From 9ab330dc7af2af28dac54b6198a7ec309087b819 Mon Sep 17 00:00:00 2001
From: Catalin Patulea <catalinp@google.com>
Date: Wed, 18 Aug 2021 07:13:45 -0700
Subject: [PATCH] 'Map' symbols: add pgoff to disambiguate multiple mappings on
 same object.

PiperOrigin-RevId: 391520785
Change-Id: Icb05e60f778acfb9fe6f519911ce54bec65fc4ff
---
 sandboxed_api/sandbox2/unwind/unwind.cc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/sandboxed_api/sandbox2/unwind/unwind.cc b/sandboxed_api/sandbox2/unwind/unwind.cc
index 0a12d2b..940e1fa 100644
--- a/sandboxed_api/sandbox2/unwind/unwind.cc
+++ b/sandboxed_api/sandbox2/unwind/unwind.cc
@@ -100,7 +100,11 @@ absl::StatusOr<std::map<uint64_t, std::string>> LoadSymbolsMap(pid_t pid) {
     // The maps entries are ordered and thus sorted with increasing adresses.
     // This means if there is a symbol @ entry.end, it will be overwritten in
     // the next iteration.
-    addr_to_symbol[entry.start] = absl::StrCat("map:", entry.path);
+    std::string map = absl::StrCat("map:", entry.path);
+    if (entry.pgoff) {
+      absl::StrAppend(&map, "+0x%x", entry.pgoff);
+    }
+    addr_to_symbol[entry.start] = map;
     addr_to_symbol[entry.end] = "";
 
     absl::StatusOr<ElfFile> elf =