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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 E4C28CA9ED1 for ; Fri, 1 Nov 2019 23:19:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BBDD021855 for ; Fri, 1 Nov 2019 23:19:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727549AbfKAXTB (ORCPT ); Fri, 1 Nov 2019 19:19:01 -0400 Received: from www62.your-server.de ([213.133.104.62]:50472 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725989AbfKAXTB (ORCPT ); Fri, 1 Nov 2019 19:19:01 -0400 Received: from 38.249.197.178.dynamic.dsl-lte-bonding.lssmb00p-msn.res.cust.swisscom.ch ([178.197.249.38] helo=localhost) by www62.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1iQgC1-0000T7-E6; Sat, 02 Nov 2019 00:18:57 +0100 From: Daniel Borkmann To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, ast@kernel.org, andrii.nakryiko@gmail.com, john.fastabend@gmail.com, Daniel Borkmann , Andrii Nakryiko Subject: [PATCH bpf-next v3 5/8] bpf: Switch BPF probe insns to bpf_probe_read_kernel Date: Sat, 2 Nov 2019 00:18:00 +0100 Message-Id: X-Mailer: git-send-email 2.21.0 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.101.4/25620/Fri Nov 1 10:04:15 2019) Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Commit 2a02759ef5f8 ("bpf: Add support for BTF pointers to interpreter") explicitly states that the pointer to BTF object is a pointer to a kernel object or NULL. Therefore we should also switch to using the strict kernel probe helper which is restricted to kernel addresses only when architectures have non-overlapping address spaces. Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko --- kernel/bpf/core.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 673f5d40a93e..76452326fd8e 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1309,11 +1309,12 @@ bool bpf_opcode_in_insntable(u8 code) } #ifndef CONFIG_BPF_JIT_ALWAYS_ON -u64 __weak bpf_probe_read(void * dst, u32 size, const void * unsafe_ptr) +u64 __weak bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr) { memset(dst, 0, size); return -EFAULT; } + /** * __bpf_prog_run - run eBPF program on a given context * @regs: is the array of MAX_BPF_EXT_REG eBPF pseudo-registers @@ -1569,9 +1570,9 @@ static u64 __no_fgcse ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u6 LDST(W, u32) LDST(DW, u64) #undef LDST -#define LDX_PROBE(SIZEOP, SIZE) \ - LDX_PROBE_MEM_##SIZEOP: \ - bpf_probe_read(&DST, SIZE, (const void *)(long) SRC); \ +#define LDX_PROBE(SIZEOP, SIZE) \ + LDX_PROBE_MEM_##SIZEOP: \ + bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) SRC); \ CONT; LDX_PROBE(B, 1) LDX_PROBE(H, 2) -- 2.21.0