freebsd-src/lib/libc/posix1e/acl_equiv_mode_np.c
Brooks Davis 85c9d36497 acl_equiv_mode_np: zero mode on just inited ACL
You can't return 0 and not write the mode if mode_p is non-NULL.  That
violates the API contract and in common usage leaves stack trash in
*mode_p.

The acl_equiv_mode_test test passed by accident.

Reviewed by:	kevans, markj
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D43278
2024-01-03 16:34:39 +00:00

100 lines
2.9 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2021 Gleb Popov
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
/*
* acl_equiv_mode_np: Check if an ACL can be represented as a mode_t.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/acl.h>
#include "acl_support.h"
int
acl_equiv_mode_np(acl_t acl, mode_t *mode_p)
{
mode_t ret_mode = 0;
if (acl == NULL) {
errno = EINVAL;
return (-1);
}
/* Linux returns 0 for ACL returned by acl_init() */
if (_acl_brand(acl) == ACL_BRAND_UNKNOWN && acl->ats_acl.acl_cnt == 0)
goto done;
// TODO: Do we want to handle ACL_BRAND_NFS4 in this function? */
if (_acl_brand(acl) != ACL_BRAND_POSIX)
return (1);
for (int cur_entry = 0; cur_entry < acl->ats_acl.acl_cnt; cur_entry++) {
acl_entry_t entry = &acl->ats_acl.acl_entry[cur_entry];
if ((entry->ae_perm & ACL_PERM_BITS) != entry->ae_perm)
return (1);
switch (entry->ae_tag) {
case ACL_USER_OBJ:
if (entry->ae_perm & ACL_READ)
ret_mode |= S_IRUSR;
if (entry->ae_perm & ACL_WRITE)
ret_mode |= S_IWUSR;
if (entry->ae_perm & ACL_EXECUTE)
ret_mode |= S_IXUSR;
break;
case ACL_GROUP_OBJ:
if (entry->ae_perm & ACL_READ)
ret_mode |= S_IRGRP;
if (entry->ae_perm & ACL_WRITE)
ret_mode |= S_IWGRP;
if (entry->ae_perm & ACL_EXECUTE)
ret_mode |= S_IXGRP;
break;
case ACL_OTHER:
if (entry->ae_perm & ACL_READ)
ret_mode |= S_IROTH;
if (entry->ae_perm & ACL_WRITE)
ret_mode |= S_IWOTH;
if (entry->ae_perm & ACL_EXECUTE)
ret_mode |= S_IXOTH;
break;
default:
return (1);
}
}
done:
if (mode_p != NULL)
*mode_p = ret_mode;
return (0);
}