dmtcp: fix buffer overflow due to too long ld-linux.so path

fixes #29565

pkgs/os-specific/linux/dmtcp/default.nix

@@ -13,15 +13,14 @@ stdenv.mkDerivation rec {
 
   dontDisableStatic = true;
 
+  patches = [ ./ld-linux-so-buffer-size.patch ];
+
   postPatch = ''
     patchShebangs .
 
     substituteInPlace configure \
       --replace '#define ELF_INTERPRETER "$interp"' \
                 "#define ELF_INTERPRETER \"$(cat $NIX_CC/nix-support/dynamic-linker)\""
-  '';
-
-  preConfigure = ''
     substituteInPlace src/dmtcp_coordinator.cpp \
       --replace /bin/bash ${stdenv.shell}
     substituteInPlace util/gdb-add-symbol-file \

pkgs/os-specific/linux/dmtcp/ld-linux-so-buffer-size.patch

@@ -0,0 +1,11 @@
+--- dmtcp-2.5.1-src/src/util_exec.cpp	2017-09-19 13:36:22.947587034 +0200
++++ dmtcp-2.5.1-src/src/util_exec.cpp	2017-09-19 13:36:32.221313460 +0200
+@@ -178,7 +178,7 @@
+ 
+ static string ld_linux_so_path(int version, bool is32bitElf = false)
+ {
+-  char buf[80];
++  char buf[128];
+ #if (defined(__x86_64__) || defined(__aarch64__)) && !defined(CONFIG_M32)
+   if (is32bitElf) {
+     sprintf(buf, "/lib/ld-linux.so.%d", version);