diff options
4 files changed, 212 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/string_kfuncs.c b/tools/testing/selftests/bpf/prog_tests/string_kfuncs.c new file mode 100644 index 000000000000..35af8044d059 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/string_kfuncs.c @@ -0,0 +1,65 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2025 Red Hat, Inc.*/ +#include <test_progs.h> +#include "string_kfuncs_success.skel.h" +#include "string_kfuncs_failure1.skel.h" +#include "string_kfuncs_failure2.skel.h" +#include <sys/mman.h> + +static const char * const test_cases[] = { + "strcmp", + "strchr", + "strchrnul", + "strnchr", + "strrchr", + "strlen", + "strnlen", + "strspn_str", + "strspn_accept", + "strcspn_str", + "strcspn_reject", + "strstr", + "strnstr", +}; + +void run_too_long_tests(void) +{ + struct string_kfuncs_failure2 *skel; + struct bpf_program *prog; + char test_name[256]; + int err, i; + + skel = string_kfuncs_failure2__open_and_load(); + if (!ASSERT_OK_PTR(skel, "string_kfuncs_failure2__open_and_load")) + return; + + memset(skel->bss->long_str, 'a', sizeof(skel->bss->long_str)); + + for (i = 0; i < ARRAY_SIZE(test_cases); i++) { + sprintf(test_name, "test_%s_too_long", test_cases[i]); + if (!test__start_subtest(test_name)) + continue; + + prog = bpf_object__find_program_by_name(skel->obj, test_name); + if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name")) + goto cleanup; + + LIBBPF_OPTS(bpf_test_run_opts, topts); + err = bpf_prog_test_run_opts(bpf_program__fd(prog), &topts); + if (!ASSERT_OK(err, "bpf_prog_test_run")) + goto cleanup; + + ASSERT_EQ(topts.retval, -E2BIG, "reading too long string fails with -E2BIG"); + } + +cleanup: + string_kfuncs_failure2__destroy(skel); +} + +void test_string_kfuncs(void) +{ + RUN_TESTS(string_kfuncs_success); + RUN_TESTS(string_kfuncs_failure1); + + run_too_long_tests(); +} diff --git a/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c b/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c new file mode 100644 index 000000000000..53af438bd998 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/string_kfuncs_failure1.c @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2025 Red Hat, Inc.*/ +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include <linux/limits.h> +#include "bpf_misc.h" +#include "errno.h" + +char *user_ptr = (char *)1; +char *invalid_kern_ptr = (char *)-1; + +/* + * When passing userspace pointers, the error code differs based on arch: + * -ERANGE on arches with non-overlapping address spaces + * -EFAULT on other arches + */ +#if defined(__TARGET_ARCH_arm) || defined(__TARGET_ARCH_loongarch) || \ + defined(__TARGET_ARCH_powerpc) || defined(__TARGET_ARCH_x86) +#define USER_PTR_ERR -ERANGE +#else +#define USER_PTR_ERR -EFAULT +#endif + +/* + * On s390, __get_kernel_nofault (used in string kfuncs) returns 0 for NULL and + * user_ptr (instead of causing an exception) so the below two groups of tests + * are not applicable. + */ +#ifndef __TARGET_ARCH_s390 + +/* Passing NULL to string kfuncs (treated as a userspace ptr) */ +SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_null1(void *ctx) { return bpf_strcmp(NULL, "hello"); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strcmp_null2(void *ctx) { return bpf_strcmp("hello", NULL); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strchr_null(void *ctx) { return bpf_strchr(NULL, 'a'); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strchrnul_null(void *ctx) { return bpf_strchrnul(NULL, 'a'); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strnchr_null(void *ctx) { return bpf_strnchr(NULL, 1, 'a'); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strrchr_null(void *ctx) { return bpf_strrchr(NULL, 'a'); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strlen_null(void *ctx) { return bpf_strlen(NULL); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strnlen_null(void *ctx) { return bpf_strnlen(NULL, 1); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strspn_null1(void *ctx) { return bpf_strspn(NULL, "hello"); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strspn_null2(void *ctx) { return bpf_strspn("hello", NULL); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strcspn_null1(void *ctx) { return bpf_strcspn(NULL, "hello"); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strcspn_null2(void *ctx) { return bpf_strcspn("hello", NULL); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strstr_null1(void *ctx) { return bpf_strstr(NULL, "hello"); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strstr_null2(void *ctx) { return bpf_strstr("hello", NULL); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strnstr_null1(void *ctx) { return bpf_strnstr(NULL, "hello", 1); } +SEC("syscall") __retval(USER_PTR_ERR)int test_strnstr_null2(void *ctx) { return bpf_strnstr("hello", NULL, 1); } + +/* Passing userspace ptr to string kfuncs */ +SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_user_ptr1(void *ctx) { return bpf_strcmp(user_ptr, "hello"); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strcmp_user_ptr2(void *ctx) { return bpf_strcmp("hello", user_ptr); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strchr_user_ptr(void *ctx) { return bpf_strchr(user_ptr, 'a'); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strchrnul_user_ptr(void *ctx) { return bpf_strchrnul(user_ptr, 'a'); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strnchr_user_ptr(void *ctx) { return bpf_strnchr(user_ptr, 1, 'a'); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strrchr_user_ptr(void *ctx) { return bpf_strrchr(user_ptr, 'a'); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strlen_user_ptr(void *ctx) { return bpf_strlen(user_ptr); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strnlen_user_ptr(void *ctx) { return bpf_strnlen(user_ptr, 1); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strspn_user_ptr1(void *ctx) { return bpf_strspn(user_ptr, "hello"); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strspn_user_ptr2(void *ctx) { return bpf_strspn("hello", user_ptr); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strcspn_user_ptr1(void *ctx) { return bpf_strcspn(user_ptr, "hello"); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strcspn_user_ptr2(void *ctx) { return bpf_strcspn("hello", user_ptr); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strstr_user_ptr1(void *ctx) { return bpf_strstr(user_ptr, "hello"); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strstr_user_ptr2(void *ctx) { return bpf_strstr("hello", user_ptr); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strnstr_user_ptr1(void *ctx) { return bpf_strnstr(user_ptr, "hello", 1); } +SEC("syscall") __retval(USER_PTR_ERR) int test_strnstr_user_ptr2(void *ctx) { return bpf_strnstr("hello", user_ptr, 1); } + +#endif /* __TARGET_ARCH_s390 */ + +/* Passing invalid kernel ptr to string kfuncs should always return -EFAULT */ +SEC("syscall") __retval(-EFAULT) int test_strcmp_pagefault1(void *ctx) { return bpf_strcmp(invalid_kern_ptr, "hello"); } +SEC("syscall") __retval(-EFAULT) int test_strcmp_pagefault2(void *ctx) { return bpf_strcmp("hello", invalid_kern_ptr); } +SEC("syscall") __retval(-EFAULT) int test_strchr_pagefault(void *ctx) { return bpf_strchr(invalid_kern_ptr, 'a'); } +SEC("syscall") __retval(-EFAULT) int test_strchrnul_pagefault(void *ctx) { return bpf_strchrnul(invalid_kern_ptr, 'a'); } +SEC("syscall") __retval(-EFAULT) int test_strnchr_pagefault(void *ctx) { return bpf_strnchr(invalid_kern_ptr, 1, 'a'); } +SEC("syscall") __retval(-EFAULT) int test_strrchr_pagefault(void *ctx) { return bpf_strrchr(invalid_kern_ptr, 'a'); } +SEC("syscall") __retval(-EFAULT) int test_strlen_pagefault(void *ctx) { return bpf_strlen(invalid_kern_ptr); } +SEC("syscall") __retval(-EFAULT) int test_strnlen_pagefault(void *ctx) { return bpf_strnlen(invalid_kern_ptr, 1); } +SEC("syscall") __retval(-EFAULT) int test_strspn_pagefault1(void *ctx) { return bpf_strspn(invalid_kern_ptr, "hello"); } +SEC("syscall") __retval(-EFAULT) int test_strspn_pagefault2(void *ctx) { return bpf_strspn("hello", invalid_kern_ptr); } +SEC("syscall") __retval(-EFAULT) int test_strcspn_pagefault1(void *ctx) { return bpf_strcspn(invalid_kern_ptr, "hello"); } +SEC("syscall") __retval(-EFAULT) int test_strcspn_pagefault2(void *ctx) { return bpf_strcspn("hello", invalid_kern_ptr); } +SEC("syscall") __retval(-EFAULT) int test_strstr_pagefault1(void *ctx) { return bpf_strstr(invalid_kern_ptr, "hello"); } +SEC("syscall") __retval(-EFAULT) int test_strstr_pagefault2(void *ctx) { return bpf_strstr("hello", invalid_kern_ptr); } +SEC("syscall") __retval(-EFAULT) int test_strnstr_pagefault1(void *ctx) { return bpf_strnstr(invalid_kern_ptr, "hello", 1); } +SEC("syscall") __retval(-EFAULT) int test_strnstr_pagefault2(void *ctx) { return bpf_strnstr("hello", invalid_kern_ptr, 1); } + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/string_kfuncs_failure2.c b/tools/testing/selftests/bpf/progs/string_kfuncs_failure2.c new file mode 100644 index 000000000000..89fb4669b0e9 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/string_kfuncs_failure2.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2025 Red Hat, Inc.*/ +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include <linux/limits.h> + +char long_str[XATTR_SIZE_MAX + 1]; + +SEC("syscall") int test_strcmp_too_long(void *ctx) { return bpf_strcmp(long_str, long_str); } +SEC("syscall") int test_strchr_too_long(void *ctx) { return bpf_strchr(long_str, 'b'); } +SEC("syscall") int test_strchrnul_too_long(void *ctx) { return bpf_strchrnul(long_str, 'b'); } +SEC("syscall") int test_strnchr_too_long(void *ctx) { return bpf_strnchr(long_str, sizeof(long_str), 'b'); } +SEC("syscall") int test_strrchr_too_long(void *ctx) { return bpf_strrchr(long_str, 'b'); } +SEC("syscall") int test_strlen_too_long(void *ctx) { return bpf_strlen(long_str); } +SEC("syscall") int test_strnlen_too_long(void *ctx) { return bpf_strnlen(long_str, sizeof(long_str)); } +SEC("syscall") int test_strspn_str_too_long(void *ctx) { return bpf_strspn(long_str, "a"); } +SEC("syscall") int test_strspn_accept_too_long(void *ctx) { return bpf_strspn("b", long_str); } +SEC("syscall") int test_strcspn_str_too_long(void *ctx) { return bpf_strcspn(long_str, "b"); } +SEC("syscall") int test_strcspn_reject_too_long(void *ctx) { return bpf_strcspn("b", long_str); } +SEC("syscall") int test_strstr_too_long(void *ctx) { return bpf_strstr(long_str, "hello"); } +SEC("syscall") int test_strnstr_too_long(void *ctx) { return bpf_strnstr(long_str, "hello", sizeof(long_str)); } + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/string_kfuncs_success.c b/tools/testing/selftests/bpf/progs/string_kfuncs_success.c new file mode 100644 index 000000000000..46697f381878 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/string_kfuncs_success.c @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2025 Red Hat, Inc.*/ +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" +#include "errno.h" + +char str[] = "hello world"; + +#define __test(retval) SEC("syscall") __success __retval(retval) + +/* Functional tests */ +__test(0) int test_strcmp_eq(void *ctx) { return bpf_strcmp(str, "hello world"); } +__test(1) int test_strcmp_neq(void *ctx) { return bpf_strcmp(str, "hello"); } +__test(1) int test_strchr_found(void *ctx) { return bpf_strchr(str, 'e'); } +__test(11) int test_strchr_null(void *ctx) { return bpf_strchr(str, '\0'); } +__test(-ENOENT) int test_strchr_notfound(void *ctx) { return bpf_strchr(str, 'x'); } +__test(1) int test_strchrnul_found(void *ctx) { return bpf_strchrnul(str, 'e'); } +__test(11) int test_strchrnul_notfound(void *ctx) { return bpf_strchrnul(str, 'x'); } +__test(1) int test_strnchr_found(void *ctx) { return bpf_strnchr(str, 5, 'e'); } +__test(11) int test_strnchr_null(void *ctx) { return bpf_strnchr(str, 12, '\0'); } +__test(-ENOENT) int test_strnchr_notfound(void *ctx) { return bpf_strnchr(str, 5, 'w'); } +__test(9) int test_strrchr_found(void *ctx) { return bpf_strrchr(str, 'l'); } +__test(11) int test_strrchr_null(void *ctx) { return bpf_strrchr(str, '\0'); } +__test(-ENOENT) int test_strrchr_notfound(void *ctx) { return bpf_strrchr(str, 'x'); } +__test(11) int test_strlen(void *ctx) { return bpf_strlen(str); } +__test(11) int test_strnlen(void *ctx) { return bpf_strnlen(str, 12); } +__test(5) int test_strspn(void *ctx) { return bpf_strspn(str, "ehlo"); } +__test(2) int test_strcspn(void *ctx) { return bpf_strcspn(str, "lo"); } +__test(6) int test_strstr_found(void *ctx) { return bpf_strstr(str, "world"); } +__test(-ENOENT) int test_strstr_notfound(void *ctx) { return bpf_strstr(str, "hi"); } +__test(0) int test_strstr_empty(void *ctx) { return bpf_strstr(str, ""); } +__test(0) int test_strnstr_found(void *ctx) { return bpf_strnstr(str, "hello", 6); } +__test(-ENOENT) int test_strnstr_notfound(void *ctx) { return bpf_strnstr(str, "hi", 10); } +__test(0) int test_strnstr_empty(void *ctx) { return bpf_strnstr(str, "", 1); } + +char _license[] SEC("license") = "GPL"; 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