From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: Re: [PATCH bpf-next 0/3] bpf: cleanups on managing subprog information Date: Wed, 2 May 2018 10:24:08 -0700 Message-ID: References: <1525127296-3573-1-git-send-email-jiong.wang@netronome.com> <20180501222257.cogbkcsncrmg54p5@ast-mbp> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: borkmann@iogearbox.net, ecree@solarflare.com, netdev@vger.kernel.org, oss-drivers@netronome.com To: Jiong Wang , Alexei Starovoitov Return-path: Received: from mail-it0-f65.google.com ([209.85.214.65]:54542 "EHLO mail-it0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750970AbeEBRYY (ORCPT ); Wed, 2 May 2018 13:24:24 -0400 Received: by mail-it0-f65.google.com with SMTP id z6-v6so14563084iti.4 for ; Wed, 02 May 2018 10:24:24 -0700 (PDT) In-Reply-To: Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 05/02/2018 09:59 AM, Jiong Wang wrote: > On 01/05/2018 23:22, Alexei Starovoitov wrote: > ... >> [   27.784931]  ? bpf_int_jit_compile+0x7ac/0xab0 >> [   27.785475]  bpf_int_jit_compile+0x2b6/0xab0 >> [   27.786001]  ? do_jit+0x6020/0x6020 >> [   27.786428]  ? kasan_kmalloc+0xa0/0xd0 >> [   27.786885]  bpf_check+0x2c05/0x4c40 >> [   27.787346]  ? fixup_bpf_calls+0x1140/0x1140 >> [   27.787865]  ? kasan_unpoison_shadow+0x30/0x40 >> [   27.788406]  ? kasan_kmalloc+0xa0/0xd0 >> [   27.788865]  ? memset+0x1f/0x40 >> [   27.789255]  ? bpf_obj_name_cpy+0x2d/0x200 >> [   27.789750]  bpf_prog_load+0xb07/0xeb0 >> >> simply running test_verifier with JIT and kasan on. > > Ah, sorry, I should add "sysctl net/core/bpf_jit_enable=1" to my test > script, error reproduced. > > convert_ctx_accesses and fixup_bpf_calls might insert ebpf insns that > prog->len would change. > > The new fake "exit" subprog whose .start offset is prog->len should be > updated as well. > > The "for" condition in adjust_subprog_starts: > >   for (i = 0; i < env->subprog_cnt; i++) { > > need to be changed into: > >   for (i = 0; i <= env->subprog_cnt; i++) { > > Will respin the patch set. > > Thanks. > > Regards, > Jiong > Also a bit of a nit, but if you are doing a respin. How about consider renaming BPF_MAX_SUBPROGS -> BPF_MAX_PROGS. It will make the naming more accurate and also avoid some diffs below where changing '>=' to '>' is required. @@ -191,7 +191,7 @@ struct bpf_verifier_env { bool seen_direct_write; struct bpf_insn_aux_data *insn_aux_data; /* array of per-insn state */ struct bpf_verifier_log log; - u32 subprog_starts[BPF_MAX_SUBPROGS]; + u32 subprog_starts[BPF_MAX_SUBPROGS + 1]; /* computes the stack depth of each bpf function */ u16 subprog_stack_depth[BPF_MAX_SUBPROGS + 1]; u32 subprog_cnt;