1 #include <linux/kernel.h>
2 
3 #include "opcode.h"
4 #include "selftest.h"
5 
6 struct selftest_opcode {
7 	unsigned int expected_size;
8 	const uint8_t *insn;
9 	const char *desc;
10 };
11 
12 static const struct selftest_opcode selftest_opcodes[] = {
13 	/* REP MOVS */
14 	{1, "\xf3\xa4", 		"rep movsb <mem8>, <mem8>"},
15 	{4, "\xf3\xa5",			"rep movsl <mem32>, <mem32>"},
16 
17 	/* MOVZX / MOVZXD */
18 	{1, "\x66\x0f\xb6\x51\xf8",	"movzwq <mem8>, <reg16>"},
19 	{1, "\x0f\xb6\x51\xf8",		"movzwq <mem8>, <reg32>"},
20 
21 	/* MOVSX / MOVSXD */
22 	{1, "\x66\x0f\xbe\x51\xf8",	"movswq <mem8>, <reg16>"},
23 	{1, "\x0f\xbe\x51\xf8",		"movswq <mem8>, <reg32>"},
24 
25 #ifdef CONFIG_X86_64
26 	/* MOVZX / MOVZXD */
27 	{1, "\x49\x0f\xb6\x51\xf8",	"movzbq <mem8>, <reg64>"},
28 	{2, "\x49\x0f\xb7\x51\xf8",	"movzbq <mem16>, <reg64>"},
29 
30 	/* MOVSX / MOVSXD */
31 	{1, "\x49\x0f\xbe\x51\xf8",	"movsbq <mem8>, <reg64>"},
32 	{2, "\x49\x0f\xbf\x51\xf8",	"movsbq <mem16>, <reg64>"},
33 	{4, "\x49\x63\x51\xf8",		"movslq <mem32>, <reg64>"},
34 #endif
35 };
36 
selftest_opcode_one(const struct selftest_opcode * op)37 static bool selftest_opcode_one(const struct selftest_opcode *op)
38 {
39 	unsigned size;
40 
41 	kmemcheck_opcode_decode(op->insn, &size);
42 
43 	if (size == op->expected_size)
44 		return true;
45 
46 	printk(KERN_WARNING "kmemcheck: opcode %s: expected size %d, got %d\n",
47 		op->desc, op->expected_size, size);
48 	return false;
49 }
50 
selftest_opcodes_all(void)51 static bool selftest_opcodes_all(void)
52 {
53 	bool pass = true;
54 	unsigned int i;
55 
56 	for (i = 0; i < ARRAY_SIZE(selftest_opcodes); ++i)
57 		pass = pass && selftest_opcode_one(&selftest_opcodes[i]);
58 
59 	return pass;
60 }
61 
kmemcheck_selftest(void)62 bool kmemcheck_selftest(void)
63 {
64 	bool pass = true;
65 
66 	pass = pass && selftest_opcodes_all();
67 
68 	return pass;
69 }
70