shadow/lib/pwmem.c
Iker Pedrosa d594243fbb lib: check NULL before freeing passwd data
Add an additional NULL check condition in spw_free() and pw_free() to
avoid freeing an already empty pointer.

Signed-off-by: Iker Pedrosa <ipedrosa@redhat.com>
2021-11-19 12:09:59 +01:00

109 lines
3.2 KiB
C

/*
* Copyright (c) 1990 - 1994, Julianne Frances Haugh
* Copyright (c) 1996 - 2000, Marek Michałkiewicz
* Copyright (c) 2001 , Michał Moskal
* Copyright (c) 2003 - 2005, Tomasz Kłoczko
* Copyright (c) 2007 - 2013, Nicolas François
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the copyright holders or contributors may not be used to
* endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <config.h>
#ident "$Id$"
#include <stdio.h>
#include "defines.h"
#include "prototypes.h"
#include "pwio.h"
/*@null@*/ /*@only@*/struct passwd *__pw_dup (const struct passwd *pwent)
{
struct passwd *pw;
pw = (struct passwd *) malloc (sizeof *pw);
if (NULL == pw) {
return NULL;
}
/* The libc might define other fields. They won't be copied. */
memset (pw, 0, sizeof *pw);
pw->pw_uid = pwent->pw_uid;
pw->pw_gid = pwent->pw_gid;
/*@-mustfreeonly@*/
pw->pw_name = strdup (pwent->pw_name);
/*@=mustfreeonly@*/
if (NULL == pw->pw_name) {
pw_free(pw);
return NULL;
}
/*@-mustfreeonly@*/
pw->pw_passwd = strdup (pwent->pw_passwd);
/*@=mustfreeonly@*/
if (NULL == pw->pw_passwd) {
pw_free(pw);
return NULL;
}
/*@-mustfreeonly@*/
pw->pw_gecos = strdup (pwent->pw_gecos);
/*@=mustfreeonly@*/
if (NULL == pw->pw_gecos) {
pw_free(pw);
return NULL;
}
/*@-mustfreeonly@*/
pw->pw_dir = strdup (pwent->pw_dir);
/*@=mustfreeonly@*/
if (NULL == pw->pw_dir) {
pw_free(pw);
return NULL;
}
/*@-mustfreeonly@*/
pw->pw_shell = strdup (pwent->pw_shell);
/*@=mustfreeonly@*/
if (NULL == pw->pw_shell) {
pw_free(pw);
return NULL;
}
return pw;
}
void pw_free (/*@out@*/ /*@only@*/struct passwd *pwent)
{
if (pwent != NULL) {
free (pwent->pw_name);
if (pwent->pw_passwd) {
memzero (pwent->pw_passwd, strlen (pwent->pw_passwd));
free (pwent->pw_passwd);
}
free (pwent->pw_gecos);
free (pwent->pw_dir);
free (pwent->pw_shell);
free (pwent);
}
}