diff --git a/include/linux/filter.h b/include/linux/filter.h index 2ce57645f3cd..0367a75f873b 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -1099,7 +1099,6 @@ static inline void bpf_get_prog_name(const struct bpf_prog *prog, char *sym) #endif /* CONFIG_BPF_JIT */ -void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp); void bpf_prog_kallsyms_del_all(struct bpf_prog *fp); #define BPF_ANC BIT(15) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 66088a9e9b9e..ef0e1e3e66f4 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -502,7 +502,7 @@ int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt) return WARN_ON_ONCE(bpf_adj_branches(prog, off, off + cnt, off, false)); } -void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp) +static void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp) { int i; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 82eabd4e38ad..bcfc362de4f2 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1332,18 +1332,26 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu) bpf_prog_free(aux->prog); } +static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred) +{ + bpf_prog_kallsyms_del_all(prog); + btf_put(prog->aux->btf); + kvfree(prog->aux->func_info); + bpf_prog_free_linfo(prog); + + if (deferred) + call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); + else + __bpf_prog_put_rcu(&prog->aux->rcu); +} + static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) { if (atomic_dec_and_test(&prog->aux->refcnt)) { perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); /* bpf_prog_free_id() must be called first */ bpf_prog_free_id(prog, do_idr_lock); - bpf_prog_kallsyms_del_all(prog); - btf_put(prog->aux->btf); - kvfree(prog->aux->func_info); - bpf_prog_free_linfo(prog); - - call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); + __bpf_prog_put_noref(prog, true); } } @@ -1741,11 +1749,12 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr) return err; free_used_maps: - bpf_prog_free_linfo(prog); - kvfree(prog->aux->func_info); - btf_put(prog->aux->btf); - bpf_prog_kallsyms_del_subprogs(prog); - free_used_maps(prog->aux); + /* In case we have subprogs, we need to wait for a grace + * period before we can tear down JIT memory since symbols + * are already exposed under kallsyms. + */ + __bpf_prog_put_noref(prog, prog->aux->func_cnt); + return err; free_prog: bpf_prog_uncharge_memlock(prog); free_prog_sec: