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=-10.5 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 79B71C43441 for ; Thu, 29 Nov 2018 14:13:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 42B9C208E7 for ; Thu, 29 Nov 2018 14:13:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="mdxKRWY2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 42B9C208E7 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 S1728728AbeK3BTV (ORCPT ); Thu, 29 Nov 2018 20:19:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:39826 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726989AbeK3BTU (ORCPT ); Thu, 29 Nov 2018 20:19:20 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (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 E2DE4205C9; Thu, 29 Nov 2018 14:13:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543500830; bh=gB2IJmUD3EDJH9TWZEUtn4MZ0KwVGUbMyum6dQYGxEk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mdxKRWY2iQ8ChRUq7EheQh5AffuDsI/Sl1Sv5qROfxF6EGxootq+xpCNLIsGJ91Zi bvR2r668j2z8dqorWKnSZ7lEu6lZp48kzifu8zuv9+gWfcqvYfAlJOAR3xYLfntru9 xGPjsRWEl0uF8WR7SIUy4aoPt/ax4cQ5pG+rgQiE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Prarit Bhargava , Jonathan Toppins , Jason Wessel , Daniel Thompson , kgdb-bugreport@lists.sourceforge.net, Sasha Levin Subject: [PATCH 3.18 16/83] kdb: Use strscpy with destination buffer size Date: Thu, 29 Nov 2018 15:11:34 +0100 Message-Id: <20181129140139.008141799@linuxfoundation.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181129140138.002176596@linuxfoundation.org> References: <20181129140138.002176596@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 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit c2b94c72d93d0929f48157eef128c4f9d2e603ce ] gcc 8.1.0 warns with: kernel/debug/kdb/kdb_support.c: In function ‘kallsyms_symbol_next’: kernel/debug/kdb/kdb_support.c:239:4: warning: ‘strncpy’ specified bound depends on the length of the source argument [-Wstringop-overflow=] strncpy(prefix_name, name, strlen(name)+1); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/debug/kdb/kdb_support.c:239:31: note: length computed here Use strscpy() with the destination buffer size, and use ellipses when displaying truncated symbols. v2: Use strscpy() Signed-off-by: Prarit Bhargava Cc: Jonathan Toppins Cc: Jason Wessel Cc: Daniel Thompson Cc: kgdb-bugreport@lists.sourceforge.net Reviewed-by: Daniel Thompson Signed-off-by: Daniel Thompson Signed-off-by: Sasha Levin --- kernel/debug/kdb/kdb_io.c | 15 +++++++++------ kernel/debug/kdb/kdb_private.h | 2 +- kernel/debug/kdb/kdb_support.c | 10 +++++----- 3 files changed, 15 insertions(+), 12 deletions(-) diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index 681c8b42e013..1c6b7055f11f 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -215,7 +215,7 @@ static char *kdb_read(char *buffer, size_t bufsize) int count; int i; int diag, dtab_count; - int key; + int key, buf_size, ret; diag = kdbgetintenv("DTABCOUNT", &dtab_count); @@ -335,9 +335,8 @@ poll_again: else p_tmp = tmpbuffer; len = strlen(p_tmp); - count = kallsyms_symbol_complete(p_tmp, - sizeof(tmpbuffer) - - (p_tmp - tmpbuffer)); + buf_size = sizeof(tmpbuffer) - (p_tmp - tmpbuffer); + count = kallsyms_symbol_complete(p_tmp, buf_size); if (tab == 2 && count > 0) { kdb_printf("\n%d symbols are found.", count); if (count > dtab_count) { @@ -349,9 +348,13 @@ poll_again: } kdb_printf("\n"); for (i = 0; i < count; i++) { - if (WARN_ON(!kallsyms_symbol_next(p_tmp, i))) + ret = kallsyms_symbol_next(p_tmp, i, buf_size); + if (WARN_ON(!ret)) break; - kdb_printf("%s ", p_tmp); + if (ret != -E2BIG) + kdb_printf("%s ", p_tmp); + else + kdb_printf("%s... ", p_tmp); *(p_tmp + len) = '\0'; } if (i >= dtab_count) diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h index 7afd3c8c41d5..439f1c8b1193 100644 --- a/kernel/debug/kdb/kdb_private.h +++ b/kernel/debug/kdb/kdb_private.h @@ -83,7 +83,7 @@ typedef struct __ksymtab { unsigned long sym_start; unsigned long sym_end; } kdb_symtab_t; -extern int kallsyms_symbol_next(char *prefix_name, int flag); +extern int kallsyms_symbol_next(char *prefix_name, int flag, int buf_size); extern int kallsyms_symbol_complete(char *prefix_name, int max_len); /* Exported Symbols for kernel loadable modules to use. */ diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c index d35cc2d3a4cc..2aed4a33521b 100644 --- a/kernel/debug/kdb/kdb_support.c +++ b/kernel/debug/kdb/kdb_support.c @@ -221,11 +221,13 @@ int kallsyms_symbol_complete(char *prefix_name, int max_len) * Parameters: * prefix_name prefix of a symbol name to lookup * flag 0 means search from the head, 1 means continue search. + * buf_size maximum length that can be written to prefix_name + * buffer * Returns: * 1 if a symbol matches the given prefix. * 0 if no string found */ -int kallsyms_symbol_next(char *prefix_name, int flag) +int kallsyms_symbol_next(char *prefix_name, int flag, int buf_size) { int prefix_len = strlen(prefix_name); static loff_t pos; @@ -235,10 +237,8 @@ int kallsyms_symbol_next(char *prefix_name, int flag) pos = 0; while ((name = kdb_walk_kallsyms(&pos))) { - if (strncmp(name, prefix_name, prefix_len) == 0) { - strncpy(prefix_name, name, strlen(name)+1); - return 1; - } + if (!strncmp(name, prefix_name, prefix_len)) + return strscpy(prefix_name, name, buf_size); } return 0; } -- 2.17.1