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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 2EBA6C433DF for ; Mon, 17 Aug 2020 17:49:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03049207DF for ; Mon, 17 Aug 2020 17:49:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597686579; bh=JmPjiIGxttXu3Rqp7YXhR5qsOFbfyP+St63b9kRYUfQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YsJ81PrA25LSWTG27KDPj8+WxdUfJb5P0CNkDM7thTjpcNhPn8cPLwjbi5sA6wJ7l ss6FnJpfuKEDCh1Y3g46rNd6YBaE2NtPpaBOmWCj5r0mtACWAAjzwa/6i7SFYLarOb 4PHFCbkf7nLGhBLITwAL+zXC4ZuuPujv0vmoagA4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389917AbgHQRtg (ORCPT ); Mon, 17 Aug 2020 13:49:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:45660 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388726AbgHQQMw (ORCPT ); Mon, 17 Aug 2020 12:12:52 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 39CB6207DE; Mon, 17 Aug 2020 16:12:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597680771; bh=JmPjiIGxttXu3Rqp7YXhR5qsOFbfyP+St63b9kRYUfQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X5RjeRtrylxLSeTR9kJjKBBhU1h2fg8afeLKUXzKojlLP1cHI+HQHtNjlOdJedyPj 2pgnBGxb+vD1s1+D1BPlIT3+usu+5arX2AwHNyl8Cd2CnVy1uQUAX7ZN/+l67WKlP1 idLFvgayQ42aNtmhYsgAfH1d7G12JEBCfmPBxeXQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, jbaron@akamai.com, Jim Cromie , Sasha Levin Subject: [PATCH 4.19 051/168] dyndbg: fix a BUG_ON in ddebug_describe_flags Date: Mon, 17 Aug 2020 17:16:22 +0200 Message-Id: <20200817143736.291298404@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817143733.692105228@linuxfoundation.org> References: <20200817143733.692105228@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Jim Cromie [ Upstream commit f678ce8cc3cb2ad29df75d8824c74f36398ba871 ] ddebug_describe_flags() currently fills a caller provided string buffer, after testing its size (also passed) in a BUG_ON. Fix this by replacing them with a known-big-enough string buffer wrapped in a struct, and passing that instead. Also simplify ddebug_describe_flags() flags parameter from a struct to a member in that struct, and hoist the member deref up to the caller. This makes the function reusable (soon) where flags are unpacked. Acked-by: Signed-off-by: Jim Cromie Link: https://lore.kernel.org/r/20200719231058.1586423-8-jim.cromie@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- lib/dynamic_debug.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index dbf2b457e47e6..9305ff43fc155 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -85,22 +85,22 @@ static struct { unsigned flag:8; char opt_char; } opt_array[] = { { _DPRINTK_FLAGS_NONE, '_' }, }; +struct flagsbuf { char buf[ARRAY_SIZE(opt_array)+1]; }; + /* format a string into buf[] which describes the _ddebug's flags */ -static char *ddebug_describe_flags(struct _ddebug *dp, char *buf, - size_t maxlen) +static char *ddebug_describe_flags(unsigned int flags, struct flagsbuf *fb) { - char *p = buf; + char *p = fb->buf; int i; - BUG_ON(maxlen < 6); for (i = 0; i < ARRAY_SIZE(opt_array); ++i) - if (dp->flags & opt_array[i].flag) + if (flags & opt_array[i].flag) *p++ = opt_array[i].opt_char; - if (p == buf) + if (p == fb->buf) *p++ = '_'; *p = '\0'; - return buf; + return fb->buf; } #define vpr_info(fmt, ...) \ @@ -142,7 +142,7 @@ static int ddebug_change(const struct ddebug_query *query, struct ddebug_table *dt; unsigned int newflags; unsigned int nfound = 0; - char flagbuf[10]; + struct flagsbuf fbuf; /* search for matching ddebugs */ mutex_lock(&ddebug_lock); @@ -199,8 +199,7 @@ static int ddebug_change(const struct ddebug_query *query, vpr_info("changed %s:%d [%s]%s =%s\n", trim_prefix(dp->filename), dp->lineno, dt->mod_name, dp->function, - ddebug_describe_flags(dp, flagbuf, - sizeof(flagbuf))); + ddebug_describe_flags(dp->flags, &fbuf)); } } mutex_unlock(&ddebug_lock); @@ -779,7 +778,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p) { struct ddebug_iter *iter = m->private; struct _ddebug *dp = p; - char flagsbuf[10]; + struct flagsbuf flags; vpr_info("called m=%p p=%p\n", m, p); @@ -792,7 +791,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p) seq_printf(m, "%s:%u [%s]%s =%s \"", trim_prefix(dp->filename), dp->lineno, iter->table->mod_name, dp->function, - ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf))); + ddebug_describe_flags(dp->flags, &flags)); seq_escape(m, dp->format, "\t\r\n\""); seq_puts(m, "\"\n"); -- 2.25.1