From patchwork Wed May 9 21:06:59 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joe Stringer X-Patchwork-Id: 911195 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=wand.net.nz Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="TUA3B1Pv"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 40h88X2ZWNz9s1w for ; Thu, 10 May 2018 07:08:12 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965555AbeEIVH0 (ORCPT ); Wed, 9 May 2018 17:07:26 -0400 Received: from mail-ot0-f194.google.com ([74.125.82.194]:37565 "EHLO mail-ot0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964953AbeEIVHY (ORCPT ); Wed, 9 May 2018 17:07:24 -0400 Received: by mail-ot0-f194.google.com with SMTP id 77-v6so41782812otd.4 for ; Wed, 09 May 2018 14:07:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=+bCNVEXC/+fhbf9k3o1598v6fdMmMZVJhI4id1VM/T8=; b=TUA3B1Pvuc+3HRNvYFYJo/xyhyrgu4+YUa8TcUx9WFctCKBdmUXb/TTneOmU0DZKxt ylV4GS6KzkIXRz07ohzNCMHWn6UufFyWL4j1wrJ0xsVEjdYOnwEh+I3epZxxhAtAPZPZ wnRjFNQ1iBS8Rmtp/N0b8cBCRSTQBqfM1cbfJbMKw6DzEf+9vFrnfsq6WDO2DgfDF3rw h3wOFkFxfB2N8AVCBADe8Fcm2sSg6pRfLwIIQbF0B22FTs3cWjHREmjAxdcgP4iDFII5 LYEHTHoS7YCaUmDNbuIECKWOTXfxVWEhYJlhSGIi4sORpw6Ug1ytOovXAp7vD5ISEePu DXLA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references; bh=+bCNVEXC/+fhbf9k3o1598v6fdMmMZVJhI4id1VM/T8=; b=FgvwgrOKDmbqD/En6pTes7mNOmlMBTlrDsFgPYowXB9jmuxU5XR6+i03DeOUGinuxy XK9LL7pRKB99X/nqqSh8aO0l8ZEdC0UNa6u942Pd79w2feLciA2yXlFjrsxybcVyziAC B9rhmnr3OjTfKkYBTeKmei4pupSNUiCLEdsiq9BsZ1TYF242jsIODEMyo0odQQ/vj1sE 5AibeWcqc6YAv4V109HWKUFv95wLSAZh3bgNPMxzi1UAMOhZrZCYfpPgy2HxVmKIoImu Yn/lm4SmIcvH0eXz6eNToyBEfjOKrCeZBrQptivmG3zIVD+OX8CCcCr1FNVHJDfI0Ac7 5BtQ== X-Gm-Message-State: ALQs6tDYlhQpullO6K9QQj8L2wBTfWRQt8XRur6310Ii3gIprVDQA+mv 9PZesCttYkx4F9WRgpjo6QY= X-Google-Smtp-Source: AB8JxZoeiFex+NSzTx2AQ1KjJniwormlIhHlgEVUeF8qfZS1QYuThBzAOks7qiSWZOz+WIp/LF+BWA== X-Received: by 2002:a9d:1db3:: with SMTP id y48-v6mr34899664otd.8.1525900043805; Wed, 09 May 2018 14:07:23 -0700 (PDT) Received: from allosaurus.lan ([99.0.85.34]) by smtp.gmail.com with ESMTPSA id h125-v6sm13612921oic.54.2018.05.09.14.07.22 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 May 2018 14:07:23 -0700 (PDT) From: Joe Stringer To: daniel@iogearbox.net Cc: netdev@vger.kernel.org, ast@kernel.org, john.fastabend@gmail.com, kafai@fb.com Subject: [RFC bpf-next 01/11] bpf: Add iterator for spilled registers Date: Wed, 9 May 2018 14:06:59 -0700 Message-Id: <20180509210709.7201-2-joe@wand.net.nz> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20180509210709.7201-1-joe@wand.net.nz> References: <20180509210709.7201-1-joe@wand.net.nz> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Add this iterator for spilled registers, it concentrates the details of how to get the current frame's spilled registers into a single macro while clarifying the intention of the code which is calling the macro. Signed-off-by: Joe Stringer --- include/linux/bpf_verifier.h | 11 +++++++++++ kernel/bpf/verifier.c | 16 +++++++--------- 2 files changed, 18 insertions(+), 9 deletions(-) diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 8f70dc181e23..a613b52ce939 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -133,6 +133,17 @@ struct bpf_verifier_state { u32 curframe; }; +#define __get_spilled_reg(slot, frame) \ + (((slot < frame->allocated_stack / BPF_REG_SIZE) && \ + (frame->stack[slot].slot_type[0] == STACK_SPILL)) \ + ? &frame->stack[slot].spilled_ptr : NULL) + +/* Iterate over 'frame', setting 'reg' to either NULL or a spilled register. */ +#define for_each_spilled_reg(iter, frame, reg) \ + for (iter = 0, reg = __get_spilled_reg(iter, frame); \ + iter < frame->allocated_stack / BPF_REG_SIZE; \ + iter++, reg = __get_spilled_reg(iter, frame)) + /* linked list of verifier states used to prune search */ struct bpf_verifier_state_list { struct bpf_verifier_state state; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index d92d9c37affd..f40e089c3893 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2216,10 +2216,9 @@ static void __clear_all_pkt_pointers(struct bpf_verifier_env *env, if (reg_is_pkt_pointer_any(®s[i])) mark_reg_unknown(env, regs, i); - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] != STACK_SPILL) + for_each_spilled_reg(i, state, reg) { + if (!reg) continue; - reg = &state->stack[i].spilled_ptr; if (reg_is_pkt_pointer_any(reg)) __mark_reg_unknown(reg); } @@ -3326,10 +3325,9 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *vstate, for (j = 0; j <= vstate->curframe; j++) { state = vstate->frame[j]; - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] != STACK_SPILL) + for_each_spilled_reg(i, state, reg) { + if (!reg) continue; - reg = &state->stack[i].spilled_ptr; if (reg->type == type && reg->id == dst_reg->id) reg->range = max(reg->range, new_range); } @@ -3574,7 +3572,7 @@ static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno, bool is_null) { struct bpf_func_state *state = vstate->frame[vstate->curframe]; - struct bpf_reg_state *regs = state->regs; + struct bpf_reg_state *reg, *regs = state->regs; u32 id = regs[regno].id; int i, j; @@ -3583,8 +3581,8 @@ static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno, for (j = 0; j <= vstate->curframe; j++) { state = vstate->frame[j]; - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] != STACK_SPILL) + for_each_spilled_reg(i, state, reg) { + if (!reg) continue; mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null); }