From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EBFAFC64EC7 for ; Tue, 28 Feb 2023 17:07:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229516AbjB1RH4 (ORCPT ); Tue, 28 Feb 2023 12:07:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229509AbjB1RHz (ORCPT ); Tue, 28 Feb 2023 12:07:55 -0500 Received: from mail-qt1-f170.google.com (mail-qt1-f170.google.com [209.85.160.170]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA62B171C; Tue, 28 Feb 2023 09:07:53 -0800 (PST) Received: by mail-qt1-f170.google.com with SMTP id y10so6595687qtj.2; Tue, 28 Feb 2023 09:07:53 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=H1STn0ChdpEyosfrTpw212glnukdXlJ1S7+QzeAmafM=; b=WXFfDLlAwX3FrCAwdo0aZi2LVOauhR8NraxSs85sQ/fyICDgkMSSBmDkaLG2moDgN6 KkJ+BKex5gVoC7K+7TqilyjN0+iAUydFCVG9fFm//Sj1n7a53/e7S5Qz7QjC+5uw4jEf qO7h02C0p1En3UYxc9d4mUlInwy688a0nn9j5L/fOVF5M4BjFZiGw7xSpI15gKSuW4eV EgbVgOAc49sR/1kJTm79iKZyWca2pVKxkkBQWp20BtPu/90K2wezfIQJs+TouV7bz0wF +0fcWSh+3IMeftmqdQS9eWqRicVp9MF0Pt3cTvXHqCxZ2qin8NfKJurGqqGv4yLafNrw htng== X-Gm-Message-State: AO0yUKVq6pQBiyMvnuqyAHHBAzfx4bdHdueFGf7oKLgoCnUvaEMu2meG 0axwPEM0WbvYGkl9GHuEne0= X-Google-Smtp-Source: AK7set8wMUPDT6/cRynARy5O28d62ggPAXrkeZmKMTl1dGmzImpas3RmWusxvGmF2zA/7FJEyO5kZg== X-Received: by 2002:a05:622a:1101:b0:3bf:ca04:3bc6 with SMTP id e1-20020a05622a110100b003bfca043bc6mr6006053qty.9.1677604072687; Tue, 28 Feb 2023 09:07:52 -0800 (PST) Received: from maniforge ([2620:10d:c091:480::1:f172]) by smtp.gmail.com with ESMTPSA id i14-20020ac8764e000000b003b86b962030sm6728644qtr.72.2023.02.28.09.07.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Feb 2023 09:07:52 -0800 (PST) Date: Tue, 28 Feb 2023 11:07:49 -0600 From: David Vernet To: Alexei Starovoitov Cc: davem@davemloft.net, daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org, davemarchevsky@meta.com, tj@kernel.org, memxor@gmail.com, netdev@vger.kernel.org, bpf@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH v3 bpf-next 5/5] selftests/bpf: Tweak cgroup kfunc test. Message-ID: References: <20230228040121.94253-1-alexei.starovoitov@gmail.com> <20230228040121.94253-6-alexei.starovoitov@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230228040121.94253-6-alexei.starovoitov@gmail.com> User-Agent: Mutt/2.2.9 (2022-11-12) Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Mon, Feb 27, 2023 at 08:01:21PM -0800, Alexei Starovoitov wrote: > From: Alexei Starovoitov > > Adjust cgroup kfunc test to dereference RCU protected cgroup pointer > as PTR_TRUSTED and pass into KF_TRUSTED_ARGS kfunc. > > Signed-off-by: Alexei Starovoitov This LGTM, but I noticed that another cgrp test was failing with this patch set: [root@archbig bpf]# ./test_progs -t cgrp_local_storage/recursion test_cgrp_local_storage:PASS:join_cgroup /cgrp_local_storage 0 nsec libbpf: prog 'on_lookup': BPF program load failed: Permission denied libbpf: prog 'on_lookup': -- BEGIN PROG LOAD LOG -- reg type unsupported for arg#0 function on_lookup#16 0: R1=ctx(off=0,imm=0) R10=fp0 ; struct task_struct *task = bpf_get_current_task_btf(); 0: (85) call bpf_get_current_task_btf#158 ; R0_w=trusted_ptr_task_struct(off=0,imm=0) 1: (bf) r6 = r0 ; R0_w=trusted_ptr_task_struct(off=0,imm=0) R6_w=trusted_ptr_task_struct(off=0,imm=0) ; bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp); 2: (79) r1 = *(u64 *)(r6 +2296) ; R1_w=rcu_ptr_or_null_css_set(off=0,imm=0) R6_w=trusted_ptr_task_struct(off=0,imm=0) ; bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp); 3: (79) r2 = *(u64 *)(r1 +120) R1 invalid mem access 'rcu_ptr_or_null_' processed 4 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 -- END PROG LOAD LOG -- libbpf: prog 'on_lookup': failed to load: -13 libbpf: failed to load object 'cgrp_ls_recursion' libbpf: failed to load BPF skeleton 'cgrp_ls_recursion': -13 test_recursion:FAIL:skel_open_and_load unexpected error: -13 #43/3 cgrp_local_storage/recursion:FAIL #43 cgrp_local_storage:FAIL All error logs: test_cgrp_local_storage:PASS:join_cgroup /cgrp_local_storage 0 nsec libbpf: prog 'on_lookup': BPF program load failed: Permission denied libbpf: prog 'on_lookup': -- BEGIN PROG LOAD LOG -- reg type unsupported for arg#0 function on_lookup#16 0: R1=ctx(off=0,imm=0) R10=fp0 ; struct task_struct *task = bpf_get_current_task_btf(); 0: (85) call bpf_get_current_task_btf#158 ; R0_w=trusted_ptr_task_struct(off=0,imm=0) 1: (bf) r6 = r0 ; R0_w=trusted_ptr_task_struct(off=0,imm=0) R6_w=trusted_ptr_task_struct(off=0,imm=0) ; bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp); 2: (79) r1 = *(u64 *)(r6 +2296) ; R1_w=rcu_ptr_or_null_css_set(off=0,imm=0) R6_w=trusted_ptr_task_struct(off=0,imm=0) ; bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp); 3: (79) r2 = *(u64 *)(r1 +120) R1 invalid mem access 'rcu_ptr_or_null_' processed 4 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 -- END PROG LOAD LOG -- libbpf: prog 'on_lookup': failed to load: -13 libbpf: failed to load object 'cgrp_ls_recursion' libbpf: failed to load BPF skeleton 'cgrp_ls_recursion': -13 test_recursion:FAIL:skel_open_and_load unexpected error: -13 #43/3 cgrp_local_storage/recursion:FAIL #43 cgrp_local_storage:FAIL Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED [root@archbig bpf]# The ptr type looks correct, so I assumed that the arg type for the proto needed to be updated to expect NULL. This doesn't seem to fix it though: diff --git a/kernel/bpf/bpf_cgrp_storage.c b/kernel/bpf/bpf_cgrp_storage.c index 6cdf6d9ed91d..9d5d47c8e820 100644 --- a/kernel/bpf/bpf_cgrp_storage.c +++ b/kernel/bpf/bpf_cgrp_storage.c @@ -241,6 +241,6 @@ const struct bpf_func_proto bpf_cgrp_storage_delete_proto = { .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, - .arg2_type = ARG_PTR_TO_BTF_ID, + .arg2_type = ARG_PTR_TO_BTF_ID_OR_NULL, .arg2_btf_id = &bpf_cgroup_btf_id[0], }; > --- > tools/testing/selftests/bpf/progs/cgrp_kfunc_failure.c | 2 +- > tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c | 7 ++++++- > 2 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/tools/testing/selftests/bpf/progs/cgrp_kfunc_failure.c b/tools/testing/selftests/bpf/progs/cgrp_kfunc_failure.c > index 4ad7fe24966d..d5a53b5e708f 100644 > --- a/tools/testing/selftests/bpf/progs/cgrp_kfunc_failure.c > +++ b/tools/testing/selftests/bpf/progs/cgrp_kfunc_failure.c > @@ -205,7 +205,7 @@ int BPF_PROG(cgrp_kfunc_get_unreleased, struct cgroup *cgrp, const char *path) > } > > SEC("tp_btf/cgroup_mkdir") > -__failure __msg("arg#0 is untrusted_ptr_or_null_ expected ptr_ or socket") > +__failure __msg("bpf_cgroup_release expects refcounted") > int BPF_PROG(cgrp_kfunc_release_untrusted, struct cgroup *cgrp, const char *path) > { > struct __cgrps_kfunc_map_value *v; > diff --git a/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c b/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c > index 42e13aebdd62..85becaa8573b 100644 > --- a/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c > +++ b/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c > @@ -61,7 +61,7 @@ int BPF_PROG(test_cgrp_acquire_leave_in_map, struct cgroup *cgrp, const char *pa > SEC("tp_btf/cgroup_mkdir") > int BPF_PROG(test_cgrp_xchg_release, struct cgroup *cgrp, const char *path) > { > - struct cgroup *kptr; > + struct cgroup *kptr, *cg; > struct __cgrps_kfunc_map_value *v; > long status; > > @@ -80,6 +80,11 @@ int BPF_PROG(test_cgrp_xchg_release, struct cgroup *cgrp, const char *path) > return 0; > } > > + kptr = v->cgrp; > + cg = bpf_cgroup_ancestor(kptr, 1); > + if (cg) /* verifier only check */ > + bpf_cgroup_release(cg); > + > kptr = bpf_kptr_xchg(&v->cgrp, NULL); > if (!kptr) { > err = 3; > -- > 2.30.2 >