diff options
Diffstat (limited to 'tools')
17 files changed, 1917 insertions, 11 deletions
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 976b194eb775..4abddb668a10 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -7112,4 +7112,12 @@ enum { BPF_F_TIMER_ABS = (1ULL << 0), }; +/* BPF numbers iterator state */ +struct bpf_iter_num { + /* opaque iterator state; having __u64 here allows to preserve correct + * alignment requirements in vmlinux.h, generated from BTF + */ + __u64 __opaque[1]; +} __attribute__((aligned(8))); + #endif /* _UAPI__LINUX_BPF_H__ */ diff --git a/tools/testing/selftests/bpf/DENYLIST.s390x b/tools/testing/selftests/bpf/DENYLIST.s390x index a02a085e7f32..34cb8b2de8ca 100644 --- a/tools/testing/selftests/bpf/DENYLIST.s390x +++ b/tools/testing/selftests/bpf/DENYLIST.s390x @@ -8,6 +8,7 @@ dynptr/test_dynptr_skb_data dynptr/test_skb_readonly fexit_sleep # fexit_skel_load fexit skeleton failed (trampoline) get_stack_raw_tp # user_stack corrupted user stack (no backchain userspace) +iters/testmod_seq* # s390x doesn't support kfuncs in modules yet kprobe_multi_bench_attach # bpf_program__attach_kprobe_multi_opts unexpected error: -95 kprobe_multi_test # relies on fentry ksyms_module # test_ksyms_module__open_and_load unexpected error: -9 (?) diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c index 46500636d8cd..5e6e85c8d77d 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c @@ -65,6 +65,34 @@ bpf_testmod_test_mod_kfunc(int i) *(int *)this_cpu_ptr(&bpf_testmod_ksym_percpu) = i; } +__bpf_kfunc int bpf_iter_testmod_seq_new(struct bpf_iter_testmod_seq *it, s64 value, int cnt) +{ + if (cnt < 0) { + it->cnt = 0; + return -EINVAL; + } + + it->value = value; + it->cnt = cnt; + + return 0; +} + +__bpf_kfunc s64 *bpf_iter_testmod_seq_next(struct bpf_iter_testmod_seq* it) +{ + if (it->cnt <= 0) + return NULL; + + it->cnt--; + + return &it->value; +} + +__bpf_kfunc void bpf_iter_testmod_seq_destroy(struct bpf_iter_testmod_seq *it) +{ + it->cnt = 0; +} + struct bpf_testmod_btf_type_tag_1 { int a; }; @@ -220,6 +248,17 @@ static struct bin_attribute bin_attr_bpf_testmod_file __ro_after_init = { .write = bpf_testmod_test_write, }; +BTF_SET8_START(bpf_testmod_common_kfunc_ids) +BTF_ID_FLAGS(func, bpf_iter_testmod_seq_new, KF_ITER_NEW) +BTF_ID_FLAGS(func, bpf_iter_testmod_seq_next, KF_ITER_NEXT | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_iter_testmod_seq_destroy, KF_ITER_DESTROY) +BTF_SET8_END(bpf_testmod_common_kfunc_ids) + +static const struct btf_kfunc_id_set bpf_testmod_common_kfunc_set = { + .owner = THIS_MODULE, + .set = &bpf_testmod_common_kfunc_ids, +}; + BTF_SET8_START(bpf_testmod_check_kfunc_ids) BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc) BTF_SET8_END(bpf_testmod_check_kfunc_ids) @@ -235,7 +274,8 @@ static int bpf_testmod_init(void) { int ret; - ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_testmod_kfunc_set); + ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_UNSPEC, &bpf_testmod_common_kfunc_set); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_testmod_kfunc_set); if (ret < 0) return ret; if (bpf_fentry_test1(0) < 0) diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h index 0d71e2607832..f32793efe095 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h @@ -22,4 +22,10 @@ struct bpf_testmod_test_writable_ctx { int val; }; +/* BPF iter that returns *value* *n* times in a row */ +struct bpf_iter_testmod_seq { + s64 value; + int cnt; +}; + #endif /* _BPF_TESTMOD_H */ diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c b/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c index 5ca252823294..731c343897d8 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_verif_scale.c @@ -144,6 +144,12 @@ void test_verif_scale_pyperf600_nounroll() scale_test("pyperf600_nounroll.bpf.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false); } +void test_verif_scale_pyperf600_iter() +{ + /* open-coded BPF iterator version */ + scale_test("pyperf600_iter.bpf.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false); +} + void test_verif_scale_loop1() { scale_test("loop1.bpf.o", BPF_PROG_TYPE_RAW_TRACEPOINT, false); diff --git a/tools/testing/selftests/bpf/prog_tests/iters.c b/tools/testing/selftests/bpf/prog_tests/iters.c new file mode 100644 index 000000000000..10804ae5ae97 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/iters.c @@ -0,0 +1,106 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include <test_progs.h> + +#include "iters.skel.h" +#include "iters_state_safety.skel.h" +#include "iters_looping.skel.h" +#include "iters_num.skel.h" +#include "iters_testmod_seq.skel.h" + +static void subtest_num_iters(void) +{ + struct iters_num *skel; + int err; + + skel = iters_num__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_open_and_load")) + return; + + err = iters_num__attach(skel); + if (!ASSERT_OK(err, "skel_attach")) + goto cleanup; + + usleep(1); + iters_num__detach(skel); + +#define VALIDATE_CASE(case_name) \ + ASSERT_EQ(skel->bss->res_##case_name, \ + skel->rodata->exp_##case_name, \ + #case_name) + + VALIDATE_CASE(empty_zero); + VALIDATE_CASE(empty_int_min); + VALIDATE_CASE(empty_int_max); + VALIDATE_CASE(empty_minus_one); + + VALIDATE_CASE(simple_sum); + VALIDATE_CASE(neg_sum); + VALIDATE_CASE(very_neg_sum); + VALIDATE_CASE(neg_pos_sum); + + VALIDATE_CASE(invalid_range); + VALIDATE_CASE(max_range); + VALIDATE_CASE(e2big_range); + + VALIDATE_CASE(succ_elem_cnt); + VALIDATE_CASE(overfetched_elem_cnt); + VALIDATE_CASE(fail_elem_cnt); + +#undef VALIDATE_CASE + +cleanup: + iters_num__destroy(skel); +} + +static void subtest_testmod_seq_iters(void) +{ + struct iters_testmod_seq *skel; + int err; + + if (!env.has_testmod) { + test__skip(); + return; + } + + skel = iters_testmod_seq__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_open_and_load")) + return; + + err = iters_testmod_seq__attach(skel); + if (!ASSERT_OK(err, "skel_attach")) + goto cleanup; + + usleep(1); + iters_testmod_seq__detach(skel); + +#define VALIDATE_CASE(case_name) \ + ASSERT_EQ(skel->bss->res_##case_name, \ + skel->rodata->exp_##case_name, \ + #case_name) + + VALIDATE_CASE(empty); + VALIDATE_CASE(full); + VALIDATE_CASE(truncated); + +#undef VALIDATE_CASE + +cleanup: + iters_testmod_seq__destroy(skel); +} + +void test_iters(void) +{ + RUN_TESTS(iters_state_safety); + RUN_TESTS(iters_looping); + RUN_TESTS(iters); + + if (env.has_testmod) + RUN_TESTS(iters_testmod_seq); + + if (test__start_subtest("num")) + subtest_num_iters(); + if (test__start_subtest("testmod_seq")) + subtest_testmod_seq_iters(); +} diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_autoattach.c b/tools/testing/selftests/bpf/prog_tests/uprobe_autoattach.c index 6558c857e620..d5b3377aa33c 100644 --- a/tools/testing/selftests/bpf/prog_tests/uprobe_autoattach.c +++ b/tools/testing/selftests/bpf/prog_tests/uprobe_autoattach.c @@ -3,7 +3,6 @@ #include <test_progs.h> #include "test_uprobe_autoattach.skel.h" -#include "progs/bpf_misc.h" /* uprobe attach point */ static noinline int autoattach_trigger_func(int arg1, int arg2, int arg3, diff --git a/tools/testing/selftests/bpf/progs/bpf_misc.h b/tools/testing/selftests/bpf/progs/bpf_misc.h index f704885aa534..43b154a639e7 100644 --- a/tools/testing/selftests/bpf/progs/bpf_misc.h +++ b/tools/testing/selftests/bpf/progs/bpf_misc.h @@ -36,6 +36,7 @@ #define __clobber_common "r0", "r1", "r2", "r3", "r4", "r5", "memory" #define __imm(name) [name]"i"(name) #define __imm_addr(name) [name]"i"(&name) +#define __imm_ptr(name) [name]"p"(&name) #if defined(__TARGET_ARCH_x86) #define SYSCALL_WRAPPER 1 @@ -75,5 +76,104 @@ #define FUNC_REG_ARG_CNT 5 #endif +struct bpf_iter_num; + +extern int bpf_iter_num_new(struct bpf_iter_num *it, int start, int end) __ksym; +extern int *bpf_iter_num_next(struct bpf_iter_num *it) __ksym; +extern void bpf_iter_num_destroy(struct bpf_iter_num *it) __ksym; + +#ifndef bpf_for_each +/* bpf_for_each(iter_type, cur_elem, args...) provides generic construct for + * using BPF open-coded iterators without having to write mundane explicit + * low-level loop logic. Instead, it provides for()-like generic construct + * that can be used pretty naturally. E.g., for some hypothetical cgroup + * iterator, you'd write: + * + * struct cgroup *cg, *parent_cg = <...>; + * + * bpf_for_each(cgroup, cg, parent_cg, CG_ITER_CHILDREN) { + * bpf_printk("Child cgroup id = %d", cg->cgroup_id); + * if (cg->cgroup_id == 123) + * break; + * } + * + * I.e., it looks almost like high-level for each loop in other languages, + * supports continue/break, and is verifiable by BPF verifier. + * + * For iterating integers, the difference betwen bpf_for_each(num, i, N, M) + * and bpf_for(i, N, M) is in that bpf_for() provides additional proof to + * verifier that i is in [N, M) range, and in bpf_for_each() case i is `int + * *`, not just `int`. So for integers bpf_for() is more convenient. + * + * Note: this macro relies on C99 feature of allowing to declare variables + * inside for() loop, bound to for() loop lifetime. It also utilizes GCC + * extension: __attribute__((cleanup(<func>))), supported by both GCC and + * Clang. + */ +#define bpf_for_each(type, cur, args...) for ( \ + /* initialize and define destructor */ \ + struct bpf_iter_##type ___it __attribute__((aligned(8), /* enforce, just in case */, \ + cleanup(bpf_iter_##type##_destroy))), \ + /* ___p pointer is just to call bpf_iter_##type##_new() *once* to init ___it */ \ + *___p = (bpf_iter_##type##_new(&___it, ##args), \ + /* this is a workaround for Clang bug: it currently doesn't emit BTF */ \ + /* for bpf_iter_##type##_destroy() when used from cleanup() attribute */ \ + (void)bpf_iter_##type##_destroy, (void *)0); \ + /* iteration and termination check */ \ + (((cur) = bpf_iter_##type##_next(&___it))); \ +) +#endif /* bpf_for_each */ + +#ifndef bpf_for +/* bpf_for(i, start, end) implements a for()-like looping construct that sets + * provided integer variable *i* to values starting from *start* through, + * but not including, *end*. It also proves to BPF verifier that *i* belongs + * to range [start, end), so this can be used for accessing arrays without + * extra checks. + * + * Note: *start* and *end* are assumed to be expressions with no side effects + * and whose values do not change throughout bpf_for() loop execution. They do + * not have to be statically known or constant, though. + * + * Note: similarly to bpf_for_each(), it relies on C99 feature of declaring for() + * loop bound variables and cleanup attribute, supported by GCC and Clang. + */ +#define bpf_for(i, start, end) for ( \ + /* initialize and define destructor */ \ + struct bpf_iter_num ___it __attribute__((aligned(8), /* enforce, just in case */ \ + cleanup(bpf_iter_num_destroy))), \ + /* ___p pointer is necessary to call bpf_iter_num_new() *once* to init ___it */ \ + *___p = (bpf_iter_num_new(&___it, (start), (end)), \ + /* this is a workaround for Clang bug: it currently doesn't emit BTF */ \ + /* for bpf_iter_num_destroy() when used from cleanup() attribute */ \ + (void)bpf_iter_num_destroy, (void *)0); \ + ({ \ + /* iteration step */ \ + int *___t = bpf_iter_num_next(&___it); \ + /* termination and bounds check */ \ + (___t && ((i) = *___t, (i) >= (start) && (i) < (end))); \ + }); \ +) +#endif /* bpf_for */ + +#ifndef bpf_repeat +/* bpf_repeat(N) performs N iterations without exposing iteration number + * + * Note: similarly to bpf_for_each(), it relies on C99 feature of declaring for() + * loop bound variables and cleanup attribute, supported by GCC and Clang. + */ +#define bpf_repeat(N) for ( \ + /* initialize and define destructor */ \ + struct bpf_iter_num ___it __attribute__((aligned(8), /* enforce, just in case */ \ + cleanup(bpf_iter_num_destroy))), \ + /* ___p pointer is necessary to call bpf_iter_num_new() *once* to init ___it */ \ + *___p = (bpf_iter_num_new(&___it, 0, (N)), \ + /* this is a workaround for Clang bug: it currently doesn't emit BTF */ \ + /* for bpf_iter_num_destroy() when used from cleanup() attribute */ \ + (void)bpf_iter_num_destroy, (void *)0); \ + bpf_iter_num_next(&___it); \ + /* nothing here */ \ +) +#endif /* bpf_repeat */ #endif diff --git a/tools/testing/selftests/bpf/progs/iters.c b/tools/testing/selftests/bpf/progs/iters.c new file mode 100644 index 000000000000..84e5dc10243c --- /dev/null +++ b/tools/testing/selftests/bpf/progs/iters.c @@ -0,0 +1,720 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include <stdbool.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) + +static volatile int zero = 0; + +int my_pid; +int arr[256]; +int small_arr[16] SEC(".data.small_arr"); + +#ifdef REAL_TEST +#define MY_PID_GUARD() if (my_pid != (bpf_get_current_pid_tgid() >> 32)) return 0 +#else +#define MY_PID_GUARD() ({ }) +#endif + +SEC("?raw_tp") +__failure __msg("math between map_value pointer and register with unbounded min value is not allowed") +int iter_err_unsafe_c_loop(const void *ctx) +{ + struct bpf_iter_num it; + int *v, i = zero; /* obscure initial value of i */ + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 0, 1000); + while ((v = bpf_iter_num_next(&it))) { + i++; + } + bpf_iter_num_destroy(&it); + + small_arr[i] = 123; /* invalid */ + + return 0; +} + +SEC("?raw_tp") +__failure __msg("unbounded memory access") +int iter_err_unsafe_asm_loop(const void *ctx) +{ + struct bpf_iter_num it; + int *v, i = 0; + + MY_PID_GUARD(); + + asm volatile ( + "r6 = %[zero];" /* iteration counter */ + "r1 = %[it];" /* iterator state */ + "r2 = 0;" + "r3 = 1000;" + "r4 = 1;" + "call %[bpf_iter_num_new];" + "loop:" + "r1 = %[it];" + "call %[bpf_iter_num_next];" + "if r0 == 0 goto out;" + "r6 += 1;" + "goto loop;" + "out:" + "r1 = %[it];" + "call %[bpf_iter_num_destroy];" + "r1 = %[small_arr];" + "r2 = r6;" + "r2 <<= 2;" + "r1 += r2;" + "*(u32 *)(r1 + 0) = r6;" /* invalid */ + : + : [it]"r"(&it), + [small_arr]"p"(small_arr), + [zero]"p"(zero), + __imm(bpf_iter_num_new), + __imm(bpf_iter_num_next), + __imm(bpf_iter_num_destroy) + : __clobber_common, "r6" + ); + + return 0; +} + +SEC("raw_tp") +__success +int iter_while_loop(const void *ctx) +{ + struct bpf_iter_num it; + int *v, i; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 0, 3); + while ((v = bpf_iter_num_next(&it))) { + bpf_printk("ITER_BASIC: E1 VAL: v=%d", *v); + } + bpf_iter_num_destroy(&it); + + return 0; +} + +SEC("raw_tp") +__success +int iter_while_loop_auto_cleanup(const void *ctx) +{ + __attribute__((cleanup(bpf_iter_num_destroy))) struct bpf_iter_num it; + int *v, i; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 0, 3); + while ((v = bpf_iter_num_next(&it))) { + bpf_printk("ITER_BASIC: E1 VAL: v=%d", *v); + } + /* (!) no explicit bpf_iter_num_destroy() */ + + return 0; +} + +SEC("raw_tp") +__success +int iter_for_loop(const void *ctx) +{ + struct bpf_iter_num it; + int *v, i; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 5, 10); + for (v = bpf_iter_num_next(&it); v; v = bpf_iter_num_next(&it)) { + bpf_printk("ITER_BASIC: E2 VAL: v=%d", *v); + } + bpf_iter_num_destroy(&it); + + return 0; +} + +SEC("raw_tp") +__success +int iter_bpf_for_each_macro(const void *ctx) +{ + int *v; + + MY_PID_GUARD(); + + bpf_for_each(num, v, 5, 10) { + bpf_printk("ITER_BASIC: E2 VAL: v=%d", *v); + } + + return 0; +} + +SEC("raw_tp") +__success +int iter_bpf_for_macro(const void *ctx) +{ + int i; + + MY_PID_GUARD(); + + bpf_for(i, 5, 10) { + bpf_printk("ITER_BASIC: E2 VAL: v=%d", i); + } + + return 0; +} + +SEC("raw_tp") +__success +int iter_pragma_unroll_loop(const void *ctx) +{ + struct bpf_iter_num it; + int *v, i; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 0, 2); +#pragma nounroll + for (i = 0; i < 3; i++) { + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E3 VAL: i=%d v=%d", i, v ? *v : -1); + } + bpf_iter_num_destroy(&it); + + return 0; +} + +SEC("raw_tp") +__success +int iter_manual_unroll_loop(const void *ctx) +{ + struct bpf_iter_num it; + int *v, i; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 100, 200); + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E4 VAL: v=%d", v ? *v : -1); + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E4 VAL: v=%d", v ? *v : -1); + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E4 VAL: v=%d", v ? *v : -1); + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E4 VAL: v=%d\n", v ? *v : -1); + bpf_iter_num_destroy(&it); + + return 0; +} + +SEC("raw_tp") +__success +int iter_multiple_sequential_loops(const void *ctx) +{ + struct bpf_iter_num it; + int *v, i; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 0, 3); + while ((v = bpf_iter_num_next(&it))) { + bpf_printk("ITER_BASIC: E1 VAL: v=%d", *v); + } + bpf_iter_num_destroy(&it); + + bpf_iter_num_new(&it, 5, 10); + for (v = bpf_iter_num_next(&it); v; v = bpf_iter_num_next(&it)) { + bpf_printk("ITER_BASIC: E2 VAL: v=%d", *v); + } + bpf_iter_num_destroy(&it); + + bpf_iter_num_new(&it, 0, 2); +#pragma nounroll + for (i = 0; i < 3; i++) { + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E3 VAL: i=%d v=%d", i, v ? *v : -1); + } + bpf_iter_num_destroy(&it); + + bpf_iter_num_new(&it, 100, 200); + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E4 VAL: v=%d", v ? *v : -1); + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E4 VAL: v=%d", v ? *v : -1); + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E4 VAL: v=%d", v ? *v : -1); + v = bpf_iter_num_next(&it); + bpf_printk("ITER_BASIC: E4 VAL: v=%d\n", v ? *v : -1); + bpf_iter_num_destroy(&it); + + return 0; +} + +SEC("raw_tp") +__success +int iter_limit_cond_break_loop(const void *ctx) +{ + struct bpf_iter_num it; + int *v, i = 0, sum = 0; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 0, 10); + while ((v = bpf_iter_num_next(&it))) { + bpf_printk("ITER_SIMPLE: i=%d v=%d", i, *v); + sum += *v; + + i++; + if (i > 3) + break; + } + bpf_iter_num_destroy(&it); + + bpf_printk("ITER_SIMPLE: sum=%d\n", sum); + + return 0; +} + +SEC("raw_tp") +__success +int iter_obfuscate_counter(const void *ctx) +{ + struct bpf_iter_num it; + int *v, sum = 0; + /* Make i's initial value unknowable for verifier to prevent it from + * pruning if/else branch inside the loop body and marking i as precise. + */ + int i = zero; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 0, 10); + while ((v = bpf_iter_num_next(&it))) { + int x; + + i += 1; + + /* If we initialized i as `int i = 0;` above, verifier would + * track that i becomes 1 on first iteration after increment + * above, and here verifier would eagerly prune else branch + * and mark i as precise, ruining open-coded iterator logic + * completely, as each next iteration would have a different + * *precise* value of i, and thus there would be no + * convergence of state. This would result in reaching maximum + * instruction limit, no matter what the limit is. + */ + if (i == 1) + x = 123; + else + x = i * 3 + 1; + + bpf_printk("ITER_OBFUSCATE_COUNTER: i=%d v=%d x=%d", i, *v, x); + + sum += x; + } + bpf_iter_num_destroy(&it); + + bpf_printk("ITER_OBFUSCATE_COUNTER: sum=%d\n", sum); + + return 0; +} + +SEC("raw_tp") +__success +int iter_search_loop(const void *ctx) +{ + struct bpf_iter_num it; + int *v, *elem = NULL; + bool found = false; + + MY_PID_GUARD(); + + bpf_iter_num_new(&it, 0, 10); + + while ((v = bpf_iter_num_next(&it))) { + bpf_printk("ITER_SEARCH_LOOP: v=%d", *v); + + if (*v == 2) { + found = true; + elem = v; + barrier_var(elem); + } + } + + /* should fail to verify if bpf_iter_num_destroy() is here */ + + if (found) + /* here found element will be wrong, we should have copied + * value to a variable, but here we want to make sure we can + * access memory after the loop anyways + */ + bpf_printk("ITER_SEARCH_LOOP: FOUND IT = %d!\n", *elem); + else + bpf_printk("ITER_SEARCH_LOOP: NOT FOUND IT!\n"); + + bpf_iter_num_destroy(&it); + + return 0; +} + +SEC("raw_tp") +__success +int iter_array_fill(const void *ctx) +{ + int sum, i; + + MY_PID_GUARD(); + + bpf_for(i, 0, ARRAY_SIZE(arr)) { + arr[i] = i * 2; + } + + sum = 0; + bpf_for(i, 0, ARRAY_SIZE(arr)) { + sum += arr[i]; + } + + bpf_printk("ITER_ARRAY_FILL: sum=%d (should be %d)\n", sum, 255 * 256); + + return 0; +} + +static int arr2d[4][5]; +static int arr2d_row_sums[4]; +static int arr2d_col_sums[5]; + +SEC("raw_tp") +__success +int iter_nested_iters(const void *ctx) +{ + int sum, row, col; + + MY_PID_GUARD(); + + bpf_for(row, 0, ARRAY_SIZE(arr2d)) { + bpf_for( col, 0, ARRAY_SIZE(arr2d[0])) { + arr2d[row][col] = row * col; + } + } + + /* zero-initialize sums */ + sum = 0; + bpf_for(row, 0, ARRAY_SIZE(arr2d)) { + arr2d_row_sums[row] = 0; + } + bpf_for(col, 0, ARRAY_SIZE(arr2d[0])) { + arr2d_col_sums[col] = 0; + } + + /* calculate sums */ + bpf_for(row, 0, ARRAY_SIZE(arr2d)) { + bpf_for(col, 0, ARRAY_SIZE(arr2d[0])) { + sum += arr2d[row][col]; + arr2d_row_sums[row] += arr2d[row][col]; + arr2d_col_sums[col] += arr2d[row][col]; + } + } + + bpf_printk("ITER_NESTED_ITERS: total sum=%d", sum); + bpf_for(row, 0, ARRAY_SIZE(arr2d)) { + bpf_printk("ITER_NESTED_ITERS: row #%d sum=%d", row, arr2d_row_sums[row]); + } + bpf_for(col, 0, ARRAY_SIZE(arr2d[0])) { + bpf_printk("ITER_NESTED_ITERS: col #%d sum=%d%s", + col, arr2d_col_sums[col], + col == ARRAY_SIZE(arr2d[0]) - 1 ? "\n" : ""); + } + + return 0; +} + +SEC("raw_tp") +__success +int iter_nested_deeply_iters(const void *ctx) +{ + int sum = 0; + + MY_PID_GUARD(); + + bpf_repeat(10) { + bpf_repeat(10) { + bpf_repeat(10) { + bpf_repeat(10) { + bpf_repeat(10) { + sum += 1; + } + } + } + } + /* validate that we can break from inside bpf_repeat() */ + break; + } + + return sum; +} + +static __noinline void fill_inner_dimension(int row) +{ + int col; + + bpf_for(col, 0, ARRAY_SIZE(arr2d[0])) { + arr2d[row][col] = row * col; + } +} + +static __noinline int sum_inner_dimension(int row) +{ + int sum = 0, col; + + bpf_for(col, 0, ARRAY_SIZE(arr2d[0])) { + sum += arr2d[row][col]; + arr2d_row_sums[row] += arr2d[row][col]; + arr2d_col_sums[col] += arr2d[row][col]; + } + + return sum; +} + +SEC("raw_tp") +__success +int iter_subprog_iters(const void *ctx) +{ + int sum, row, col; + + MY_PID_GUARD(); + + bpf_for(row, 0, ARRAY_SIZE(arr2d)) { + fill_inner_dimension(row); + } + + /* zero-initialize sums */ + sum = 0; + bpf_for(row, 0, ARRAY_SIZE(arr2d)) { + arr2d_row_sums[row] = 0; + } + bpf_for(col, 0, ARRAY_SIZE(arr2d[0])) { + arr2d_col_sums[col] = 0; + } + + /* calculate sums */ + bpf_for(row, 0, ARRAY_SIZE(arr2d)) { + sum += sum_inner_dimension(row); + } + + bpf_printk("ITER_SUBPROG_ITERS: total sum=%d", sum); + bpf_for(row, 0, ARRAY_SIZE(arr2d)) { + bpf_printk("ITER_SUBPROG_ITERS: row #%d sum=%d", + row, arr2d_row_sums[row]); + } + bpf_for(col, 0, ARRAY_SIZE(arr2d[0])) { + bpf_printk("ITER_SUBPROG_ITERS: col #%d sum=%d%s", + col, arr2d_col_sums[col], + col == ARRAY_SIZE(arr2d[0]) - 1 ? "\n" : ""); + } + + return 0; +} + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, int); + __type(value, int); + __uint(max_entries, 1000); +} arr_map SEC(".maps"); + +SEC("?raw_tp") +__failure __msg("invalid mem access 'scalar'") +int iter_err_too_permissive1(const void *ctx) +{ + int *map_val = NULL; + int key = 0; + + MY_PID_GUARD(); + + map_val = bpf_map_lookup_elem(&arr_map, &key); + if (!map_val) + return 0; + + bpf_repeat(1000000) { + map_val = NULL; + } + + *map_val = 123; + + return 0; +} + +SEC("?raw_tp") +__failure __msg("invalid mem access 'map_value_or_null'") +int iter_err_too_permissive2(const void *ctx) +{ + int *map_val = NULL; + int key = 0; + + MY_PID_GUARD(); + + map_val = bpf_map_lookup_elem(&arr_map, &key); + if (!map_val) + return 0; + + bpf_repeat(1000000) { + map_val = bpf_map_lookup_elem(&arr_map, &key); + } + + *map_val = 123; + + return 0; +} + +SEC("?raw_tp") +__failure __msg("invalid mem access 'map_value_or_null'") +int iter_err_too_permissive3(const void *ctx) +{ + int *map_val = NULL; + int key = 0; + bool found = false; + + MY_PID_GUARD(); + + bpf_repeat(1000000) { + map_val = bpf_map_lookup_elem(&arr_map, &key); + found = true; + } + + if (found) + *map_val = 123; + + return 0; +} + +SEC("raw_tp") +__success +int iter_tricky_but_fine(const void *ctx) +{ + int *map_val = NULL; + int key = 0; + bool found = false; + + MY_PID_GUARD(); + + bpf_repeat(1000000) { + map_val = bpf_map_lookup_elem(&arr_map, &key); + if (map_val) { + found = true; + break; + } + } + + if (found) + *map_val = 123; + + return 0; +} + +#define __bpf_memzero(p, sz) bpf_probe_read_kernel((p), (sz), 0) + +SEC("raw_tp") +__success +int iter_stack_array_loop(const void *ctx) +{ + long arr1[16], arr2[16], sum = 0; + int *v, i; + + MY_PID_GUARD(); + + /* zero-init arr1 and arr2 in such a way that verifier doesn't know + * it's all zeros; if we don't do that, we'll make BPF verifier track + * all combination of zero/non-zero stack slots for arr1/arr2, which + * will lead to O(2^(ARRAY_SIZE(arr1)+ARRAY_SIZE(arr2))) different + * states + */ + __bpf_memzero(arr1, sizeof(arr1)); + __bpf_memzero(arr2, sizeof(arr1)); + + /* validate that we can break and continue when using bpf_for() */ + bpf_for(i, 0, ARRAY_SIZE(arr1)) { + if (i & 1) { + arr1[i] = i; + continue; + } else { + arr2[i] = i; + break; + } + } + + bpf_for(i, 0, ARRAY_SIZE(arr1)) { + sum += arr1[i] + arr2[i]; + } + + return sum; +} + +static __noinline void fill(struct bpf_iter_num *it, int *arr, __u32 n, int mul) +{ + int *t, i; + + while ((t = bpf_iter_num_next(it))) { + i = *t; + if (i >= n) + break; + arr[i] = i * mul; + } +} + +static __noinline int sum(struct bpf_iter_num *it, int *arr, __u32 n) +{ + int *t, i, sum = 0;; + + while ((t = bpf_iter_num_next(it))) { + i = *t; + if (i >= n) + break; + sum += arr[i]; + } + + return sum; +} + +SEC("raw_tp") +__success +int iter_pass_iter_ptr_to_subprog(const void *ctx) +{ + int arr1[16], arr2[32]; + struct bpf_iter_num it; + int n, sum1, sum2; + + MY_PID_GUARD(); + + /* fill arr1 */ + n = ARRAY_SIZE(arr1); + bpf_iter_num_new(&it, 0, n); + fill(&it, arr1, n, 2); + bpf_iter_num_destroy(&it); + + /* fill arr2 */ + n = ARRAY_SIZE(arr2); + bpf_iter_num_new(&it, 0, n); + fill(&it, arr2, n, 10); + bpf_iter_num_destroy(&it); + + /* sum arr1 */ + n = ARRAY_SIZE(arr1); + bpf_iter_num_new(&it, 0, n); + sum1 = sum(&it, arr1, n); + bpf_iter_num_destroy(&it); + + /* sum arr2 */ + n = ARRAY_SIZE(arr2); + bpf_iter_num_new(&it, 0, n); + sum2 = sum(&it, arr2, n); + bpf_iter_num_destroy(&it); + + bpf_printk("sum1=%d, sum2=%d", sum1, sum2); + + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/iters_looping.c b/tools/testing/selftests/bpf/progs/iters_looping.c new file mode 100644 index 000000000000..05fa5ce7fc59 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/iters_looping.c @@ -0,0 +1,163 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include <errno.h> +#include <string.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +char _license[] SEC("license") = "GPL"; + +#define ITER_HELPERS \ + __imm(bpf_iter_num_new), \ + __imm(bpf_iter_num_next), \ + __imm(bpf_iter_num_destroy) + +SEC("?raw_tp") +__success +int force_clang_to_emit_btf_for_externs(void *ctx) +{ + /* we need this as a workaround to enforce compiler emitting BTF + * information for bpf_iter_num_{new,next,destroy}() kfuncs, + * as, apparently, it doesn't emit it for symbols only referenced from + * assembly (or cleanup attribute, for that matter, as well) + */ + bpf_repeat(0); + + return 0; +} + +SEC("?raw_tp") +__success +int consume_first_item_only(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + + /* consume first item */ + "r1 = %[iter];" + "call %[bpf_iter_num_next];" + + "if r0 == 0 goto +1;" + "r0 = *(u32 *)(r0 + 0);" + + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("R0 invalid mem access 'scalar'") +int missing_null_check_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + + /* consume first element */ + "r1 = %[iter];" + "call %[bpf_iter_num_next];" + + /* FAIL: deref with no NULL check */ + "r1 = *(u32 *)(r0 + 0);" + + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure +__msg("invalid access to memory, mem_size=4 off=0 size=8") +__msg("R0 min value is outside of the allowed memory range") +int wrong_sized_read_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + + /* consume first element */ + "r1 = %[iter];" + "call %[bpf_iter_num_next];" + + "if r0 == 0 goto +1;" + /* FAIL: deref more than available 4 bytes */ + "r0 = *(u64 *)(r0 + 0);" + + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__success __log_level(2) +__flag(BPF_F_TEST_STATE_FREQ) +int simplest_loop(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + "r6 = 0;" /* init sum */ + + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 10;" + "call %[bpf_iter_num_new];" + + "1:" + /* consume next item */ + "r1 = %[iter];" + "call %[bpf_iter_num_next];" + + "if r0 == 0 goto 2f;" + "r0 = *(u32 *)(r0 + 0);" + "r6 += r0;" /* accumulate sum */ + "goto 1b;" + + "2:" + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common, "r6" + ); + + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/iters_num.c b/tools/testing/selftests/bpf/progs/iters_num.c new file mode 100644 index 000000000000..7a77a8daee0d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/iters_num.c @@ -0,0 +1,242 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include <limits.h> +#include <linux/errno.h> +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +const volatile __s64 exp_empty_zero = 0 + 1; +__s64 res_empty_zero; + +SEC("raw_tp/sys_enter") +int num_empty_zero(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, 0, 0) sum += i; + res_empty_zero = 1 + sum; + + return 0; +} + +const volatile __s64 exp_empty_int_min = 0 + 2; +__s64 res_empty_int_min; + +SEC("raw_tp/sys_enter") +int num_empty_int_min(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, INT_MIN, INT_MIN) sum += i; + res_empty_int_min = 2 + sum; + + return 0; +} + +const volatile __s64 exp_empty_int_max = 0 + 3; +__s64 res_empty_int_max; + +SEC("raw_tp/sys_enter") +int num_empty_int_max(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, INT_MAX, INT_MAX) sum += i; + res_empty_int_max = 3 + sum; + + return 0; +} + +const volatile __s64 exp_empty_minus_one = 0 + 4; +__s64 res_empty_minus_one; + +SEC("raw_tp/sys_enter") +int num_empty_minus_one(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, -1, -1) sum += i; + res_empty_minus_one = 4 + sum; + + return 0; +} + +const volatile __s64 exp_simple_sum = 9 * 10 / 2; +__s64 res_simple_sum; + +SEC("raw_tp/sys_enter") +int num_simple_sum(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, 0, 10) sum += i; + res_simple_sum = sum; + + return 0; +} + +const volatile __s64 exp_neg_sum = -11 * 10 / 2; +__s64 res_neg_sum; + +SEC("raw_tp/sys_enter") +int num_neg_sum(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, -10, 0) sum += i; + res_neg_sum = sum; + + return 0; +} + +const volatile __s64 exp_very_neg_sum = INT_MIN + (__s64)(INT_MIN + 1); +__s64 res_very_neg_sum; + +SEC("raw_tp/sys_enter") +int num_very_neg_sum(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, INT_MIN, INT_MIN + 2) sum += i; + res_very_neg_sum = sum; + + return 0; +} + +const volatile __s64 exp_very_big_sum = (__s64)(INT_MAX - 1) + (__s64)(INT_MAX - 2); +__s64 res_very_big_sum; + +SEC("raw_tp/sys_enter") +int num_very_big_sum(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, INT_MAX - 2, INT_MAX) sum += i; + res_very_big_sum = sum; + + return 0; +} + +const volatile __s64 exp_neg_pos_sum = -3; +__s64 res_neg_pos_sum; + +SEC("raw_tp/sys_enter") +int num_neg_pos_sum(const void *ctx) +{ + __s64 sum = 0, i; + + bpf_for(i, -3, 3) sum += i; + res_neg_pos_sum = sum; + + return 0; +} + +const volatile __s64 exp_invalid_range = -EINVAL; +__s64 res_invalid_range; + +SEC("raw_tp/sys_enter") +int num_invalid_range(const void *ctx) +{ + struct bpf_iter_num it; + + res_invalid_range = bpf_iter_num_new(&it, 1, 0); + bpf_iter_num_destroy(&it); + + return 0; +} + +const volatile __s64 exp_max_range = 0 + 10; +__s64 res_max_range; + +SEC("raw_tp/sys_enter") +int num_max_range(const void *ctx) +{ + struct bpf_iter_num it; + + res_max_range = 10 + bpf_iter_num_new(&it, 0, BPF_MAX_LOOPS); + bpf_iter_num_destroy(&it); + + return 0; +} + +const volatile __s64 exp_e2big_range = -E2BIG; +__s64 res_e2big_range; + +SEC("raw_tp/sys_enter") +int num_e2big_range(const void *ctx) +{ + struct bpf_iter_num it; + + res_e2big_range = bpf_iter_num_new(&it, -1, BPF_MAX_LOOPS); + bpf_iter_num_destroy(&it); + + return 0; +} + +const volatile __s64 exp_succ_elem_cnt = 10; +__s64 res_succ_elem_cnt; + +SEC("raw_tp/sys_enter") +int num_succ_elem_cnt(const void *ctx) +{ + struct bpf_iter_num it; + int cnt = 0, *v; + + bpf_iter_num_new(&it, 0, 10); + while ((v = bpf_iter_num_next(&it))) { + cnt++; + } + bpf_iter_num_destroy(&it); + + res_succ_elem_cnt = cnt; + + return 0; +} + +const volatile __s64 exp_overfetched_elem_cnt = 5; +__s64 res_overfetched_elem_cnt; + +SEC("raw_tp/sys_enter") +int num_overfetched_elem_cnt(const void *ctx) +{ + struct bpf_iter_num it; + int cnt = 0, *v, i; + + bpf_iter_num_new(&it, 0, 5); + for (i = 0; i < 10; i++) { + v = bpf_iter_num_next(&it); + if (v) + cnt++; + } + bpf_iter_num_destroy(&it); + + res_overfetched_elem_cnt = cnt; + + return 0; +} + +const volatile __s64 exp_fail_elem_cnt = 20 + 0; +__s64 res_fail_elem_cnt; + +SEC("raw_tp/sys_enter") +int num_fail_elem_cnt(const void *ctx) +{ + struct bpf_iter_num it; + int cnt = 0, *v, i; + + bpf_iter_num_new(&it, 100, 10); + for (i = 0; i < 10; i++) { + v = bpf_iter_num_next(&it); + if (v) + cnt++; + } + bpf_iter_num_destroy(&it); + + res_fail_elem_cnt = 20 + cnt; + + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/iters_state_safety.c b/tools/testing/selftests/bpf/progs/iters_state_safety.c new file mode 100644 index 000000000000..d47e59aba6de --- /dev/null +++ b/tools/testing/selftests/bpf/progs/iters_state_safety.c @@ -0,0 +1,426 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2022 Facebook */ + +#include <errno.h> +#include <string.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +char _license[] SEC("license") = "GPL"; + +#define ITER_HELPERS \ + __imm(bpf_iter_num_new), \ + __imm(bpf_iter_num_next), \ + __imm(bpf_iter_num_destroy) + +SEC("?raw_tp") +__success +int force_clang_to_emit_btf_for_externs(void *ctx) +{ + /* we need this as a workaround to enforce compiler emitting BTF + * information for bpf_iter_num_{new,next,destroy}() kfuncs, + * as, apparently, it doesn't emit it for symbols only referenced from + * assembly (or cleanup attribute, for that matter, as well) + */ + bpf_repeat(0); + + return 0; +} + +SEC("?raw_tp") +__success __log_level(2) +__msg("fp-8_w=iter_num(ref_id=1,state=active,depth=0)") +int create_and_destroy(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("Unreleased reference id=1") +int create_and_forget_to_destroy_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("expected an initialized iter_num as arg #1") +int destroy_without_creating_fail(void *ctx) +{ + /* init with zeros to stop verifier complaining about uninit stack */ + struct bpf_iter_num iter; + + asm volatile ( + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("expected an initialized iter_num as arg #1") +int compromise_iter_w_direct_write_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + + /* directly write over first half of iter state */ + "*(u64 *)(%[iter] + 0) = r0;" + + /* (attempt to) destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("Unreleased reference id=1") +int compromise_iter_w_direct_write_and_skip_destroy_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + + /* directly write over first half of iter state */ + "*(u64 *)(%[iter] + 0) = r0;" + + /* don't destroy iter, leaking ref, which should fail */ + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("expected an initialized iter_num as arg #1") +int compromise_iter_w_helper_write_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + + /* overwrite 8th byte with bpf_probe_read_kernel() */ + "r1 = %[iter];" + "r1 += 7;" + "r2 = 1;" + "r3 = 0;" /* NULL */ + "call %[bpf_probe_read_kernel];" + + /* (attempt to) destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS, __imm(bpf_probe_read_kernel) + : __clobber_common + ); + + return 0; +} + +static __noinline void subprog_with_iter(void) +{ + struct bpf_iter_num iter; + + bpf_iter_num_new(&iter, 0, 1); + + return; +} + +SEC("?raw_tp") +__failure +/* ensure there was a call to subprog, which might happen without __noinline */ +__msg("returning from callee:") +__msg("Unreleased reference id=1") +int leak_iter_from_subprog_fail(void *ctx) +{ + subprog_with_iter(); + + return 0; +} + +SEC("?raw_tp") +__success __log_level(2) +__msg("fp-8_w=iter_num(ref_id=1,state=active,depth=0)") +int valid_stack_reuse(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + + /* now reuse same stack slots */ + + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("expected uninitialized iter_num as arg #1") +int double_create_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + /* (attempt to) create iterator again */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("expected an initialized iter_num as arg #1") +int double_destroy_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + /* (attempt to) destroy iterator again */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("expected an initialized iter_num as arg #1") +int next_without_new_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* don't create iterator and try to iterate*/ + "r1 = %[iter];" + "call %[bpf_iter_num_next];" + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("expected an initialized iter_num as arg #1") +int next_after_destroy_fail(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* create iterator */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + /* destroy iterator */ + "r1 = %[iter];" + "call %[bpf_iter_num_destroy];" + /* don't create iterator and try to iterate*/ + "r1 = %[iter];" + "call %[bpf_iter_num_next];" + : + : __imm_ptr(iter), ITER_HELPERS + : __clobber_common + ); + + return 0; +} + +SEC("?raw_tp") +__failure __msg("invalid read from stack") +int __naked read_from_iter_slot_fail(void) +{ + asm volatile ( + /* r6 points to struct bpf_iter_num on the stack */ + "r6 = r10;" + "r6 += -24;" + + /* create iterator */ + "r1 = r6;" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + + /* attemp to leak bpf_iter_num state */ + "r7 = *(u64 *)(r6 + 0);" + "r8 = *(u64 *)(r6 + 8);" + + /* destroy iterator */ + "r1 = r6;" + "call %[bpf_iter_num_destroy];" + + /* leak bpf_iter_num state */ + "r0 = r7;" + "if r7 > r8 goto +1;" + "r0 = r8;" + "exit;" + : + : ITER_HELPERS + : __clobber_common, "r6", "r7", "r8" + ); +} + +int zero; + +SEC("?raw_tp") +__failure +__flag(BPF_F_TEST_STATE_FREQ) +__msg("Unreleased reference") +int stacksafe_should_not_conflate_stack_spill_and_iter(void *ctx) +{ + struct bpf_iter_num iter; + + asm volatile ( + /* Create a fork in logic, with general setup as follows: + * - fallthrough (first) path is valid; + * - branch (second) path is invalid. + * Then depending on what we do in fallthrough vs branch path, + * we try to detect bugs in func_states_equal(), regsafe(), + * refsafe(), stack_safe(), and similar by tricking verifier + * into believing that branch state is a valid subset of + * a fallthrough state. Verifier should reject overall + * validation, unless there is a bug somewhere in verifier + * logic. + */ + "call %[bpf_get_prandom_u32];" + "r6 = r0;" + "call %[bpf_get_prandom_u32];" + "r7 = r0;" + + "if r6 > r7 goto bad;" /* fork */ + + /* spill r6 into stack slot of bpf_iter_num var */ + "*(u64 *)(%[iter] + 0) = r6;" + + "goto skip_bad;" + + "bad:" + /* create iterator in the same stack slot */ + "r1 = %[iter];" + "r2 = 0;" + "r3 = 1000;" + "call %[bpf_iter_num_new];" + + /* but then forget about it and overwrite it back to r6 spill */ + "*(u64 *)(%[iter] + 0) = r6;" + + "skip_bad:" + "goto +0;" /* force checkpoint */ + + /* corrupt stack slots, if they are really dynptr */ + "*(u64 *)(%[iter] + 0) = r6;" + : + : __imm_ptr(iter), + __imm_addr(zero), + __imm(bpf_get_prandom_u32), + __imm(bpf_dynptr_from_mem), + ITER_HELPERS + : __clobber_common, "r6", "r7" + ); + + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/iters_testmod_seq.c b/tools/testing/selftests/bpf/progs/iters_testmod_seq.c new file mode 100644 index 000000000000..3873fb6c292a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/iters_testmod_seq.c @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +struct bpf_iter_testmod_seq { + u64 :64; + u64 :64; +}; + +extern int bpf_iter_testmod_seq_new(struct bpf_iter_testmod_seq *it, s64 value, int cnt) __ksym; +extern s64 *bpf_iter_testmod_seq_next(struct bpf_iter_testmod_seq *it) __ksym; +extern void bpf_iter_testmod_seq_destroy(struct bpf_iter_testmod_seq *it) __ksym; + +const volatile __s64 exp_empty = 0 + 1; +__s64 res_empty; + +SEC("raw_tp/sys_enter") +__success __log_level(2) +__msg("fp-16_w=iter_testmod_seq(ref_id=1,state=active,depth=0)") +__msg("fp-16=iter_testmod_seq(ref_id=1,state=drained,depth=0)") +__msg("call bpf_iter_testmod_seq_destroy") +int testmod_seq_empty(const void *ctx) +{ + __s64 sum = 0, *i; + + bpf_for_each(testmod_seq, i, 1000, 0) sum += *i; + res_empty = 1 + sum; + + return 0; +} + +const volatile __s64 exp_full = 1000000; +__s64 res_full; + +SEC("raw_tp/sys_enter") +__success __log_level(2) +__msg("fp-16_w=iter_testmod_seq(ref_id=1,state=active,depth=0)") +__msg("fp-16=iter_testmod_seq(ref_id=1,state=drained,depth=0)") +__msg("call bpf_iter_testmod_seq_destroy") +int testmod_seq_full(const void *ctx) +{ + __s64 sum = 0, *i; + + bpf_for_each(testmod_seq, i, 1000, 1000) sum += *i; + res_full = sum; + + return 0; +} + +const volatile __s64 exp_truncated = 10 * 1000000; +__s64 res_truncated; + +static volatile int zero = 0; + +SEC("raw_tp/sys_enter") +__success __log_level(2) +__msg("fp-16_w=iter_testmod_seq(ref_id=1,state=active,depth=0)") +__msg("fp-16=iter_testmod_seq(ref_id=1,state=drained,depth=0)") +__msg("call bpf_iter_testmod_seq_destroy") +int testmod_seq_truncated(const void *ctx) +{ + __s64 sum = 0, *i; + int cnt = zero; + + bpf_for_each(testmod_seq, i, 10, 2000000) { + sum += *i; + cnt++; + if (cnt >= 1000000) + break; + } + res_truncated = sum; + + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/lsm.c b/tools/testing/selftests/bpf/progs/lsm.c index dc93887ed34c..fadfdd98707c 100644 --- a/tools/testing/selftests/bpf/progs/lsm.c +++ b/tools/testing/selftests/bpf/progs/lsm.c @@ -4,12 +4,12 @@ * Copyright 2020 Google LLC. */ -#include "bpf_misc.h" #include "vmlinux.h" +#include <errno.h> #include <bpf/bpf_core_read.h> #include <bpf/bpf_helpers.h> #include <bpf/bpf_tracing.h> -#include <errno.h> +#include "bpf_misc.h" struct { __uint(type, BPF_MAP_TYPE_ARRAY); diff --git a/tools/testing/selftests/bpf/progs/pyperf.h b/tools/testing/selftests/bpf/progs/pyperf.h index 6c7b1fb268d6..f2e7a31c8d75 100644 --- a/tools/testing/selftests/bpf/progs/pyperf.h +++ b/tools/testing/selftests/bpf/progs/pyperf.h @@ -7,6 +7,7 @@ #include <stdbool.h> #include <linux/bpf.h> #include <bpf/bpf_helpers.h> +#include "bpf_misc.h" #define FUNCTION_NAME_LEN 64 #define FILE_NAME_LEN 128 @@ -294,17 +295,22 @@ int __on_event(struct bpf_raw_tracepoint_args *ctx) if (ctx.done) return 0; #else -#ifdef NO_UNROLL +#if defined(USE_ITER) +/* no for loop, no unrolling */ +#elif defined(NO_UNROLL) #pragma clang loop unroll(disable) -#else -#ifdef UNROLL_COUNT +#elif defined(UNROLL_COUNT) #pragma clang loop unroll_count(UNROLL_COUNT) #else #pragma clang loop unroll(full) -#endif #endif /* NO_UNROLL */ /* Unwind python stack */ +#ifdef USE_ITER + int i; + bpf_for(i, 0, STACK_MAX_LEN) { +#else /* !USE_ITER */ for (int i = 0; i < STACK_MAX_LEN; ++i) { +#endif if (frame_ptr && get_frame_data(frame_ptr, pidData, &frame, &sym)) { int32_t new_symbol_id = *symbol_counter * 64 + cur_cpu; int32_t *symbol_id = bpf_map_lookup_elem(&symbolmap, &sym); diff --git a/tools/testing/selftests/bpf/progs/pyperf600_iter.c b/tools/testing/selftests/bpf/progs/pyperf600_iter.c new file mode 100644 index 000000000000..d62e1b200c30 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/pyperf600_iter.c @@ -0,0 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2023 Meta Platforms, Inc. and affiliates. +#define STACK_MAX_LEN 600 +#define SUBPROGS +#define NO_UNROLL +#define USE_ITER +#include "pyperf.h" diff --git a/tools/testing/selftests/bpf/progs/pyperf600_nounroll.c b/tools/testing/selftests/bpf/progs/pyperf600_nounroll.c index 6beff7502f4d..520b58c4f8db 100644 --- a/tools/testing/selftests/bpf/progs/pyperf600_nounroll.c +++ b/tools/testing/selftests/bpf/progs/pyperf600_nounroll.c @@ -2,7 +2,4 @@ // Copyright (c) 2019 Facebook #define STACK_MAX_LEN 600 #define NO_UNROLL -/* clang will not unroll at all. - * Total program size is around 2k insns - */ #include "pyperf.h" |