diff --git a/tools/testing/selftests/bpf/prog_tests/test_struct_ops_arena.c b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_arena.c new file mode 100644 index 000000000000..323d707c543f --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/test_struct_ops_arena.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2026 Meta Platforms, Inc. and affiliates. */ +#include + +#include "struct_ops_arena.skel.h" +#include "struct_ops_arena_fail.skel.h" + +#if defined(__x86_64__) +/* + * Attach callbacks with __arena and __arena__nullable arguments and drive + * them through the bpf_testmod_ops3_call_test_arena*() kfuncs. + */ +static void arena_arg(void) +{ + LIBBPF_OPTS(bpf_test_run_opts, topts); + struct struct_ops_arena *skel; + struct bpf_link *link = NULL; + int err; + + skel = struct_ops_arena__open_and_load(); + if (!ASSERT_OK_PTR(skel, "struct_ops_arena__open_and_load")) + return; + + link = bpf_map__attach_struct_ops(skel->maps.testmod_arena); + if (!ASSERT_OK_PTR(link, "attach_struct_ops")) + goto out; + + err = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.trigger), + &topts); + ASSERT_OK(err, "test_run"); + ASSERT_EQ(topts.retval, 0, "trigger_retval"); + +out: + bpf_link__destroy(link); + struct_ops_arena__destroy(skel); +} + +/* + * A program with no arena cannot attach to a member with an __arena + * argument. + */ +static void arena_arg_fail(void) +{ + struct struct_ops_arena_fail *skel; + + skel = struct_ops_arena_fail__open_and_load(); + if (ASSERT_ERR_PTR(skel, "struct_ops_arena_fail__open_and_load")) + return; + + struct_ops_arena_fail__destroy(skel); +} +#endif + +/* + * Serialized because it attaches the singleton bpf_testmod_ops3, which + * test_struct_ops_private_stack also attaches; registering it twice fails + * with -EEXIST. + */ +void serial_test_struct_ops_arena(void) +{ + /* + * Arena struct_ops arguments need JIT support, currently x86-64 only. + * Elsewhere verification fails with "JIT does not support arena + * arguments", so the programs cannot even load. + */ +#if defined(__x86_64__) + if (test__start_subtest("arena_arg")) + arena_arg(); + if (test__start_subtest("arena_arg_fail")) + arena_arg_fail(); +#else + test__skip(); +#endif +} diff --git a/tools/testing/selftests/bpf/progs/struct_ops_arena.c b/tools/testing/selftests/bpf/progs/struct_ops_arena.c new file mode 100644 index 000000000000..40c856a748d2 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/struct_ops_arena.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2026 Meta Platforms, Inc. and affiliates. */ + +#define BPF_NO_KFUNC_PROTOTYPES +#include +#include +#include "bpf_experimental.h" +#include +#include "../test_kmods/bpf_testmod.h" +#include "../test_kmods/bpf_testmod_kfunc.h" + +char _license[] SEC("license") = "GPL"; + +struct { + __uint(type, BPF_MAP_TYPE_ARENA); + __uint(map_flags, BPF_F_MMAPABLE); + /* page 0 hosts the arena globals, page 1 is for allocations */ + __uint(max_entries, 2); +} arena SEC(".maps"); + +/* also associates the callbacks with the arena */ +u64 __arena arena_touch; +/* raw value of the last __arena ctx argument, captured by test_arena_cb */ +u64 __arena cb_ptr_val; + +SEC("struct_ops/test_arena") +int test_arena_cb(unsigned long long *ctx) +{ + u64 __arena *ptr = (u64 __arena *)ctx[0]; + + arena_touch++; + cb_ptr_val = ctx[0]; + *ptr += 1; + return 0; +} + +SEC("struct_ops/test_arena_nullable") +int test_arena_nullable_cb(unsigned long long *ctx) +{ + u64 __arena *ptr = (u64 __arena *)ctx[0]; + + arena_touch++; + if (!ptr) + return 0xbee; + *ptr += 1; + return 0; +} + +SEC(".struct_ops.link") +struct bpf_testmod_ops3 testmod_arena = { + .test_arena = (void *)test_arena_cb, + .test_arena_nullable = (void *)test_arena_nullable_cb, +}; + +SEC("syscall") +int trigger(void *ctx) +{ +#if defined(__BPF_FEATURE_ADDR_SPACE_CAST) + u64 __arena *val; + int ret; + + val = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0); + if (!val) + return 1; + + *val = 41; + ret = bpf_testmod_ops3_call_test_arena((u64 *)val); + if (ret) + return 2; + if (*val != 42) + return 3; + + /* + * The callback must have seen exactly (u32)(kaddr - kern_vm_start), + * which is the arena offset of val with the upper 32 bits clear. + */ + if (cb_ptr_val != (u32)(u64)val) + return 4; + + ret = bpf_testmod_ops3_call_test_arena_nullable((u64 *)val); + if (ret) + return 5; + if (*val != 43) + return 6; + + /* NULL survives the nullable kfunc and the trampoline as NULL */ + ret = bpf_testmod_ops3_call_test_arena_nullable(NULL); + if (ret != 0xbee) + return 7; + + bpf_arena_free_pages(&arena, (void __arena *)val, 1); +#endif + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/struct_ops_arena_fail.c b/tools/testing/selftests/bpf/progs/struct_ops_arena_fail.c new file mode 100644 index 000000000000..1c0ec727d637 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/struct_ops_arena_fail.c @@ -0,0 +1,20 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2026 Meta Platforms, Inc. and affiliates. */ + +#include +#include +#include "../test_kmods/bpf_testmod.h" + +char _license[] SEC("license") = "GPL"; + +/* No arena in the program: attaching to test_arena must be rejected. */ +SEC("struct_ops/test_arena") +int test_arena_no_arena(unsigned long long *ctx) +{ + return 0; +} + +SEC(".struct_ops.link") +struct bpf_testmod_ops3 testmod_arena_fail = { + .test_arena = (void *)test_arena_no_arena, +}; diff --git a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c index 2291bb466517..1e6d632c6f83 100644 --- a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c +++ b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c @@ -385,9 +385,21 @@ static int bpf_testmod_test_4(void) return 0; } +static int bpf_testmod_ops3__test_arena(u64 *ptr__arena) +{ + return 0; +} + +static int bpf_testmod_ops3__test_arena_nullable(u64 *ptr__arena__nullable) +{ + return 0; +} + static struct bpf_testmod_ops3 __bpf_testmod_ops3 = { .test_1 = bpf_testmod_test_3, .test_2 = bpf_testmod_test_4, + .test_arena = bpf_testmod_ops3__test_arena, + .test_arena_nullable = bpf_testmod_ops3__test_arena_nullable, }; static void bpf_testmod_test_struct_ops3(void) @@ -406,6 +418,16 @@ __bpf_kfunc void bpf_testmod_ops3_call_test_2(void) st_ops3->test_2(); } +__bpf_kfunc int bpf_testmod_ops3_call_test_arena(u64 *ptr__arena) +{ + return st_ops3->test_arena(ptr__arena); +} + +__bpf_kfunc int bpf_testmod_ops3_call_test_arena_nullable(u64 *ptr__arena__nullable) +{ + return st_ops3->test_arena_nullable(ptr__arena__nullable); +} + struct bpf_testmod_btf_type_tag_1 { int a; }; @@ -814,6 +836,8 @@ BTF_ID_FLAGS(func, bpf_testmod_ctx_create, KF_ACQUIRE | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_testmod_ctx_release, KF_RELEASE) BTF_ID_FLAGS(func, bpf_testmod_ops3_call_test_1) BTF_ID_FLAGS(func, bpf_testmod_ops3_call_test_2) +BTF_ID_FLAGS(func, bpf_testmod_ops3_call_test_arena) +BTF_ID_FLAGS(func, bpf_testmod_ops3_call_test_arena_nullable) BTF_ID_FLAGS(func, bpf_kfunc_get_default_trusted_ptr_test); BTF_ID_FLAGS(func, bpf_kfunc_put_default_trusted_ptr_test); BTF_KFUNCS_END(bpf_testmod_common_kfunc_ids) diff --git a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.h b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.h index 863fd10f1619..c367ec856776 100644 --- a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.h +++ b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.h @@ -106,6 +106,9 @@ struct bpf_testmod_ops2 { struct bpf_testmod_ops3 { int (*test_1)(void); int (*test_2)(void); + /* Used to test arena pointer arguments. */ + int (*test_arena)(u64 *ptr); + int (*test_arena_nullable)(u64 *ptr); }; struct st_ops_args { diff --git a/tools/testing/selftests/bpf/test_kmods/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/test_kmods/bpf_testmod_kfunc.h index 453bfd94154f..ea1747e2ad1f 100644 --- a/tools/testing/selftests/bpf/test_kmods/bpf_testmod_kfunc.h +++ b/tools/testing/selftests/bpf/test_kmods/bpf_testmod_kfunc.h @@ -120,6 +120,8 @@ u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused) __ksym; #endif void bpf_testmod_test_mod_kfunc(int i) __ksym; +int bpf_testmod_ops3_call_test_arena(__u64 *ptr__arena) __ksym; +int bpf_testmod_ops3_call_test_arena_nullable(__u64 *ptr__arena__nullable) __ksym; __u64 bpf_kfunc_call_test1(struct sock *sk, __u32 a, __u64 b, __u32 c, __u64 d) __ksym;