From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793309198; b=ARGJez1j0QWXfAMr1aihpz5Q4dr5e0HGhEZ8VSZ1LC47stj3k4FrqxzNjm7x7YgXO3bd rLJ3xMgUi+jOihWT1YEJOfuJAfpQ1DOHA0JWM9Hkh+R7KKO3ZOP5lODQeMErCjFvRGaOm +iNWlkuxrHfg6xIZXTr7jSgpRCsD9P+wvVL/dQbT6NBwFzhSyaFd+gpyeJ+wGQxTUP4do LAwaE9R0Orht2xtrG8zzYjU53rGnyLZ0qg9rKF396Q2xoHisLwbiPd2JY95YzuK/UWxFV b4njHWXnt6bkIfoSYXdy/20XHwCFI+iYXtkU2zUW1MsGIPWpv4NW2b5Ih5X9VtgDIYA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793309198; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=5blMgoBP0rICIuH/UYufNrjnwQHz9NNj7WSk+4g5PdA=; b=EixpTyMseRdvVSU5ZXcMzGlAUXd7bEhHxruRMPjMesAP0EmyIr6L5CXbOlDty97H8+fp q35ZTDyEWA85DjVrw8hiK/K7A9Kk996t4xOhFR8n54E7XIAm7A8Ufw4fO8tZ8IJb7jmW3 pwFMwUJ6TbyechT25ldvdDedYEAzrE1PEywbRZemdCBP9d+zPTNEUb8NfdRv8xfpzkbgJ wLt2Uuch2ZxZyE+GJTqM3oDdq/Wi3UyiwmDCZAtDQRQWvJMDLkpTBGmiUKL8patQqVsvJ IoTg+y8oMsSBM2sDkoiLpn2UOKWIdJxLHMwh16jz3rG35EwuSUZedWnfSYHQu882VMg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="LMlAPzA/"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BD286606A31D for ; Thu, 29 Oct 2026 21:26:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=LMlAPzA/ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0BAE01F01816; Thu, 29 Oct 2026 21:26:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793309197; bh=5blMgoBP0rICIuH/UYufNrjnwQHz9NNj7WSk+4g5PdA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=LMlAPzA/v5n9cD2RIi/AaDnxrFqTzT2B1cWbHqCSg2ea4FAkuUNaXOyDBj5fmdJOT 2/GupRcRcgyRf0Avznr31ciy3JyLx1es/iu5FDR4G7xVw7UPga5yMsun/qt/eQV9TQ cHLriz2cvO+582oJSWS6vkWmV/Ca5NrguJqwFlbfYV0cyNH+JRFEJTB4ZBSAxhChJi nLbZZ7RSXLz1tLxd9XO0fcBuqlkZmsPJakK2jr3K3DFeSrpuyQMNuzKX6PHQ/Ddvcm 1947+Bp2SuvpGbNpM3nIY95G/0vpu3jETDi+UA4oVE/y/EQMF9FWCAGzO78EBhGAdG madVkYDQuCN4w== From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann Cc: bpf@vger.kernel.org, linux-mm@kvack.org, Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi , Lorenzo Stoakes , John Fastabend , Federico Di Pierro Subject: [PATCH bpf-next 4/8] selftests/bpf: Test __srcptr kfunc arguments Date: Thu, 29 Oct 2026 22:25:47 +0100 Message-ID: <20261029212551.56964-5-jolsa@kernel.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261029212551.56964-1-jolsa@kernel.org> References: <20261029212551.56964-1-jolsa@kernel.org> X-Mailing-List: bpf@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Verify that __srcptr kfunc arguments accept read-only global data, writable stack data, and a pointer to a read-only struct of scalars. Also verify that read-only data is rejected when passed to a kfunc argument that requires writable memory. Assisted-by: Codex:GPT-6 Signed-off-by: Jiri Olsa --- .../testing/selftests/bpf/prog_tests/kfunc_call.c | 2 ++ .../testing/selftests/bpf/progs/kfunc_call_fail.c | 10 ++++++++++ .../testing/selftests/bpf/progs/kfunc_call_test.c | 14 ++++++++++++++ .../testing/selftests/bpf/test_kmods/bpf_testmod.c | 10 ++++++++++ .../selftests/bpf/test_kmods/bpf_testmod_kfunc.h | 2 ++ 5 files changed, 38 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/kfunc_call.c b/tools/testing/selftests/bpf/prog_tests/kfunc_call.c index 0063e60d6f2f..9b832c5961f5 100644 --- a/tools/testing/selftests/bpf/prog_tests/kfunc_call.c +++ b/tools/testing/selftests/bpf/prog_tests/kfunc_call.c @@ -63,6 +63,7 @@ static struct kfunc_test_params kfunc_tests[] = { */ SYSCALL_NULL_CTX_FAIL(kfunc_syscall_test_fail, -EINVAL, "processed 4 insns"), SYSCALL_NULL_CTX_FAIL(kfunc_syscall_test_null_fail, -EINVAL, "processed 4 insns"), + TC_FAIL(kfunc_call_test_mem_len_fail_readonly, 0, "write into map forbidden"), TC_FAIL(kfunc_call_test_get_mem_fail_rdonly, 0, "R0 cannot write into rdonly_mem"), TC_FAIL(kfunc_call_test_get_mem_fail_use_after_free, 0, "invalid mem access 'scalar'"), TC_FAIL(kfunc_call_test_get_mem_fail_oob, 0, "min value is outside of the allowed memory range"), @@ -82,6 +83,7 @@ static struct kfunc_test_params kfunc_tests[] = { TC_TEST(kfunc_call_test5_asm, 0), TC_TEST(kfunc_call_test_ref_btf_id, 0), TC_TEST(kfunc_call_test_get_mem, 42), + TC_TEST(kfunc_call_test_srcptr, 0), SYSCALL_TEST(kfunc_syscall_test, 0), SYSCALL_NULL_CTX_TEST(kfunc_syscall_test_null, 0), TC_TEST(kfunc_call_test_static_unused_arg, 0), diff --git a/tools/testing/selftests/bpf/progs/kfunc_call_fail.c b/tools/testing/selftests/bpf/progs/kfunc_call_fail.c index 7e93f7fb1329..1ab85faaf8db 100644 --- a/tools/testing/selftests/bpf/progs/kfunc_call_fail.c +++ b/tools/testing/selftests/bpf/progs/kfunc_call_fail.c @@ -4,6 +4,8 @@ #include #include "../test_kmods/bpf_testmod_kfunc.h" +static const char mem_len_rodata[] = "read-only data"; + static struct bpf_spin_lock kfunc_call_lock SEC(".data.A"); SEC("?tc") @@ -47,6 +49,14 @@ int kfunc_syscall_test_null_fail(struct syscall_test_args *args) return 0; } +SEC("?tc") +int kfunc_call_test_mem_len_fail_readonly(struct __sk_buff *skb) +{ + bpf_kfunc_call_test_mem_len_pass1((void *)mem_len_rodata, + sizeof(mem_len_rodata)); + return 0; +} + SEC("?tc") int kfunc_call_test_get_mem_fail_rdonly(struct __sk_buff *skb) { diff --git a/tools/testing/selftests/bpf/progs/kfunc_call_test.c b/tools/testing/selftests/bpf/progs/kfunc_call_test.c index 8e6560c31e78..fc862fce3f2f 100644 --- a/tools/testing/selftests/bpf/progs/kfunc_call_test.c +++ b/tools/testing/selftests/bpf/progs/kfunc_call_test.c @@ -5,6 +5,9 @@ #include "bpf_misc.h" #include "../test_kmods/bpf_testmod_kfunc.h" +static const char srcptr_rodata[] = "read-only source"; +static const struct prog_test_pass1 srcptr_struct_rodata = { .x0 = 1 }; + static struct bpf_spin_lock kfunc_call_lock SEC(".data.A"); SEC("tc") @@ -208,6 +211,17 @@ int kfunc_call_test_pass(struct __sk_buff *skb) return 0; } +SEC("tc") +int kfunc_call_test_srcptr(struct __sk_buff *skb) +{ + char stack_data[] = "read-write source"; + + bpf_kfunc_call_test_srcptr(srcptr_rodata, sizeof(srcptr_rodata)); + bpf_kfunc_call_test_srcptr(stack_data, sizeof(stack_data)); + bpf_kfunc_call_test_srcptr_struct(&srcptr_struct_rodata); + return 0; +} + struct syscall_test_args { __u8 data[16]; size_t size; diff --git a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c index 6380f52f4dd2..87967c7236a7 100644 --- a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c +++ b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c @@ -1024,6 +1024,8 @@ BTF_ID_FLAGS(func, bpf_kfunc_arena_args5_test) BTF_ID_FLAGS(func, bpf_kfunc_arena_stack_arg_test) BTF_ID_FLAGS(func, bpf_kfunc_arena_mixed_test) BTF_ID_FLAGS(func, bpf_kfunc_call_test_mem_len_pass1) +BTF_ID_FLAGS(func, bpf_kfunc_call_test_srcptr) +BTF_ID_FLAGS(func, bpf_kfunc_call_test_srcptr_struct) BTF_ID_FLAGS(func, bpf_kfunc_dynptr_test) BTF_ID_FLAGS(func, bpf_kfunc_nested_acquire_nonzero_offset_test, KF_ACQUIRE) BTF_ID_FLAGS(func, bpf_kfunc_nested_acquire_zero_offset_test, KF_ACQUIRE) @@ -1527,6 +1529,14 @@ __bpf_kfunc void bpf_kfunc_call_test_mem_len_pass1(void *mem, int mem__sz) { } +__bpf_kfunc void bpf_kfunc_call_test_srcptr(const void *src__srcptr, int src__sz) +{ +} + +__bpf_kfunc void bpf_kfunc_call_test_srcptr_struct(const struct prog_test_pass1 *p__srcptr) +{ +} + __bpf_kfunc void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len) { } 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 3b810f1e438f..6de080682618 100644 --- a/tools/testing/selftests/bpf/test_kmods/bpf_testmod_kfunc.h +++ b/tools/testing/selftests/bpf/test_kmods/bpf_testmod_kfunc.h @@ -198,6 +198,8 @@ void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym; void bpf_kfunc_call_test_ref(struct prog_test_ref_kfunc *p) __ksym; void bpf_kfunc_call_test_mem_len_pass1(void *mem, int len) __ksym; +void bpf_kfunc_call_test_srcptr(const void *src__srcptr, int src__sz) __ksym; +void bpf_kfunc_call_test_srcptr_struct(const struct prog_test_pass1 *p__srcptr) __ksym; __u64 bpf_kfunc_arena_arg_test(__u64 *val__arena) __ksym; __u64 bpf_kfunc_arena_cap_test(__u64 *val__arena) __ksym; __u64 bpf_kfunc_arena_cap_nullable_test(__u64 *val__arena__nullable) __ksym; -- 2.54.0