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 4A9B2C433FE for ; Mon, 7 Nov 2022 13:17:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231286AbiKGNRW (ORCPT ); Mon, 7 Nov 2022 08:17:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53322 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231551AbiKGNRU (ORCPT ); Mon, 7 Nov 2022 08:17:20 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 617A6615C for ; Mon, 7 Nov 2022 05:17:16 -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 11238B80DF2 for ; Mon, 7 Nov 2022 13:17:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EEB42C433C1; Mon, 7 Nov 2022 13:17:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667827033; bh=tisMPvmQNILTB7LyB3EX0agbELSzq8kO29YbQ9xN0Jc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=IJDf4vhRTqNwvRn2xO+C0oA6M2BJBQNtVfvf34X/iDAxnbWeNBCX0ZZI6WOk7HTJM oSzU0vbvpXb3aHMcbakCvYJNpisj8K3rkrjROnKwDALVQcIuUvXHpjKxCJTh+S7OE5 xKtgWA9pFz2SuSD7zxM7aw1S3WwoCziLxBjhmSyjasxVDkv4oDyvJBzSeSe5x73RJZ b62JZJCxFgfhsmA1sHhHqFcWGtbUZ8n6SBAQANN0n7G7nzV47aPMDPXxuyPJrah9NR fvWPDHnvICMvk2Smd49/Hx9bsOLIjhvNPj8c/hJ7gCzWv/6fWu/Fr18Q4vIXZ1EXBn 5mIcSkcQcHWlw== Date: Mon, 7 Nov 2022 22:17:10 +0900 From: Masami Hiramatsu (Google) To: wangyufen Cc: , , Subject: Re: [PATCH v2] tracing: fix memory leak in tracing_read_pipe Message-Id: <20221107221710.23d90a4cf74043a9b5f7d6fc@kernel.org> In-Reply-To: References: <1667819090-4643-1-git-send-email-wangyufen@huawei.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 7 Nov 2022 19:45:04 +0800 wangyufen wrote: > > 在 2022/11/7 19:04, Wang Yufen 写道: > > kmemleak reports this issue: > > > > unreferenced object 0xffff888105a18900 (size 128): > > comm "test_progs", pid 18933, jiffies 4336275356 (age 22801.766s) > > hex dump (first 32 bytes): > > 25 73 00 90 81 88 ff ff 26 05 00 00 42 01 58 04 %s......&...B.X. > > 03 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 ................ > > backtrace: > > [<00000000560143a1>] __kmalloc_node_track_caller+0x4a/0x140 > > [<000000006af00822>] krealloc+0x8d/0xf0 > > [<00000000c309be6a>] trace_iter_expand_format+0x99/0x150 > > [<000000005a53bdb6>] trace_check_vprintf+0x1e0/0x11d0 > > [<0000000065629d9d>] trace_event_printf+0xb6/0xf0 > > [<000000009a690dc7>] trace_raw_output_bpf_trace_printk+0x89/0xc0 > > [<00000000d22db172>] print_trace_line+0x73c/0x1480 > > [<00000000cdba76ba>] tracing_read_pipe+0x45c/0x9f0 > > [<0000000015b58459>] vfs_read+0x17b/0x7c0 > > [<000000004aeee8ed>] ksys_read+0xed/0x1c0 > > [<0000000063d3d898>] do_syscall_64+0x3b/0x90 > > [<00000000a06dda7f>] entry_SYSCALL_64_after_hwframe+0x63/0xcd > > > > iter->fmt alloced in > > tracing_read_pipe() -> .. ->trace_iter_expand_format(), but not > > freed, to fix, add free in tracing_release_pipe() > Fixes: efbbdaa22bb7 ("tracing: Show real address for trace event arguments") Oops, good catch! Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu (Google) Thank you, > > Signed-off-by: Wang Yufen > > --- > > v1 -> v2: del if (iter->fmt), free iter->fmt directly > > kernel/trace/trace.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > > index 47a44b0..f9d98e7 100644 > > --- a/kernel/trace/trace.c > > +++ b/kernel/trace/trace.c > > @@ -6657,6 +6657,7 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) > > mutex_unlock(&trace_types_lock); > > > > free_cpumask_var(iter->started); > > + kfree(iter->fmt); > > mutex_destroy(&iter->mutex); > > kfree(iter); > > -- Masami Hiramatsu (Google)