From afd438d363dfb36601536ab13893e1758c1e0969 Mon Sep 17 00:00:00 2001
From: Andrew Gaul <andrew@gaul.org>
Date: Wed, 24 Jul 2019 15:22:14 -0700
Subject: [PATCH] Access FdEntity metadata while holding fdent_lock

Create copies to avoid thread races.  Found via ThreadSanitizer.
Follows on to ecf13a8cb9d08406af454f318b8a2b1eb7f37995.
---
 src/fdcache.cpp | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/fdcache.cpp b/src/fdcache.cpp
index 834dcb2..a2d72e6 100644
--- a/src/fdcache.cpp
+++ b/src/fdcache.cpp
@@ -1479,7 +1479,15 @@ int FdEntity::RowFlush(const char* tpath, bool force_sync)
 {
   int result = 0;
 
-  S3FS_PRN_INFO3("[tpath=%s][path=%s][fd=%d]", SAFESTRPTR(tpath), path.c_str(), fd);
+  std::string tmppath;
+  headers_t tmporgmeta;
+  {
+    AutoLock auto_lock(&fdent_lock);
+    tmppath = path;
+    tmporgmeta = orgmeta;
+  }
+
+  S3FS_PRN_INFO3("[tpath=%s][path=%s][fd=%d]", SAFESTRPTR(tpath), tmppath.c_str(), fd);
 
   if(-1 == fd){
     return -EBADF;
@@ -1554,10 +1562,10 @@ int FdEntity::RowFlush(const char* tpath, bool force_sync)
     }
 
     if(pagelist.Size() >= S3fsCurl::GetMultipartSize() && !nomultipart){
-      result = S3fsCurl::ParallelMultipartUploadRequest(tpath ? tpath : path.c_str(), orgmeta, fd);
+      result = S3fsCurl::ParallelMultipartUploadRequest(tpath ? tpath : tmppath.c_str(), tmporgmeta, fd);
     }else{
       S3fsCurl s3fscurl(true);
-      result = s3fscurl.PutRequest(tpath ? tpath : path.c_str(), orgmeta, fd);
+      result = s3fscurl.PutRequest(tpath ? tpath : tmppath.c_str(), tmporgmeta, fd);
     }
 
     // seek to head of file.