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