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Invalidate the original dynptr should not prevent the program from using the slice derived from the cloned dynptr. Signed-off-by: Amery Hung --- .../selftests/bpf/prog_tests/bpf_qdisc.c | 14 ++++ .../bpf/progs/bpf_qdisc_dynptr_clone.c | 69 +++++++++++++++++++ 2 files changed, 83 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/bpf_qdisc_dynptr_clone.c diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_qdisc.c b/tools/testing/selftests/bpf/prog_tests/bpf_qdisc.c index ec5b346138c5..ba14738c509b 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_qdisc.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_qdisc.c @@ -11,6 +11,7 @@ #include "bpf_qdisc_fail__invalid_dynptr.skel.h" #include "bpf_qdisc_fail__invalid_dynptr_slice.skel.h" #include "bpf_qdisc_fail__invalid_dynptr_cross_frame.skel.h" +#include "bpf_qdisc_dynptr_clone.skel.h" #define LO_IFINDEX 1 @@ -186,6 +187,17 @@ static void test_invalid_dynptr_cross_frame(void) bpf_qdisc_fail__invalid_dynptr_cross_frame__destroy(skel); } +static void test_dynptr_clone(void) +{ + struct bpf_qdisc_dynptr_clone *skel; + + skel = bpf_qdisc_dynptr_clone__open_and_load(); + if (!ASSERT_OK_PTR(skel, "bpf_qdisc_dynptr_clone__open_and_load")) + return; + + bpf_qdisc_dynptr_clone__destroy(skel); +} + static int get_default_qdisc(char *qdisc_name) { FILE *f; @@ -259,6 +271,8 @@ void test_ns_bpf_qdisc(void) test_invalid_dynptr_slice(); if (test__start_subtest("invalid_dynptr_cross_frame")) test_invalid_dynptr_cross_frame(); + if (test__start_subtest("dynptr_clone")) + test_dynptr_clone(); } void serial_test_bpf_qdisc_default(void) diff --git a/tools/testing/selftests/bpf/progs/bpf_qdisc_dynptr_clone.c b/tools/testing/selftests/bpf/progs/bpf_qdisc_dynptr_clone.c new file mode 100644 index 000000000000..f23581e19da1 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_qdisc_dynptr_clone.c @@ -0,0 +1,69 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include "bpf_experimental.h" +#include "bpf_qdisc_common.h" + +char _license[] SEC("license") = "GPL"; + +int proto; + +SEC("struct_ops") +int BPF_PROG(bpf_qdisc_test_enqueue, struct sk_buff *skb, struct Qdisc *sch, + struct bpf_sk_buff_ptr *to_free) +{ + struct bpf_dynptr ptr, ptr_clone; + struct ethhdr *hdr; + + bpf_dynptr_from_skb((struct __sk_buff *)skb, 0, &ptr); + + bpf_dynptr_clone(&ptr, &ptr_clone); + + hdr = bpf_dynptr_slice(&ptr_clone, 0, NULL, sizeof(*hdr)); + if (!hdr) { + bpf_qdisc_skb_drop(skb, to_free); + return NET_XMIT_DROP; + } + + *(int *)&ptr = 0; + + proto = hdr->h_proto; + + bpf_qdisc_skb_drop(skb, to_free); + + return NET_XMIT_DROP; +} + +SEC("struct_ops") +struct sk_buff *BPF_PROG(bpf_qdisc_test_dequeue, struct Qdisc *sch) +{ + return NULL; +} + +SEC("struct_ops") +int BPF_PROG(bpf_qdisc_test_init, struct Qdisc *sch, struct nlattr *opt, + struct netlink_ext_ack *extack) +{ + return 0; +} + +SEC("struct_ops") +void BPF_PROG(bpf_qdisc_test_reset, struct Qdisc *sch) +{ +} + +SEC("struct_ops") +void BPF_PROG(bpf_qdisc_test_destroy, struct Qdisc *sch) +{ +} + +SEC(".struct_ops") +struct Qdisc_ops test = { + .enqueue = (void *)bpf_qdisc_test_enqueue, + .dequeue = (void *)bpf_qdisc_test_dequeue, + .init = (void *)bpf_qdisc_test_init, + .reset = (void *)bpf_qdisc_test_reset, + .destroy = (void *)bpf_qdisc_test_destroy, + .id = "bpf_qdisc_test", +}; + -- 2.47.3