1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * This test covers the anonymous VMA naming functionality through prctl calls
4 */
5
6 #include <errno.h>
7 #include <sys/prctl.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <sys/mman.h>
11 #include <string.h>
12
13 #include "../kselftest_harness.h"
14
15 #define AREA_SIZE 1024
16
17 #define GOOD_NAME "goodname"
18 #define BAD_NAME "badname\1"
19
20 #ifndef PR_SET_VMA
21 #define PR_SET_VMA 0x53564d41
22 #define PR_SET_VMA_ANON_NAME 0
23 #endif
24
25
26 int rename_vma(unsigned long addr, unsigned long size, char *name)
27 {
28 int res;
29
30 res = prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, addr, size, name);
31 if (res < 0)
32 return -errno;
33 return res;
34 }
35
36 int was_renaming_successful(char *target_name, unsigned long ptr)
37 {
38 FILE *maps_file;
39
40 char line_buf[512], name[128], mode[8];
41 unsigned long start_addr, end_addr, offset;
42 unsigned int major_id, minor_id, node_id;
43
44 char target_buf[128];
45 int res = 0, sscanf_res;
46
47 // The entry name in maps will be in format [anon:<target_name>]
48 sprintf(target_buf, "[anon:%s]", target_name);
49 maps_file = fopen("/proc/self/maps", "r");
50 if (!maps_file) {
51 printf("## /proc/self/maps file opening error\n");
52 return 0;
53 }
54
55 // Parse the maps file to find the entry we renamed
56 while (fgets(line_buf, sizeof(line_buf), maps_file)) {
57 sscanf_res = sscanf(line_buf, "%lx-%lx %7s %lx %u:%u %u %s", &start_addr,
58 &end_addr, mode, &offset, &major_id,
59 &minor_id, &node_id, name);
60 if (sscanf_res == EOF) {
61 res = 0;
62 printf("## EOF while parsing the maps file\n");
63 break;
64 }
65 if (!strcmp(name, target_buf) && start_addr == ptr) {
66 res = 1;
67 break;
68 }
69 }
70 fclose(maps_file);
71 return res;
72 }
73
74 FIXTURE(vma) {
75 void *ptr_anon, *ptr_not_anon;
76 };
77
78 FIXTURE_SETUP(vma) {
79 self->ptr_anon = mmap(NULL, AREA_SIZE, PROT_READ | PROT_WRITE,
80 MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
81 ASSERT_NE(self->ptr_anon, NULL);
82 self->ptr_not_anon = mmap(NULL, AREA_SIZE, PROT_READ | PROT_WRITE,
83 MAP_PRIVATE, 0, 0);
84 ASSERT_NE(self->ptr_not_anon, NULL);
85 }
86
87 FIXTURE_TEARDOWN(vma) {
88 munmap(self->ptr_anon, AREA_SIZE);
89 munmap(self->ptr_not_anon, AREA_SIZE);
90 }
91
92 TEST_F(vma, renaming) {
93 TH_LOG("Try to rename the VMA with correct parameters");
94 EXPECT_GE(rename_vma((unsigned long)self->ptr_anon, AREA_SIZE, GOOD_NAME), 0);
95 EXPECT_TRUE(was_renaming_successful(GOOD_NAME, (unsigned long)self->ptr_anon));
96
97 TH_LOG("Try to pass invalid name (with non-printable character \\1) to rename the VMA");
98 EXPECT_EQ(rename_vma((unsigned long)self->ptr_anon, AREA_SIZE, BAD_NAME), -EINVAL);
99
100 TH_LOG("Try to rename non-anonymous VMA");
101 EXPECT_EQ(rename_vma((unsigned long) self->ptr_not_anon, AREA_SIZE, GOOD_NAME), -EINVAL);
102 }
103
104 TEST_HARNESS_MAIN
105
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