[binutils-gdb] Fix memory leak in python.c:do_start_initialization

[Andreas Arnez <arnez at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=3f2a3564b1c3872e4a380f2484d40ce2495a4835

commit 3f2a3564b1c3872e4a380f2484d40ce2495a4835
Author: Philipp Rudo <prudo@linux.vnet.ibm.com>
Date:   Thu Mar 23 12:22:11 2017 +0100

    Fix memory leak in python.c:do_start_initialization
    
    When intializing Python the path to the python binary is build the
    following way
    
    progname = concat (ldirname (python_libdir), SLASH_STRING, "bin",
    		   SLASH_STRING, "python", (char *) NULL);
    
    This is problematic as both concat and ldirname allocate memory for the
    string they return.  Thus the memory allocated by ldirname cannot be
    accessed afterwards causing a memory leak.  Fix it by temporarily storing
    libdir in a variable and xfree it after concat.
    
    gdb/ChangeLog:
    	python/python.c (do_start_initialization): Fix memory leak.

Diff:
---
 gdb/ChangeLog       | 4 ++++
 gdb/python/python.c | 4 +++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 8bb9e21..f69a27e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2017-03-23  Philipp Rudo  <prudo@linux.vnet.ibm.com>
+
+	python/python.c (do_start_initialization): Fix memory leak.
+
 2017-03-22  Simon Marchi  <simon.marchi@polymtl.ca>
 
 	* inf-ptrace.c (inf_ptrace_xfer_partial): Get pid from ptid
diff --git a/gdb/python/python.c b/gdb/python/python.c
index 73fb3d0..d814252 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -1550,8 +1550,10 @@ do_start_initialization ()
      /foo/bin/python
      /foo/lib/pythonX.Y/...
      This must be done before calling Py_Initialize.  */
-  progname = concat (ldirname (python_libdir), SLASH_STRING, "bin",
+  const char *libdir = ldirname (python_libdir);
+  progname = concat (libdir, SLASH_STRING, "bin",
 		     SLASH_STRING, "python", (char *) NULL);
+  xfree (libdir);
 #ifdef IS_PY3K
   oldloc = xstrdup (setlocale (LC_ALL, NULL));
   setlocale (LC_ALL, "");