1*3bf301e1SKees Cook // SPDX-License-Identifier: GPL-2.0
2*3bf301e1SKees Cook /*
3*3bf301e1SKees Cook * Kernel module for testing 'strcat' family of functions.
4*3bf301e1SKees Cook */
5*3bf301e1SKees Cook
6*3bf301e1SKees Cook #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7*3bf301e1SKees Cook
8*3bf301e1SKees Cook #include <kunit/test.h>
9*3bf301e1SKees Cook #include <linux/string.h>
10*3bf301e1SKees Cook
11*3bf301e1SKees Cook static volatile int unconst;
12*3bf301e1SKees Cook
strcat_test(struct kunit * test)13*3bf301e1SKees Cook static void strcat_test(struct kunit *test)
14*3bf301e1SKees Cook {
15*3bf301e1SKees Cook char dest[8];
16*3bf301e1SKees Cook
17*3bf301e1SKees Cook /* Destination is terminated. */
18*3bf301e1SKees Cook memset(dest, 0, sizeof(dest));
19*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlen(dest), 0);
20*3bf301e1SKees Cook /* Empty copy does nothing. */
21*3bf301e1SKees Cook KUNIT_EXPECT_TRUE(test, strcat(dest, "") == dest);
22*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "");
23*3bf301e1SKees Cook /* 4 characters copied in, stops at %NUL. */
24*3bf301e1SKees Cook KUNIT_EXPECT_TRUE(test, strcat(dest, "four\000123") == dest);
25*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "four");
26*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, dest[5], '\0');
27*3bf301e1SKees Cook /* 2 more characters copied in okay. */
28*3bf301e1SKees Cook KUNIT_EXPECT_TRUE(test, strcat(dest, "AB") == dest);
29*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "fourAB");
30*3bf301e1SKees Cook }
31*3bf301e1SKees Cook
strncat_test(struct kunit * test)32*3bf301e1SKees Cook static void strncat_test(struct kunit *test)
33*3bf301e1SKees Cook {
34*3bf301e1SKees Cook char dest[8];
35*3bf301e1SKees Cook
36*3bf301e1SKees Cook /* Destination is terminated. */
37*3bf301e1SKees Cook memset(dest, 0, sizeof(dest));
38*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlen(dest), 0);
39*3bf301e1SKees Cook /* Empty copy of size 0 does nothing. */
40*3bf301e1SKees Cook KUNIT_EXPECT_TRUE(test, strncat(dest, "", 0 + unconst) == dest);
41*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "");
42*3bf301e1SKees Cook /* Empty copy of size 1 does nothing too. */
43*3bf301e1SKees Cook KUNIT_EXPECT_TRUE(test, strncat(dest, "", 1 + unconst) == dest);
44*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "");
45*3bf301e1SKees Cook /* Copy of max 0 characters should do nothing. */
46*3bf301e1SKees Cook KUNIT_EXPECT_TRUE(test, strncat(dest, "asdf", 0 + unconst) == dest);
47*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "");
48*3bf301e1SKees Cook
49*3bf301e1SKees Cook /* 4 characters copied in, even if max is 8. */
50*3bf301e1SKees Cook KUNIT_EXPECT_TRUE(test, strncat(dest, "four\000123", 8 + unconst) == dest);
51*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "four");
52*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, dest[5], '\0');
53*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, dest[6], '\0');
54*3bf301e1SKees Cook /* 2 characters copied in okay, 2 ignored. */
55*3bf301e1SKees Cook KUNIT_EXPECT_TRUE(test, strncat(dest, "ABCD", 2 + unconst) == dest);
56*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "fourAB");
57*3bf301e1SKees Cook }
58*3bf301e1SKees Cook
strlcat_test(struct kunit * test)59*3bf301e1SKees Cook static void strlcat_test(struct kunit *test)
60*3bf301e1SKees Cook {
61*3bf301e1SKees Cook char dest[8] = "";
62*3bf301e1SKees Cook int len = sizeof(dest) + unconst;
63*3bf301e1SKees Cook
64*3bf301e1SKees Cook /* Destination is terminated. */
65*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlen(dest), 0);
66*3bf301e1SKees Cook /* Empty copy is size 0. */
67*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlcat(dest, "", len), 0);
68*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "");
69*3bf301e1SKees Cook /* Size 1 should keep buffer terminated, report size of source only. */
70*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlcat(dest, "four", 1 + unconst), 4);
71*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "");
72*3bf301e1SKees Cook
73*3bf301e1SKees Cook /* 4 characters copied in. */
74*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlcat(dest, "four", len), 4);
75*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "four");
76*3bf301e1SKees Cook /* 2 characters copied in okay, gets to 6 total. */
77*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlcat(dest, "AB", len), 6);
78*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "fourAB");
79*3bf301e1SKees Cook /* 2 characters ignored if max size (7) reached. */
80*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlcat(dest, "CD", 7 + unconst), 8);
81*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "fourAB");
82*3bf301e1SKees Cook /* 1 of 2 characters skipped, now at true max size. */
83*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlcat(dest, "EFG", len), 9);
84*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "fourABE");
85*3bf301e1SKees Cook /* Everything else ignored, now at full size. */
86*3bf301e1SKees Cook KUNIT_EXPECT_EQ(test, strlcat(dest, "1234", len), 11);
87*3bf301e1SKees Cook KUNIT_EXPECT_STREQ(test, dest, "fourABE");
88*3bf301e1SKees Cook }
89*3bf301e1SKees Cook
90*3bf301e1SKees Cook static struct kunit_case strcat_test_cases[] = {
91*3bf301e1SKees Cook KUNIT_CASE(strcat_test),
92*3bf301e1SKees Cook KUNIT_CASE(strncat_test),
93*3bf301e1SKees Cook KUNIT_CASE(strlcat_test),
94*3bf301e1SKees Cook {}
95*3bf301e1SKees Cook };
96*3bf301e1SKees Cook
97*3bf301e1SKees Cook static struct kunit_suite strcat_test_suite = {
98*3bf301e1SKees Cook .name = "strcat",
99*3bf301e1SKees Cook .test_cases = strcat_test_cases,
100*3bf301e1SKees Cook };
101*3bf301e1SKees Cook
102*3bf301e1SKees Cook kunit_test_suite(strcat_test_suite);
103*3bf301e1SKees Cook
104*3bf301e1SKees Cook MODULE_LICENSE("GPL");
105