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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 798F9C64ED6 for ; Sun, 26 Feb 2023 03:46:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230105AbjBZDqO (ORCPT ); Sat, 25 Feb 2023 22:46:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230021AbjBZDp4 (ORCPT ); Sat, 25 Feb 2023 22:45:56 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B7FB17CF3; Sat, 25 Feb 2023 19:45:15 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CE680B80B90; Sun, 26 Feb 2023 03:44:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 89AA3C4339C; Sun, 26 Feb 2023 03:44:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677383045; bh=m3Bi8ykRKz7C0lnLkCzrDQ+YdKhyypTsGT7n3gsu0GM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qfJJqRQciUXpVPIXCb9b/mCnGE2UmQNxDPN/V3BR4mXzuv2xcs4ihrf3S5NiO5JQW C/16lPPBK1hzmWvFX2aUUP/Z4Gz5Uf0LAoA7K4jPKGpcEbnEwPLsZRyi3cohrcQGjG DDcEGFRDfP6uxXRvDBSO5mzmtSQYC4fJCtLbU+patf+nNXv0D8AqWOUIcrgaR+ywRm 55WbDQJ8VdQynm+hIiB/8Nlf050OIr0k/wLV68B//YAw54p+NU7donri6oykZOQSQA TJ24h8T9k7AIzB53/MzsaPXG7FgA+yoc3ilPDOqUgoDKT7q69/QZxr4DrepIn6o5rV IZGKmDdKhyC+w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Jens Axboe , Steven Rostedt , Masami Hiramatsu , linux-block@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Bart Van Assche , Sasha Levin Subject: [PATCH AUTOSEL 5.15 4/6] trace/blktrace: fix memory leak with using debugfs_lookup() Date: Sat, 25 Feb 2023 22:43:56 -0500 Message-Id: <20230226034359.773806-4-sashal@kernel.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230226034359.773806-1-sashal@kernel.org> References: <20230226034359.773806-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg Kroah-Hartman [ Upstream commit 83e8864fee26f63a7435e941b7c36a20fd6fe93e ] When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Cc: Jens Axboe Cc: Steven Rostedt Cc: Masami Hiramatsu Cc: linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-kernel@vger.kernel.org Signed-off-by: Greg Kroah-Hartman Reviewed-by: Bart Van Assche Link: https://lore.kernel.org/r/20230202141956.2299521-1-gregkh@linuxfoundation.org Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- kernel/trace/blktrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 16b0d3fa56e00..e6d03cf148597 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -319,8 +319,8 @@ static void blk_trace_free(struct request_queue *q, struct blk_trace *bt) * under 'q->debugfs_dir', thus lookup and remove them. */ if (!bt->dir) { - debugfs_remove(debugfs_lookup("dropped", q->debugfs_dir)); - debugfs_remove(debugfs_lookup("msg", q->debugfs_dir)); + debugfs_lookup_and_remove("dropped", q->debugfs_dir); + debugfs_lookup_and_remove("msg", q->debugfs_dir); } else { debugfs_remove(bt->dir); } -- 2.39.0