10076 make usr/src/test smatch clean
1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright 2018 Joyent, Inc.
14 */
15
16 #include <stdlib.h>
17 #include <ucontext.h>
18 #include <sys/wait.h>
19 #include <unistd.h>
20 #include <sys/regset.h>
21
22 /*
23 * Load a bunch of bad selectors into the seg regs: this will typically cause
24 * the child process to core dump, but it shouldn't panic the kernel...
25 *
26 * It's especially interesting to run this on CPU0.
27 */
28
29 unsigned short selector;
30
31 static void badds(void)
32 {
33 __asm__ volatile("movw %0, %%ds" : : "r" (selector));
34 }
35
36 static void bades(void)
37 {
38 __asm__ volatile("movw %0, %%es" : : "r" (selector));
39 }
40
41 static void badfs(void)
42 {
43 __asm__ volatile("movw %0, %%fs" : : "r" (selector));
44 }
45
46 static void badgs(void)
47 {
48 __asm__ volatile("movw %0, %%gs" : : "r" (selector));
49 }
50
51 static void badss(void)
52 {
53 __asm__ volatile("movw %0, %%ss" : : "r" (selector));
54 }
55
56 static void
57 resetseg(uint_t seg)
58 {
59 ucontext_t ucp;
60 volatile int done = 0;
61
62 int rc = getcontext(&ucp);
63 if (done) {
64 (void) getcontext(&ucp);
65 return;
66 }
67
68 if (rc == 0) {
69 done = 1;
70 ucp.uc_mcontext.gregs[seg] = selector;
71 setcontext(&ucp);
72 }
73 abort();
74 }
75
76 static void
77 resetcs(void)
78 {
79 return (resetseg(CS));
80 }
81
82 static void
83 resetds(void)
84 {
85 return (resetseg(DS));
86 }
87
88 static void
89 resetes(void)
90 {
91 return (resetseg(ES));
92 }
93
94 static void
95 resetfs(void)
96 {
97 return (resetseg(FS));
98 }
99
100 static void
101 resetgs(void)
102 {
103 return (resetseg(GS));
104 }
105
106 static void
107 resetss(void)
108 {
109 return (resetseg(SS));
110 }
111
112 static void
113 inchild(void (*func)())
114 {
115 pid_t pid;
116
117 switch ((pid = fork())) {
118 case 0:
119 func();
120 exit(0);
121 case -1:
122 exit(1);
123 default:
124 (void) waitpid(pid, NULL, 0);
125 return;
126 }
127
128 }
129
130 int
131 main(int argc, char *argv[])
132 {
133 for (selector = 0; selector < 8194; selector++) {
134 inchild(resetcs);
135 inchild(resetds);
136 inchild(resetes);
137 inchild(resetfs);
138 inchild(resetgs);
139 inchild(resetss);
140 inchild(badds);
141 inchild(bades);
142 inchild(badfs);
143 inchild(badgs);
144 inchild(badss);
145 }
146
147 exit(0);
148 }
--- EOF ---