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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,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 8CC63C43387 for ; Fri, 18 Jan 2019 04:45:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 581D22087E for ; Fri, 18 Jan 2019 04:45:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547786747; bh=jPcC/iWq22RN+kkM1eEvKtM2DfXGIDNHIX0V8Eyhm7M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2AVDFIVaQqOVn9rDAsTwXJg38HZnD3EvNZ73Xxmp+oay6NqSm1cD1DM4ij4QgG8WM u/8Fzhwer8HUB5Pu1oF8MhW5DGrHi1U/vwYDeH3P1COwieZ6V2n4HfpkGW5Q+FQAdF pIOEFpbfWAc0LceEsWvs0pklvE0vQitZkFTRRLZI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727233AbfAREpp (ORCPT ); Thu, 17 Jan 2019 23:45:45 -0500 Received: from mail.kernel.org ([198.145.29.99]:56648 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727009AbfAREpp (ORCPT ); Thu, 17 Jan 2019 23:45:45 -0500 Received: from localhost.localdomain (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1EE942086D; Fri, 18 Jan 2019 04:45:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547786745; bh=jPcC/iWq22RN+kkM1eEvKtM2DfXGIDNHIX0V8Eyhm7M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sVHFZt0tWobqrnUEPRt15mf5hKCJ4lLTzu+YbsxkEFMweox69mOLXBX1pZkd87d0Z WQaX6TAwNSTR3LFET7ATf28iiB5KqhqDnP5++69V3DxJMu7ev/APLQGNYpik+AAxBm EunW2PzEmQWPShmnnWXLHkK8Q7fV54/JKaQKu+tI= From: Masami Hiramatsu To: Steven Rostedt Cc: Andreas Ziegler , Masami Hiramatsu , Ingo Molnar , linux-kernel@vger.kernel.org Subject: [PATCH v2 3/3] tracing: probeevent: Fix to make the type of $comm string Date: Fri, 18 Jan 2019 13:45:22 +0900 Message-Id: <154778672210.19927.871647535916796323.stgit@devbox> X-Mailer: git-send-email 2.13.6 In-Reply-To: <154778663676.19927.12774448308165809570.stgit@devbox> References: <154778663676.19927.12774448308165809570.stgit@devbox> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fix to make the type of $comm "string". If we set the other type to $comm argument, it shows meaningless value or wrong data. Currently probe events allow us to set string array type (e.g. ":string[2]"), or other digit types like x8 on $comm. But since clearly $comm is just a string data, it should not be fetched by other types including array. Fixes: 35abb67de744 ("tracing: expose current->comm to [ku]probe events") Signed-off-by: Masami Hiramatsu Cc: stable@vger.kernel.org --- kernel/trace/trace_probe.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 9962cb5da8ac..44f078cda0ac 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -405,13 +405,14 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size, return -E2BIG; } } - /* - * The default type of $comm should be "string", and it can't be - * dereferenced. - */ - if (!t && strcmp(arg, "$comm") == 0) + + /* Since $comm can not be dereferred, we can find $comm by strcmp */ + if (strcmp(arg, "$comm") == 0) { + /* The type of $comm must be "string", and not an array. */ + if (parg->count || (t && strcmp(t, "string"))) + return -EINVAL; parg->type = find_fetch_type("string"); - else + } else parg->type = find_fetch_type(t); if (!parg->type) { pr_info("Unsupported type: %s\n", t);