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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,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 601D5C433DF for ; Mon, 10 Aug 2020 19:14:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 39A6A207FF for ; Mon, 10 Aug 2020 19:14:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597086861; bh=bKZyCJY5tcwU9+t7Ri2QDzZnhI/88fXqAczSnav0mCs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CcPbx80jr5Wpl6G9Av9ESMLbjVTOkdhPTn6cNttA9FRlTtp/5dq0p5P8bpfmxLCkV 9nhzKB04e5aE3KAsV7hCz8mWoJlXpLIqlBvXgen/fo160SQ/RUPl/h8Hmhx1O2X4Nd TUgi9zIKI7thYtjSfX1fT0y5ZFyJoWR26cYvC0uA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729991AbgHJTOU (ORCPT ); Mon, 10 Aug 2020 15:14:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:46110 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729967AbgHJTON (ORCPT ); Mon, 10 Aug 2020 15:14:13 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B6AA322BEB; Mon, 10 Aug 2020 19:14:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597086852; bh=bKZyCJY5tcwU9+t7Ri2QDzZnhI/88fXqAczSnav0mCs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=in/KT4qGDEnADJhB8o3L4zD2Cq/qiWE8kHqJe7AJ15AKb7iqQf++nm5mOYG+g//EW 04AXbJXLwZFl8FbMdLQMHfzC1kYJbj42AlABr5Dn0WnflocuiLcmvj+73t4B8B8zvv bUciHEXcb+l8i8B6UiZ3DLlbDaG2eJ8B3z4+lsxk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jim Cromie , jbaron@akamai.com, Greg Kroah-Hartman , Sasha Levin Subject: [PATCH AUTOSEL 4.14 19/22] dyndbg: fix a BUG_ON in ddebug_describe_flags Date: Mon, 10 Aug 2020 15:13:41 -0400 Message-Id: <20200810191345.3795166-19-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200810191345.3795166-1-sashal@kernel.org> References: <20200810191345.3795166-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 c7c96bc7654af..91c451e0f4741 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