From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754920AbcH0CcP (ORCPT ); Fri, 26 Aug 2016 22:32:15 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:6557 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754731AbcH0Cbk (ORCPT ); Fri, 26 Aug 2016 22:31:40 -0400 From: Alexei Starovoitov To: "David S . Miller" CC: Peter Zijlstra , Brendan Gregg , Daniel Borkmann , Arnaldo Carvalho de Melo , Wang Nan , , , Subject: [PATCH net-next 1/6] bpf: support 8-byte metafield access Date: Fri, 26 Aug 2016 19:31:19 -0700 Message-ID: <1472265084-1767670-2-git-send-email-ast@fb.com> X-Mailer: git-send-email 2.8.0 In-Reply-To: <1472265084-1767670-1-git-send-email-ast@fb.com> References: <1472265084-1767670-1-git-send-email-ast@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-08-26_15:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The verifier supported only 4-byte metafields in struct __sk_buff and struct xdp_md. The metafields in upcoming struct bpf_perf_event are 8-byte to match register width in struct pt_regs. Teach verifier to recognize 8-byte metafield access. The patch doesn't affect safety of sockets and xdp programs. They check for 4-byte only ctx access before these conditions are hit. Signed-off-by: Alexei Starovoitov --- kernel/bpf/verifier.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index abb61f3f6900..c1c9e441f0f5 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2333,7 +2333,8 @@ static int do_check(struct verifier_env *env) if (err) return err; - if (BPF_SIZE(insn->code) != BPF_W) { + if (BPF_SIZE(insn->code) != BPF_W && + BPF_SIZE(insn->code) != BPF_DW) { insn_idx++; continue; } @@ -2642,9 +2643,11 @@ static int convert_ctx_accesses(struct verifier_env *env) for (i = 0; i < insn_cnt; i++, insn++) { u32 insn_delta, cnt; - if (insn->code == (BPF_LDX | BPF_MEM | BPF_W)) + if (insn->code == (BPF_LDX | BPF_MEM | BPF_W) || + insn->code == (BPF_LDX | BPF_MEM | BPF_DW)) type = BPF_READ; - else if (insn->code == (BPF_STX | BPF_MEM | BPF_W)) + else if (insn->code == (BPF_STX | BPF_MEM | BPF_W) || + insn->code == (BPF_STX | BPF_MEM | BPF_DW)) type = BPF_WRITE; else continue; -- 2.8.0