MGM: geotree: Fix wrong memcpy invocation in FsId2NodeIdxMap

This structure allocates a char array [pStrLen + sizeof(tFastTreeIdx)] at size;
the first pStrLen * size is reserved for the buffer and the rest is storing the
indices
The memcpy invocation however copied sizeof(char*) * pStreLen * pSize previously
which would copy 8 times the intended size leading to hard to debug segfaults
whereas it should be only copying pSize * pStrLen

Fixes: EOS-6506
Signed-off-by: Abhishek Lekshmanan <abhishek.lekshmanan@cern.ch>

Author: theanalyst

mgm/geotree/SchedulingFastTree.hh

@@ -450,7 +450,7 @@ public:
     dest->pSize = pSize;
     // copy the data
     memcpy(dest->pNodeIdxs, pNodeIdxs, sizeof(tFastTreeIdx)*pSize);
-    memcpy(dest->pBuffer, pBuffer, sizeof(char*)*pSize * pStrLen);
+    memcpy(dest->pBuffer, pBuffer, sizeof(char) * pSize * pStrLen);
     return 0;
   }