diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/test_lsm.c')
-rw-r--r-- | tools/testing/selftests/bpf/prog_tests/test_lsm.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/test_lsm.c b/tools/testing/selftests/bpf/prog_tests/test_lsm.c new file mode 100644 index 000000000..244c01125 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/test_lsm.c @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright (C) 2020 Google LLC. + */ + +#include <test_progs.h> +#include <sys/mman.h> +#include <sys/wait.h> +#include <unistd.h> +#include <malloc.h> +#include <stdlib.h> + +#include "lsm.skel.h" + +char *CMD_ARGS[] = {"true", NULL}; + +#define GET_PAGE_ADDR(ADDR, PAGE_SIZE) \ + (char *)(((unsigned long) (ADDR + PAGE_SIZE)) & ~(PAGE_SIZE-1)) + +int stack_mprotect(void) +{ + void *buf; + long sz; + int ret; + + sz = sysconf(_SC_PAGESIZE); + if (sz < 0) + return sz; + + buf = alloca(sz * 3); + ret = mprotect(GET_PAGE_ADDR(buf, sz), sz, + PROT_READ | PROT_WRITE | PROT_EXEC); + return ret; +} + +int exec_cmd(int *monitored_pid) +{ + int child_pid, child_status; + + child_pid = fork(); + if (child_pid == 0) { + *monitored_pid = getpid(); + execvp(CMD_ARGS[0], CMD_ARGS); + return -EINVAL; + } else if (child_pid > 0) { + waitpid(child_pid, &child_status, 0); + return child_status; + } + + return -EINVAL; +} + +static int test_lsm(struct lsm *skel) +{ + struct bpf_link *link; + int buf = 1234; + int err; + + err = lsm__attach(skel); + if (!ASSERT_OK(err, "attach")) + return err; + + /* Check that already linked program can't be attached again. */ + link = bpf_program__attach(skel->progs.test_int_hook); + if (!ASSERT_ERR_PTR(link, "attach_link")) + return -1; + + err = exec_cmd(&skel->bss->monitored_pid); + if (!ASSERT_OK(err, "exec_cmd")) + return err; + + ASSERT_EQ(skel->bss->bprm_count, 1, "bprm_count"); + + skel->bss->monitored_pid = getpid(); + + err = stack_mprotect(); + if (!ASSERT_EQ(errno, EPERM, "stack_mprotect")) + return err; + + ASSERT_EQ(skel->bss->mprotect_count, 1, "mprotect_count"); + + syscall(__NR_setdomainname, &buf, -2L); + syscall(__NR_setdomainname, 0, -3L); + syscall(__NR_setdomainname, ~0L, -4L); + + ASSERT_EQ(skel->bss->copy_test, 3, "copy_test"); + + lsm__detach(skel); + + skel->bss->copy_test = 0; + skel->bss->bprm_count = 0; + skel->bss->mprotect_count = 0; + return 0; +} + +void test_test_lsm(void) +{ + struct lsm *skel = NULL; + int err; + + skel = lsm__open_and_load(); + if (!ASSERT_OK_PTR(skel, "lsm_skel_load")) + goto close_prog; + + err = test_lsm(skel); + if (!ASSERT_OK(err, "test_lsm_first_attach")) + goto close_prog; + + err = test_lsm(skel); + ASSERT_OK(err, "test_lsm_second_attach"); + +close_prog: + lsm__destroy(skel); +} |