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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 E5005C43381 for ; Fri, 22 Mar 2019 12:04:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A541E2192D for ; Fri, 22 Mar 2019 12:04:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553256293; bh=RgMJnDERoQkrmyDxnu9lN5+W5E0bHSSz56wUoDZ245k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=VHX3+tzjgaoCXUZCESo4uov4aD/oeGsPfyTQko6a/L7Ilh02aSz4jil/p5/h37m7D 63yenq3f9F0WDpZsjmDXGGctJ/5cXL0DtZiTOq0/gAdK3+YU9Vc2eYM5VwGi7/l9nK SjL4BSxFpqAe+dKZY2mDyrqrL742NHDTbxcq9HAE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388727AbfCVMEw (ORCPT ); Fri, 22 Mar 2019 08:04:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:43230 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733252AbfCVMEt (ORCPT ); Fri, 22 Mar 2019 08:04:49 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 86757206C0; Fri, 22 Mar 2019 12:04:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553256289; bh=RgMJnDERoQkrmyDxnu9lN5+W5E0bHSSz56wUoDZ245k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=k8NFNIWFyrWzAvUp29mQm+iCiEr4ZodO+1skpN86Qqs0T6u50QIxebbaLYGwXckQg oE+FPHjaaE9AmteYLvbaAPWh6e8he9aZnQe/JDCnj72Z810mSXLzcdvk1MPMV7CcIZ 89FOv3A03Ev2NOk/gIZuz4Z9c7J/PsApJWapmPOU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ingo Molnar , Masami Hiramatsu , Song Liu , Jann Horn , "Steven Rostedt (VMware)" Subject: [PATCH 4.19 142/280] tracing/perf: Use strndup_user() instead of buggy open-coded version Date: Fri, 22 Mar 2019 12:14:55 +0100 Message-Id: <20190322111318.570881793@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111306.356185024@linuxfoundation.org> References: <20190322111306.356185024@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jann Horn commit 83540fbc8812a580b6ad8f93f4c29e62e417687e upstream. The first version of this method was missing the check for `ret == PATH_MAX`; then such a check was added, but it didn't call kfree() on error, so there was still a small memory leak in the error case. Fix it by using strndup_user() instead of open-coding it. Link: http://lkml.kernel.org/r/20190220165443.152385-1-jannh@google.com Cc: Ingo Molnar Cc: stable@vger.kernel.org Fixes: 0eadcc7a7bc0 ("perf/core: Fix perf_uprobe_init()") Reviewed-by: Masami Hiramatsu Acked-by: Song Liu Signed-off-by: Jann Horn Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_event_perf.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -298,15 +298,13 @@ int perf_uprobe_init(struct perf_event * if (!p_event->attr.uprobe_path) return -EINVAL; - path = kzalloc(PATH_MAX, GFP_KERNEL); - if (!path) - return -ENOMEM; - ret = strncpy_from_user( - path, u64_to_user_ptr(p_event->attr.uprobe_path), PATH_MAX); - if (ret == PATH_MAX) - return -E2BIG; - if (ret < 0) - goto out; + + path = strndup_user(u64_to_user_ptr(p_event->attr.uprobe_path), + PATH_MAX); + if (IS_ERR(path)) { + ret = PTR_ERR(path); + return (ret == -EINVAL) ? -E2BIG : ret; + } if (path[0] == '\0') { ret = -EINVAL; goto out;