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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 B9171C433DF for ; Tue, 9 Jun 2020 04:34:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7863D20814 for ; Tue, 9 Jun 2020 04:34:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="qRNNgiKy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7863D20814 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 215118D001B; Tue, 9 Jun 2020 00:34:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1C5B58D0011; Tue, 9 Jun 2020 00:34:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 102208D001B; Tue, 9 Jun 2020 00:34:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0095.hostedemail.com [216.40.44.95]) by kanga.kvack.org (Postfix) with ESMTP id EB7618D0011 for ; Tue, 9 Jun 2020 00:34:32 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id B0F91181ABEA4 for ; Tue, 9 Jun 2020 04:34:32 +0000 (UTC) X-FDA: 76908407184.03.value15_4a15b2c26dbf Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin03.hostedemail.com (Postfix) with ESMTP id 852D73F016 for ; Tue, 9 Jun 2020 04:34:32 +0000 (UTC) X-HE-Tag: value15_4a15b2c26dbf X-Filterd-Recvd-Size: 3673 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf36.hostedemail.com (Postfix) with ESMTP for ; Tue, 9 Jun 2020 04:34:32 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 1F83020842; Tue, 9 Jun 2020 04:34:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591677271; bh=bJYVAO7ZXtOlXBvZv3hJqo4z1fY0sd7UdmUS0Iu1G1s=; h=Date:From:To:Subject:In-Reply-To:From; b=qRNNgiKyYhjvoiTGhkaXwOsmxqbtTCmLTk+msXFitqaKUsr9q8wGQnhdIRNIX1WLf 6YBR1BjNxOPEKOi/u+8uNW8o7QJmd7PCjd8qIOSE9GSQoPxN+n2OHxpI4sZOJo8HwW 3Sb32rCa+fkdMfm2tc6iT7jLfrg1pZtJZFakoHTM= Date: Mon, 08 Jun 2020 21:34:30 -0700 From: Andrew Morton To: akpm@linux-foundation.org, ast@kernel.org, daniel@iogearbox.net, hch@lst.de, hpa@zytor.com, linux-mm@kvack.org, mhiramat@kernel.org, mingo@elte.hu, mm-commits@vger.kernel.org, tglx@linutronix.de, torvalds@linux-foundation.org Subject: [patch 82/93] bpf: factor out a bpf_trace_copy_string helper Message-ID: <20200609043430.w6Gil863r%akpm@linux-foundation.org> In-Reply-To: <20200608212922.5b7fa74ca3f4e2444441b7f9@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: 852D73F016 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Christoph Hellwig Subject: bpf: factor out a bpf_trace_copy_string helper Split out a helper to do the fault free access to the string pointer to get it out of a crazy indentation level. Link: http://lkml.kernel.org/r/20200521152301.2587579-12-hch@lst.de Signed-off-by: Christoph Hellwig Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Masami Hiramatsu Cc: Thomas Gleixner Signed-off-by: Andrew Morton --- kernel/trace/bpf_trace.c | 42 +++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 18 deletions(-) --- a/kernel/trace/bpf_trace.c~bpf-factor-out-a-bpf_trace_copy_string-helper +++ a/kernel/trace/bpf_trace.c @@ -324,6 +324,28 @@ static const struct bpf_func_proto *bpf_ return &bpf_probe_write_user_proto; } +static void bpf_trace_copy_string(char *buf, void *unsafe_ptr, char fmt_ptype, + size_t bufsz) +{ + void __user *user_ptr = (__force void __user *)unsafe_ptr; + + buf[0] = 0; + + switch (fmt_ptype) { + case 's': +#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE + strncpy_from_unsafe(buf, unsafe_ptr, bufsz); + break; +#endif + case 'k': + strncpy_from_kernel_nofault(buf, unsafe_ptr, bufsz); + break; + case 'u': + strncpy_from_user_nofault(buf, user_ptr, bufsz); + break; + } +} + /* * Only limited trace_printk() conversion specifiers allowed: * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %pks %pus %s @@ -406,24 +428,8 @@ fmt_str: break; } - buf[0] = 0; - switch (fmt_ptype) { - case 's': -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE - strncpy_from_unsafe(buf, unsafe_ptr, - sizeof(buf)); - break; -#endif - case 'k': - strncpy_from_kernel_nofault(buf, unsafe_ptr, - sizeof(buf)); - break; - case 'u': - strncpy_from_user_nofault(buf, - (__force void __user *)unsafe_ptr, - sizeof(buf)); - break; - } + bpf_trace_copy_string(buf, unsafe_ptr, fmt_ptype, + sizeof(buf)); goto fmt_next; } _