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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D94EC433EF for ; Sun, 10 Oct 2021 10:25:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 85B2860F22 for ; Sun, 10 Oct 2021 10:25:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231566AbhJJK1M (ORCPT ); Sun, 10 Oct 2021 06:27:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37020 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231508AbhJJK1L (ORCPT ); Sun, 10 Oct 2021 06:27:11 -0400 Received: from mail-pj1-x1031.google.com (mail-pj1-x1031.google.com [IPv6:2607:f8b0:4864:20::1031]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC1CAC061570 for ; Sun, 10 Oct 2021 03:25:12 -0700 (PDT) Received: by mail-pj1-x1031.google.com with SMTP id d13-20020a17090ad3cd00b0019e746f7bd4so12573637pjw.0 for ; Sun, 10 Oct 2021 03:25:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=kA2EwLBNslfvLXzwvv6riahnuFRUNL4Ji93TNaMdqWw=; b=kEFDgKkEq/zxSZYac6l6ZjjVgkY1czV8YOB0tYSIMB0QL2X6aHOppTpZfYB/tnSbTc JDU9Ojqv0frjBk06/Rxl7IB5gFgBBmrCldmIVd+S/v9/8ZJtANxmWFzd3Q0jKtcF0sim vFkNAnHU21icNgJhdpyS1CcSFBY+vp6BbPrNunulil3Dg57dxGzPfMd/gbYxP77UIu1p XrghXnl+/X7degOKakCtIKaXDF8oT3Ll5esaOpYnyJAzsBOPCIXJR0+oe/ZIywGqEkdf h+izI2/oJZmTfyaf+N4BqfUS31UkjuzbNeMAJ+Fj1P4R+btJTlyMMlcBRsDFdmfH74Ka 9jYw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=kA2EwLBNslfvLXzwvv6riahnuFRUNL4Ji93TNaMdqWw=; b=LvwoDIYaU3KU/PK7GSe7hBOjzRBX34Qoojkh641lFglTUyckLA5DicAzJAU441jmml m6Epw+LQboimE7JvJy83tWxdcHW+z6eVwi+Vkm/25OPVCbfdj9urry64ReNaHwJFBuTL 0dmuas4CknIDeVzvGPaZsXcPEQtg1BR57G1zt6zJVfQX+G+mF4bhEM29uptl240RI66l k0ceeJAy4PsXlboryfjpT3pM/ScNDP8ckkQQ5pzfgL91w/0C4fAnPL/tL/Euizo192Dq SpOC5DHF3jh8BL/ZE6bHIwqRv9U1DaciudaTZyolUpKMJ89S7tYyUKyimKla7xG3EGgK xFSw== X-Gm-Message-State: AOAM5321T1yQX9hA0bUoqiACtNl9GpCatiQ0I35dZuo31ULJKO473GsJ TB1bCZw+DmP2Y6K5ScAikjY= X-Google-Smtp-Source: ABdhPJwPqrMTwqJV7XGuSl4axhz3iL7t4tPpTrW/GBk0FNRrAWsL/sE65ZKOMVf/MqZ7IIMFqretvA== X-Received: by 2002:a17:90a:9317:: with SMTP id p23mr23314201pjo.151.1633861512295; Sun, 10 Oct 2021 03:25:12 -0700 (PDT) Received: from vultr.guest ([144.202.123.152]) by smtp.gmail.com with ESMTPSA id w4sm4347494pfb.3.2021.10.10.03.25.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 10 Oct 2021 03:25:11 -0700 (PDT) From: Yafang Shao To: keescook@chromium.org, rostedt@goodmis.org, peterz@infradead.org, pmladek@suse.com, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, valentin.schneider@arm.com, mathieu.desnoyers@efficios.com, qiang.zhang@windriver.com, robdclark@chromium.org, christian@brauner.io, dietmar.eggemann@arm.com, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com Cc: linux-kernel@vger.kernel.org, Yafang Shao , Vladimir Zapolskiy , David Howells Subject: [PATCH v3 1/4] connector: use __get_task_comm in proc_comm_connector Date: Sun, 10 Oct 2021 10:24:26 +0000 Message-Id: <20211010102429.99577-2-laoar.shao@gmail.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20211010102429.99577-1-laoar.shao@gmail.com> References: <20211010102429.99577-1-laoar.shao@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org connector comm was introduced in commit f786ecba4158 ("connector: add comm change event report to proc connector"). struct comm_proc_event was defined in include/linux/cn_proc.h first and then been moved into file include/uapi/linux/cn_proc.h in commit 607ca46e97a1 ("UAPI: (Scripted) Disintegrate include/linux"). As this is the UAPI code, we can't change it without potentially breaking things (i.e. userspace binaries have this size built in, so we can't just change the size). To prepare for the followup change - extending task comm, we have to use __get_task_comm() to avoid the BUILD_BUG_ON() in proc_comm_connector(). Suggested-by: Kees Cook Signed-off-by: Yafang Shao Cc: Vladimir Zapolskiy Cc: Peter Zijlstra Cc: Steven Rostedt Cc: David Howells Cc: Kees Cook Cc: Al Viro Cc: Petr Mladek --- drivers/connector/cn_proc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c index 646ad385e490..c88ba2dc1eae 100644 --- a/drivers/connector/cn_proc.c +++ b/drivers/connector/cn_proc.c @@ -230,7 +230,10 @@ void proc_comm_connector(struct task_struct *task) ev->what = PROC_EVENT_COMM; ev->event_data.comm.process_pid = task->pid; ev->event_data.comm.process_tgid = task->tgid; - get_task_comm(ev->event_data.comm.comm, task); + + /* This may get truncated. */ + __get_task_comm(ev->event_data.comm.comm, + sizeof(ev->event_data.comm.comm), task); memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id)); msg->ack = 0; /* not used */ -- 2.18.2