Commit 0cacbc89 authored by Daniel Stenberg's avatar Daniel Stenberg
Browse files

always allocates at least 64 bytes for real, and damages them before free

parent 6753c3c7

lib/memdebug.c

+30 −8
Original line number Original line Diff line number Diff line
@@ -47,6 +47,11 @@ 




/* DONT include memdebug.h here! */

/* DONT include memdebug.h here! */





struct memdebug {

  int size;

  char mem[1];

};



/*

/*

 * Note that these debug functions are very simple and they are meant to

 * Note that these debug functions are very simple and they are meant to

 * remain so. For advanced analysis, record a log file and write perl scripts

 * remain so. For advanced analysis, record a log file and write perl scripts
@@ -67,15 +72,21 @@ void curl_memdebug(const char *logname) 
}

}









void *curl_domalloc(size_t size, int line, const char *source)

void *curl_domalloc(size_t wantedsize, int line, const char *source)

{

{

  void *mem=(malloc)(size);

  void *mem;

  size_t size;



  /* alloc at least 64 bytes */

  size = wantedsize>64?wantedsize:64;



  mem=(malloc)(size);

  if(mem)

  if(mem)

    /* fill memory with junk */

    /* fill memory with junk */

    memset(mem, 0xA5, size);

    memset(mem, 0xA5, size);

  if(logfile)

  if(logfile && source)

    fprintf(logfile, "MEM %s:%d malloc(%d) = %p\n",

    fprintf(logfile, "MEM %s:%d malloc(%d) = %p\n",

            source, line, size, mem);

            source, line, wantedsize, mem);

  return mem;

  return mem;

}

}
@@ -90,20 +101,28 @@ char *curl_dostrdup(const char *str, int line, const char *source) 
    exit(2);

    exit(2);

  }

  }





  mem=(strdup)(str);

  len=strlen(str)+1;

  len=strlen(str)+1;



  mem=curl_domalloc(len, 0, NULL); /* NULL prevents logging */

  memcpy(mem, str, len);



  if(logfile)

  if(logfile)

    fprintf(logfile, "MEM %s:%d strdup(%p) (%d) = %p\n",

    fprintf(logfile, "MEM %s:%d strdup(%p) (%d) = %p\n",

            source, line, str, len, mem);

            source, line, str, len, mem);

  return mem;

  return mem;

}

}





void *curl_dorealloc(void *ptr, size_t size, int line, const char *source)

void *curl_dorealloc(void *ptr, size_t wantedsize,

                     int line, const char *source)

{

{

  void *mem=(realloc)(ptr, size);

  void *mem;



  size_t size = wantedsize>64?wantedsize:64;



  mem=(realloc)(ptr, size);

  if(logfile)

  if(logfile)

    fprintf(logfile, "MEM %s:%d realloc(%p, %d) = %p\n",

    fprintf(logfile, "MEM %s:%d realloc(%p, %d) = %p\n",

            source, line, ptr, size, mem);

            source, line, ptr, wantedsize, mem);

  return mem;

  return mem;

}

}
@@ -114,7 +133,10 @@ void curl_dofree(void *ptr, int line, const char *source) 
            source, line);

            source, line);

    exit(2);

    exit(2);

  }

  }

  /* we know this is least 64 bytes, destroy this much */

  memset(ptr, 0x13, 64);





  /* free for real */

  (free)(ptr);

  (free)(ptr);





  if(logfile)

  if(logfile)