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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 37A3EC433E1 for ; Wed, 17 Jun 2020 16:26:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13C1C21532 for ; Wed, 17 Jun 2020 16:26:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="KI4pqwh+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727024AbgFQQ0T (ORCPT ); Wed, 17 Jun 2020 12:26:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48982 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726329AbgFQQ0I (ORCPT ); Wed, 17 Jun 2020 12:26:08 -0400 Received: from mail-oo1-xc43.google.com (mail-oo1-xc43.google.com [IPv6:2607:f8b0:4864:20::c43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0E60C06174E for ; Wed, 17 Jun 2020 09:26:08 -0700 (PDT) Received: by mail-oo1-xc43.google.com with SMTP id v1so529835ooh.0 for ; Wed, 17 Jun 2020 09:26:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=V4vaC8jH1uAkf0e4xv8Z3CqlZMc6lIX3fCOrUzVEUYI=; b=KI4pqwh+XCkyNnXG1j38RmHM9YUoW1IzdAMc9ZsD7Sh3MbbRYftqNC978juv0E5lfG ydZzMa0Pbiy4JOwnzQAEPbFUQaQe0kiWDb7hzZSyWYkNvGKrXZ2NnJpsPL4cHyoa046+ WYvxCWzMaNc3h6uQpesOXBseXWURfndQ7IEbwlav/HEp/MTmj8x+G01+SaDeJqBnPtNC CbYnB3woElpXnzT8LeQ4xuu2t7/KcuPmsJbZ1b53oxL0hoRxoSCcjkR6EJfHtFkyVJKO +KPA//vQFPwH4UcBTtvgUKLnOyqOz5P6Xa5eU51059I6H4yiopSc2pyK8IKO9MDGOqrL W2Ow== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=V4vaC8jH1uAkf0e4xv8Z3CqlZMc6lIX3fCOrUzVEUYI=; b=ZFyUbi0j078+IsD1FhzjboGsTu6lRpks1DLe+6T+c4u8/Clwau8wHPGDrEiU1XmYOx I0b/rTYI1fWbRLdW/NRrvBZRwyKWgmJpB0vqoiwwaFFUSoBLBt2wAx5xV+aP/Vn1gm9N ld5J+HCo48kuz8IhztF3skzH7TsXnsETfUXP+Lb3AIio1BP2x6hkacUYuDE17oUGJGof +0EFuzIbpDCR6I7gi/DKhwGiA+XCwIyCEkaTW2p7e8Me5ne4vGHThjubneN0JNXPtcDW +27ivnAyKtcLYGyL66ERWYcoAEH1fuVljQb8HvSGOt6uVWf0KHuAQ+1BpG9n1Bo2dIu0 9kuA== X-Gm-Message-State: AOAM5312dRU8jTTXTQ73THQ+QXq3vUtoy6dwLne9PWjuPnSqViHWbX/j CNUN0vmX3gPxAsTlhWyMF4MspXqLByM= X-Google-Smtp-Source: ABdhPJwulPf8PAjGI11HpznAlFwPhOoBNltmelbjqWtLXNOnVoMi600gz5AHyu3YRVLxGET91eqzsg== X-Received: by 2002:a4a:4c8e:: with SMTP id a136mr159067oob.23.1592411168149; Wed, 17 Jun 2020 09:26:08 -0700 (PDT) Received: from frodo.hsd1.co.comcast.net ([2601:284:8204:6ba0::ae4b]) by smtp.googlemail.com with ESMTPSA id h7sm95877otk.48.2020.06.17.09.26.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Jun 2020 09:26:07 -0700 (PDT) From: Jim Cromie To: jbaron@akamai.com, linux-kernel@vger.kernel.org, akpm@linuxfoundation.org, gregkh@linuxfoundation.org Cc: linux@rasmusvillemoes.dk, Jim Cromie Subject: [PATCH v3 07/21] dyndbg: fix a BUG_ON in ddebug_describe_flags Date: Wed, 17 Jun 2020 10:25:20 -0600 Message-Id: <20200617162536.611386-8-jim.cromie@gmail.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200617162536.611386-1-jim.cromie@gmail.com> References: <20200617162536.611386-1-jim.cromie@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Signed-off-by: Jim Cromie --- 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 9b2445507988..0cb5679f6c54 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -87,22 +87,22 @@ 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 vnpr_info(lvl, fmt, ...) \ @@ -147,7 +147,7 @@ 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); @@ -204,8 +204,7 @@ static int ddebug_change(const struct ddebug_query *query, v2pr_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); @@ -814,7 +813,7 @@ 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; if (p == SEQ_START_TOKEN) { seq_puts(m, @@ -825,7 +824,7 @@ 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"); -- 2.26.2