1*8d741a5dSApple OSS Distributions /*
2*8d741a5dSApple OSS Distributions * Copyright (c) 2021 Apple Inc. All rights reserved.
3*8d741a5dSApple OSS Distributions *
4*8d741a5dSApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*8d741a5dSApple OSS Distributions *
6*8d741a5dSApple OSS Distributions * This file contains Original Code and/or Modifications of Original Code
7*8d741a5dSApple OSS Distributions * as defined in and that are subject to the Apple Public Source License
8*8d741a5dSApple OSS Distributions * Version 2.0 (the 'License'). You may not use this file except in
9*8d741a5dSApple OSS Distributions * compliance with the License. The rights granted to you under the License
10*8d741a5dSApple OSS Distributions * may not be used to create, or enable the creation or redistribution of,
11*8d741a5dSApple OSS Distributions * unlawful or unlicensed copies of an Apple operating system, or to
12*8d741a5dSApple OSS Distributions * circumvent, violate, or enable the circumvention or violation of, any
13*8d741a5dSApple OSS Distributions * terms of an Apple operating system software license agreement.
14*8d741a5dSApple OSS Distributions *
15*8d741a5dSApple OSS Distributions * Please obtain a copy of the License at
16*8d741a5dSApple OSS Distributions * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*8d741a5dSApple OSS Distributions *
18*8d741a5dSApple OSS Distributions * The Original Code and all software distributed under the License are
19*8d741a5dSApple OSS Distributions * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*8d741a5dSApple OSS Distributions * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*8d741a5dSApple OSS Distributions * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*8d741a5dSApple OSS Distributions * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*8d741a5dSApple OSS Distributions * Please see the License for the specific language governing rights and
24*8d741a5dSApple OSS Distributions * limitations under the License.
25*8d741a5dSApple OSS Distributions *
26*8d741a5dSApple OSS Distributions * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*8d741a5dSApple OSS Distributions */
28*8d741a5dSApple OSS Distributions
29*8d741a5dSApple OSS Distributions #if (DEVELOPMENT || DEBUG) && !KASAN
30*8d741a5dSApple OSS Distributions
31*8d741a5dSApple OSS Distributions #include <sys/sysctl.h>
32*8d741a5dSApple OSS Distributions #include <libkern/stack_protector.h>
33*8d741a5dSApple OSS Distributions
34*8d741a5dSApple OSS Distributions __attribute__((noinline))
35*8d741a5dSApple OSS Distributions static int
check_for_cookie(size_t len)36*8d741a5dSApple OSS Distributions check_for_cookie(size_t len)
37*8d741a5dSApple OSS Distributions {
38*8d741a5dSApple OSS Distributions long buf[4];
39*8d741a5dSApple OSS Distributions long *search = (long *)(void *)&buf[0];
40*8d741a5dSApple OSS Distributions size_t n;
41*8d741a5dSApple OSS Distributions
42*8d741a5dSApple OSS Distributions assert(len < sizeof(buf));
43*8d741a5dSApple OSS Distributions assert(__stack_chk_guard != 0);
44*8d741a5dSApple OSS Distributions assert(((uintptr_t)search & (sizeof(long) - 1)) == 0);
45*8d741a5dSApple OSS Distributions
46*8d741a5dSApple OSS Distributions /* force compiler to insert stack cookie check: */
47*8d741a5dSApple OSS Distributions memset_s(buf, len, 0, len);
48*8d741a5dSApple OSS Distributions
49*8d741a5dSApple OSS Distributions /* 32 x sizeof(long) should be plenty to find the cookie: */
50*8d741a5dSApple OSS Distributions for (n = 0; n < 32; ++n) {
51*8d741a5dSApple OSS Distributions if (*(search++) == __stack_chk_guard) {
52*8d741a5dSApple OSS Distributions return 0;
53*8d741a5dSApple OSS Distributions }
54*8d741a5dSApple OSS Distributions }
55*8d741a5dSApple OSS Distributions
56*8d741a5dSApple OSS Distributions return ESRCH;
57*8d741a5dSApple OSS Distributions }
58*8d741a5dSApple OSS Distributions
59*8d741a5dSApple OSS Distributions static int
60*8d741a5dSApple OSS Distributions sysctl_run_stack_chk_tests SYSCTL_HANDLER_ARGS
61*8d741a5dSApple OSS Distributions {
62*8d741a5dSApple OSS Distributions #pragma unused(arg1, arg2, oidp)
63*8d741a5dSApple OSS Distributions
64*8d741a5dSApple OSS Distributions unsigned int dummy = 0;
65*8d741a5dSApple OSS Distributions int error, changed = 0, kr;
66*8d741a5dSApple OSS Distributions error = sysctl_io_number(req, 0, sizeof(dummy), &dummy, &changed);
67*8d741a5dSApple OSS Distributions if (error || !changed) {
68*8d741a5dSApple OSS Distributions return error;
69*8d741a5dSApple OSS Distributions }
70*8d741a5dSApple OSS Distributions
71*8d741a5dSApple OSS Distributions kr = check_for_cookie(3);
72*8d741a5dSApple OSS Distributions return kr;
73*8d741a5dSApple OSS Distributions }
74*8d741a5dSApple OSS Distributions
75*8d741a5dSApple OSS Distributions SYSCTL_PROC(_kern, OID_AUTO, run_stack_chk_tests,
76*8d741a5dSApple OSS Distributions CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED | CTLFLAG_MASKED,
77*8d741a5dSApple OSS Distributions 0, 0, sysctl_run_stack_chk_tests, "I", "");
78*8d741a5dSApple OSS Distributions
79*8d741a5dSApple OSS Distributions #endif /* (DEVELOPMENT || DEBUG) && !KASAN */
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