From e5ef2728bd44c528fe8800b0b0326ab69589229d Mon Sep 17 00:00:00 2001
From: Arjun Moudgil <arjunmoudgil@fb.com>
Date: Tue, 15 Sep 2020 20:46:35 -0400
Subject: [PATCH] Added check for if info.dli_sname is NULL

Check if info.dli_sname is NULL,
If the image containing addr is found, but no nearest symbol was found, the dli_sname and dli_saddr fields are set to NULL.
---
 src/symbolize.cc | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/symbolize.cc b/src/symbolize.cc
index 76a1b0f..7767c90 100644
--- a/src/symbolize.cc
+++ b/src/symbolize.cc
@@ -857,11 +857,13 @@ static ATTRIBUTE_NOINLINE bool SymbolizeAndDemangle(void *pc, char *out,
                                                     int out_size) {
   Dl_info info;
   if (dladdr(pc, &info)) {
-    if ((int)strlen(info.dli_sname) < out_size) {
-      strcpy(out, info.dli_sname);
-      // Symbolization succeeded.  Now we try to demangle the symbol.
-      DemangleInplace(out, out_size);
-      return true;
+    if (info.dli_sname) {
+      if ((int)strlen(info.dli_sname) < out_size) {
+        strcpy(out, info.dli_sname);
+        // Symbolization succeeded.  Now we try to demangle the symbol.
+        DemangleInplace(out, out_size);
+        return true;
+      }
     }
   }
   return false;