209 lines · c
1// SPDX-License-Identifier: GPL-2.02#define _GNU_SOURCE3#include <test_progs.h>4#include <sys/stat.h>5#include <linux/sched.h>6#include <sys/syscall.h>7 8#define MAX_PATH_LEN 1289#define MAX_FILES 710 11#include "test_d_path.skel.h"12#include "test_d_path_check_rdonly_mem.skel.h"13#include "test_d_path_check_types.skel.h"14 15/* sys_close_range is not around for long time, so let's16 * make sure we can call it on systems with older glibc17 */18#ifndef __NR_close_range19#ifdef __alpha__20#define __NR_close_range 54621#else22#define __NR_close_range 43623#endif24#endif25 26static int duration;27 28static struct {29 __u32 cnt;30 char paths[MAX_FILES][MAX_PATH_LEN];31} src;32 33static int set_pathname(int fd, pid_t pid)34{35 char buf[MAX_PATH_LEN];36 37 snprintf(buf, MAX_PATH_LEN, "/proc/%d/fd/%d", pid, fd);38 return readlink(buf, src.paths[src.cnt++], MAX_PATH_LEN);39}40 41static int trigger_fstat_events(pid_t pid)42{43 int sockfd = -1, procfd = -1, devfd = -1;44 int localfd = -1, indicatorfd = -1;45 int pipefd[2] = { -1, -1 };46 struct stat fileStat;47 int ret = -1;48 49 /* unmountable pseudo-filesystems */50 if (CHECK(pipe(pipefd) < 0, "trigger", "pipe failed\n"))51 return ret;52 /* unmountable pseudo-filesystems */53 sockfd = socket(AF_INET, SOCK_STREAM, 0);54 if (CHECK(sockfd < 0, "trigger", "socket failed\n"))55 goto out_close;56 /* mountable pseudo-filesystems */57 procfd = open("/proc/self/comm", O_RDONLY);58 if (CHECK(procfd < 0, "trigger", "open /proc/self/comm failed\n"))59 goto out_close;60 devfd = open("/dev/urandom", O_RDONLY);61 if (CHECK(devfd < 0, "trigger", "open /dev/urandom failed\n"))62 goto out_close;63 localfd = open("/tmp/d_path_loadgen.txt", O_CREAT | O_RDONLY, 0644);64 if (CHECK(localfd < 0, "trigger", "open /tmp/d_path_loadgen.txt failed\n"))65 goto out_close;66 /* bpf_d_path will return path with (deleted) */67 remove("/tmp/d_path_loadgen.txt");68 indicatorfd = open("/tmp/", O_PATH);69 if (CHECK(indicatorfd < 0, "trigger", "open /tmp/ failed\n"))70 goto out_close;71 72 ret = set_pathname(pipefd[0], pid);73 if (CHECK(ret < 0, "trigger", "set_pathname failed for pipe[0]\n"))74 goto out_close;75 ret = set_pathname(pipefd[1], pid);76 if (CHECK(ret < 0, "trigger", "set_pathname failed for pipe[1]\n"))77 goto out_close;78 ret = set_pathname(sockfd, pid);79 if (CHECK(ret < 0, "trigger", "set_pathname failed for socket\n"))80 goto out_close;81 ret = set_pathname(procfd, pid);82 if (CHECK(ret < 0, "trigger", "set_pathname failed for proc\n"))83 goto out_close;84 ret = set_pathname(devfd, pid);85 if (CHECK(ret < 0, "trigger", "set_pathname failed for dev\n"))86 goto out_close;87 ret = set_pathname(localfd, pid);88 if (CHECK(ret < 0, "trigger", "set_pathname failed for file\n"))89 goto out_close;90 ret = set_pathname(indicatorfd, pid);91 if (CHECK(ret < 0, "trigger", "set_pathname failed for dir\n"))92 goto out_close;93 94 /* triggers vfs_getattr */95 fstat(pipefd[0], &fileStat);96 fstat(pipefd[1], &fileStat);97 fstat(sockfd, &fileStat);98 fstat(procfd, &fileStat);99 fstat(devfd, &fileStat);100 fstat(localfd, &fileStat);101 fstat(indicatorfd, &fileStat);102 103out_close:104 /* sys_close no longer triggers filp_close, but we can105 * call sys_close_range instead which still does106 */107#define close(fd) syscall(__NR_close_range, fd, fd, 0)108 109 close(pipefd[0]);110 close(pipefd[1]);111 close(sockfd);112 close(procfd);113 close(devfd);114 close(localfd);115 close(indicatorfd);116 117#undef close118 return ret;119}120 121static void test_d_path_basic(void)122{123 struct test_d_path__bss *bss;124 struct test_d_path *skel;125 int err;126 127 skel = test_d_path__open_and_load();128 if (CHECK(!skel, "setup", "d_path skeleton failed\n"))129 goto cleanup;130 131 err = test_d_path__attach(skel);132 if (CHECK(err, "setup", "attach failed: %d\n", err))133 goto cleanup;134 135 bss = skel->bss;136 bss->my_pid = getpid();137 138 err = trigger_fstat_events(bss->my_pid);139 if (err < 0)140 goto cleanup;141 142 if (CHECK(!bss->called_stat,143 "stat",144 "trampoline for security_inode_getattr was not called\n"))145 goto cleanup;146 147 if (CHECK(!bss->called_close,148 "close",149 "trampoline for filp_close was not called\n"))150 goto cleanup;151 152 for (int i = 0; i < MAX_FILES; i++) {153 CHECK(strncmp(src.paths[i], bss->paths_stat[i], MAX_PATH_LEN),154 "check",155 "failed to get stat path[%d]: %s vs %s\n",156 i, src.paths[i], bss->paths_stat[i]);157 CHECK(strncmp(src.paths[i], bss->paths_close[i], MAX_PATH_LEN),158 "check",159 "failed to get close path[%d]: %s vs %s\n",160 i, src.paths[i], bss->paths_close[i]);161 /* The d_path helper returns size plus NUL char, hence + 1 */162 CHECK(bss->rets_stat[i] != strlen(bss->paths_stat[i]) + 1,163 "check",164 "failed to match stat return [%d]: %d vs %zd [%s]\n",165 i, bss->rets_stat[i], strlen(bss->paths_stat[i]) + 1,166 bss->paths_stat[i]);167 CHECK(bss->rets_close[i] != strlen(bss->paths_stat[i]) + 1,168 "check",169 "failed to match stat return [%d]: %d vs %zd [%s]\n",170 i, bss->rets_close[i], strlen(bss->paths_close[i]) + 1,171 bss->paths_stat[i]);172 }173 174cleanup:175 test_d_path__destroy(skel);176}177 178static void test_d_path_check_rdonly_mem(void)179{180 struct test_d_path_check_rdonly_mem *skel;181 182 skel = test_d_path_check_rdonly_mem__open_and_load();183 ASSERT_ERR_PTR(skel, "unexpected_load_overwriting_rdonly_mem");184 185 test_d_path_check_rdonly_mem__destroy(skel);186}187 188static void test_d_path_check_types(void)189{190 struct test_d_path_check_types *skel;191 192 skel = test_d_path_check_types__open_and_load();193 ASSERT_ERR_PTR(skel, "unexpected_load_passing_wrong_type");194 195 test_d_path_check_types__destroy(skel);196}197 198void test_d_path(void)199{200 if (test__start_subtest("basic"))201 test_d_path_basic();202 203 if (test__start_subtest("check_rdonly_mem"))204 test_d_path_check_rdonly_mem();205 206 if (test__start_subtest("check_alloc_mem"))207 test_d_path_check_types();208}209