// SPDX-License-Identifier: GPL-2.0 /* * Test weak ksyms. * * Copyright (c) 2021 Google */ #include "vmlinux.h" #include <bpf/bpf_helpers.h> int out__existing_typed = -1; __u64 out__existing_typeless = -1; __u64 out__non_existent_typeless = -1; __u64 out__non_existent_typed = -1; /* existing weak symbols */ /* test existing weak symbols can be resolved. */ extern const struct rq runqueues __ksym __weak; /* typed */ extern const void bpf_prog_active __ksym __weak; /* typeless */ struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym __weak; void bpf_testmod_test_mod_kfunc(int i) __ksym __weak; /* non-existent weak symbols. */ /* typeless symbols, default to zero. */ extern const void bpf_link_fops1 __ksym __weak; /* typed symbols, default to zero. */ extern const int bpf_link_fops2 __ksym __weak; void invalid_kfunc(void) __ksym __weak; SEC("raw_tp/sys_enter") int pass_handler(const void *ctx) { struct rq *rq; /* tests existing symbols. */ rq = (struct rq *)bpf_per_cpu_ptr(&runqueues, 0); if (rq && bpf_ksym_exists(&runqueues)) out__existing_typed = rq->cpu; out__existing_typeless = (__u64)&bpf_prog_active; /* tests non-existent symbols. */ out__non_existent_typeless = (__u64)&bpf_link_fops1; /* tests non-existent symbols. */ out__non_existent_typed = (__u64)&bpf_link_fops2; if (&bpf_link_fops2) /* can't happen */ out__non_existent_typed = (__u64)bpf_per_cpu_ptr(&bpf_link_fops2, 0); if (!bpf_ksym_exists(bpf_task_acquire)) /* dead code won't be seen by the verifier */ bpf_task_acquire(0); if (!bpf_ksym_exists(bpf_testmod_test_mod_kfunc)) /* dead code won't be seen by the verifier */ bpf_testmod_test_mod_kfunc(0); if (bpf_ksym_exists(invalid_kfunc)) /* dead code won't be seen by the verifier */ invalid_kfunc(); return 0; } char _license[] SEC("license") = "GPL";