diff --git a/include/linux/bpf.h b/include/linux/bpf.h index e066f44a9c05..7bfc28673124 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1523,6 +1523,7 @@ int bpf_trampoline_multi_attach(struct bpf_prog *prog, u32 *ids, struct bpf_tracing_multi_link *link); int bpf_trampoline_multi_detach(struct bpf_prog *prog, struct bpf_tracing_multi_link *link); +void bpf_trampoline_set_flags(struct bpf_trampoline *tr, u32 flags); /* * When the architecture supports STATIC_CALL replace the bpf_dispatcher_fn @@ -1646,6 +1647,7 @@ static inline int bpf_trampoline_multi_detach(struct bpf_prog *prog, { return -ENOTSUPP; } +static inline void bpf_trampoline_set_flags(struct bpf_trampoline *tr, u32 flags) {} #endif struct bpf_func_info_aux { diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c index 6eadf64f7ec9..129d07db117e 100644 --- a/kernel/bpf/trampoline.c +++ b/kernel/bpf/trampoline.c @@ -670,6 +670,13 @@ static struct bpf_tramp_image *bpf_tramp_image_alloc(u64 key, int size) return ERR_PTR(err); } +void bpf_trampoline_set_flags(struct bpf_trampoline *tr, u32 flags) +{ + trampoline_lock(tr); + tr->flags |= flags; + trampoline_unlock(tr); +} + static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mutex, const struct bpf_trampoline_ops *ops, void *data) { diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 52be0a118cce..66d8d9eaec05 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -19523,7 +19523,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env) return -ENOMEM; if (tgt_prog && tgt_prog->aux->tail_call_reachable) - tr->flags = BPF_TRAMP_F_TAIL_CALL_CTX; + bpf_trampoline_set_flags(tr, BPF_TRAMP_F_TAIL_CALL_CTX); prog->aux->dst_trampoline = tr; return 0; diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c index c66037162da5..c5c9d6c359bb 100644 --- a/tools/testing/selftests/bpf/prog_tests/tailcalls.c +++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c @@ -13,6 +13,8 @@ #include "tailcall_cgrp_storage.skel.h" #include "tailcall_sleepable.skel.h" #include "tailcall_callback.skel.h" +#include "tailcall_bpf2bpf2.skel.h" +#include "tailcall_bpf2bpf_fexit.skel.h" /* test_tailcall_1 checks basic functionality by patching multiple locations * in a single program for a single tail call slot with nop->jmp, jmp->nop @@ -1907,6 +1909,50 @@ static void test_tailcall_callback(void) RUN_TESTS(tailcall_callback); } +static void test_tailcall_bpf2bpf_fexit_links(void) +{ + struct tailcall_bpf2bpf_fexit *skel1 = NULL, *skel2 = NULL; + struct tailcall_bpf2bpf2 *skel_tc; + int err, prog_fd; + + skel_tc = tailcall_bpf2bpf2__open_and_load(); + if (!ASSERT_OK_PTR(skel_tc, "tailcall_bpf2bpf2__open_and_load")) + return; + + skel1 = tailcall_bpf2bpf_fexit__open(); + if (!ASSERT_OK_PTR(skel1, "tailcall_bpf2bpf_fexit__open")) + goto out; + + prog_fd = bpf_program__fd(skel_tc->progs.classifier_0); + err = bpf_program__set_attach_target(skel1->progs.fexit, prog_fd, "subprog_tail"); + if (!ASSERT_OK(err, "bpf_program__set_attach_target")) + goto out; + + err = tailcall_bpf2bpf_fexit__load(skel1); + if (!ASSERT_OK(err, "tailcall_bpf2bpf_fexit__load")) + goto out; + + skel1->links.fexit = bpf_program__attach_trace(skel1->progs.fexit); + if (!ASSERT_OK_PTR(skel1->links.fexit, "bpf_program__attach_trace")) + goto out; + + skel2 = tailcall_bpf2bpf_fexit__open(); + if (!ASSERT_OK_PTR(skel2, "tailcall_bpf2bpf_fexit__open")) + goto out; + + err = bpf_program__set_attach_target(skel2->progs.fexit, prog_fd, "subprog_tail"); + if (!ASSERT_OK(err, "bpf_program__set_attach_target")) + goto out; + + err = tailcall_bpf2bpf_fexit__load(skel2); + ASSERT_OK(err, "tailcall_bpf2bpf_fexit__load"); + +out: + tailcall_bpf2bpf_fexit__destroy(skel1); + tailcall_bpf2bpf_fexit__destroy(skel2); + tailcall_bpf2bpf2__destroy(skel_tc); +} + void test_tailcalls(void) { if (test__start_subtest("tailcall_1")) @@ -1974,4 +2020,6 @@ void test_tailcalls(void) if (test__start_subtest("tailcall_cgrp_storage_no_storage_bridge")) test_tailcall_cgrp_storage_no_storage_bridge(); test_tailcall_callback(); + if (test__start_subtest("tailcall_bpf2bpf_fexit_links")) + test_tailcall_bpf2bpf_fexit_links(); }