e_shoff = get_te64(&ehdri.e_shoff);
+        ibuf.subref("bad .e_shoff %#lx for %#lx", e_shoff, sizeof(Elf64_Shdr) * e_shnum);
         if (e_shoff && e_shnum) { // --android-shlib
             shdri = (Elf64_Shdr /*const*/ *)ibuf.subref(
                 "bad Shdr table", e_shoff, sizeof(Elf64_Shdr)*e_shnum);
@@ -5125,6 +5126,7 @@ void PackLinuxElf32::unpack(OutputFile *fo)
         overlay_offset -= sizeof(linfo);
         xct_off = overlay_offset;
         e_shoff = get_te32(&ehdri.e_shoff);
+        ibuf.subref("bad .e_shoff %#x for %#x", e_shoff, sizeof(Elf32_Shdr) * e_shnum);
         if (e_shoff && e_shnum) { // --android-shlib
             shdri = (Elf32_Shdr /*const*/ *)ibuf.subref(
                 "bad Shdr table", e_shoff, sizeof(Elf32_Shdr)*e_shnum);