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 X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B7D93ECDE47 for ; Thu, 8 Nov 2018 22:08:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7FE41214DE for ; Thu, 8 Nov 2018 22:08:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="QAK3YB9P" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7FE41214DE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732660AbeKIHqH (ORCPT ); Fri, 9 Nov 2018 02:46:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:39718 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731402AbeKIHqG (ORCPT ); Fri, 9 Nov 2018 02:46:06 -0500 Received: from localhost (unknown [208.72.13.198]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0BF36208A3; Thu, 8 Nov 2018 22:08:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541714914; bh=xcjZHGFGgrl9V8BbYdsoyaqSiLprZFgrWKj8/+Abw70=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QAK3YB9PGJh74IBcG6o47OFtfMqxfd1KeTuQO6PLzyqaJqe67jjCOBmtG4dKzk91l 4N5PWZYcQSe68LlCfcsAqJYdV2aPOMIvfWuKRdUCsis+Tjc0F9bscWGPIQQv/yYcOi CvlepoubLrgok2dksWtu3bMWWLFrrAE7/1uyljaY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Borkmann , Edward Cree , Alexei Starovoitov , Sasha Levin Subject: [PATCH 4.14 05/31] bpf: fix partial copy of map_ptr when dst is scalar Date: Thu, 8 Nov 2018 13:52:29 -0800 Message-Id: <20181108215130.120252336@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181108215129.641434673@linuxfoundation.org> References: <20181108215129.641434673@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ commit 0962590e553331db2cc0aef2dc35c57f6300dbbe upstream. ALU operations on pointers such as scalar_reg += map_value_ptr are handled in adjust_ptr_min_max_vals(). Problem is however that map_ptr and range in the register state share a union, so transferring state through dst_reg->range = ptr_reg->range is just buggy as any new map_ptr in the dst_reg is then truncated (or null) for subsequent checks. Fix this by adding a raw member and use it for copying state over to dst_reg. Fixes: f1174f77b50c ("bpf/verifier: rework value tracking") Signed-off-by: Daniel Borkmann Cc: Edward Cree Acked-by: Alexei Starovoitov Signed-off-by: Alexei Starovoitov Acked-by: Edward Cree Signed-off-by: Sasha Levin --- include/linux/bpf_verifier.h | 3 +++ kernel/bpf/verifier.c | 10 ++++++---- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 73bec75b74c8..a3333004fd2b 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -50,6 +50,9 @@ struct bpf_reg_state { * PTR_TO_MAP_VALUE_OR_NULL */ struct bpf_map *map_ptr; + + /* Max size from any of the above. */ + unsigned long raw; }; /* Fixed part of pointer offset, pointer types only */ s32 off; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index a0ffc62e7677..013b0cd1958e 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1935,7 +1935,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, dst_reg->umax_value = umax_ptr; dst_reg->var_off = ptr_reg->var_off; dst_reg->off = ptr_reg->off + smin_val; - dst_reg->range = ptr_reg->range; + dst_reg->raw = ptr_reg->raw; break; } /* A new variable offset is created. Note that off_reg->off @@ -1965,10 +1965,11 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, } dst_reg->var_off = tnum_add(ptr_reg->var_off, off_reg->var_off); dst_reg->off = ptr_reg->off; + dst_reg->raw = ptr_reg->raw; if (ptr_reg->type == PTR_TO_PACKET) { dst_reg->id = ++env->id_gen; /* something was added to pkt_ptr, set range to zero */ - dst_reg->range = 0; + dst_reg->raw = 0; } break; case BPF_SUB: @@ -1999,7 +2000,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, dst_reg->var_off = ptr_reg->var_off; dst_reg->id = ptr_reg->id; dst_reg->off = ptr_reg->off - smin_val; - dst_reg->range = ptr_reg->range; + dst_reg->raw = ptr_reg->raw; break; } /* A new variable offset is created. If the subtrahend is known @@ -2025,11 +2026,12 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, } dst_reg->var_off = tnum_sub(ptr_reg->var_off, off_reg->var_off); dst_reg->off = ptr_reg->off; + dst_reg->raw = ptr_reg->raw; if (ptr_reg->type == PTR_TO_PACKET) { dst_reg->id = ++env->id_gen; /* something was added to pkt_ptr, set range to zero */ if (smin_val < 0) - dst_reg->range = 0; + dst_reg->raw = 0; } break; case BPF_AND: -- 2.17.1