From nobody Thu Apr 9 13:41:51 2026 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 5080FC4332F for ; Mon, 7 Nov 2022 10:24:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231552AbiKGKYS (ORCPT ); Mon, 7 Nov 2022 05:24:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35142 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231790AbiKGKX6 (ORCPT ); Mon, 7 Nov 2022 05:23:58 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C3426165AA for ; Mon, 7 Nov 2022 02:23:57 -0800 (PST) Received: from canpemm500010.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4N5S0d3zNrzpW9j; Mon, 7 Nov 2022 18:20:17 +0800 (CST) Received: from localhost.localdomain (10.175.112.70) by canpemm500010.china.huawei.com (7.192.105.118) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 7 Nov 2022 18:23:55 +0800 From: Wang Yufen To: CC: , , Wang Yufen Subject: [PATCH] tracing: fix memory leak in tracing_read_pipe Date: Mon, 7 Nov 2022 18:44:22 +0800 Message-ID: <1667817862-48989-1-git-send-email-wangyufen@huawei.com> X-Mailer: git-send-email 1.8.3.1 MIME-Version: 1.0 X-Originating-IP: [10.175.112.70] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To canpemm500010.china.huawei.com (7.192.105.118) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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() Signed-off-by: Wang Yufen --- kernel/trace/trace.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 47a44b0..ced81a9 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -6657,6 +6657,8 @@ static int tracing_release_pipe(struct inode *inode, = struct file *file) mutex_unlock(&trace_types_lock); =20 free_cpumask_var(iter->started); + if (iter->fmt) + kfree(iter->fmt); mutex_destroy(&iter->mutex); kfree(iter); =20 --=20 1.8.3.1