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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 D5606C2D0E4 for ; Tue, 17 Nov 2020 13:17:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82097241A6 for ; Tue, 17 Nov 2020 13:17:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="tVzFVRAg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729917AbgKQNRA (ORCPT ); Tue, 17 Nov 2020 08:17:00 -0500 Received: from mail.kernel.org ([198.145.29.99]:49138 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729782AbgKQNQ6 (ORCPT ); Tue, 17 Nov 2020 08:16:58 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 85C13206D5; Tue, 17 Nov 2020 13:16:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605619018; bh=Ath5HiLb+Ur+ryUqN182/0Y5RZXzARERCr1b6+NLivk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tVzFVRAg3v5gRWCpAVfA0S1Gza/3UZYHhwFUGTvhyQnBJhx0kjRDsYyFmwOOOSsvA KIr8xerQNPMi27RKXThzTVg2y34qeJoax+rna2AyNZgVR2MWA22vbwqy5XNOZqpBLu 2GezHcfR4c1H3l5kLhSdcp3kJMFThkLND+KMqfRs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?kiyin ?= , Dan Carpenter , Ingo Molnar , "Srivatsa S. Bhat" , Anthony Liguori , Sudip Mukherjee Subject: [PATCH 4.14 68/85] perf/core: Fix a memory leak in perf_event_parse_addr_filter() Date: Tue, 17 Nov 2020 14:05:37 +0100 Message-Id: <20201117122114.364908010@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201117122111.018425544@linuxfoundation.org> References: <20201117122111.018425544@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: "kiyin(尹亮)" commit 7bdb157cdebbf95a1cd94ed2e01b338714075d00 upstream As shown through runtime testing, the "filename" allocation is not always freed in perf_event_parse_addr_filter(). There are three possible ways that this could happen: - It could be allocated twice on subsequent iterations through the loop, - or leaked on the success path, - or on the failure path. Clean up the code flow to make it obvious that 'filename' is always freed in the reallocation path and in the two return paths as well. We rely on the fact that kfree(NULL) is NOP and filename is initialized with NULL. This fixes the leak. No other side effects expected. [ Dan Carpenter: cleaned up the code flow & added a changelog. ] [ Ingo Molnar: updated the changelog some more. ] Fixes: 375637bc5249 ("perf/core: Introduce address range filtering") Signed-off-by: "kiyin(尹亮)" Signed-off-by: Dan Carpenter Signed-off-by: Ingo Molnar Cc: "Srivatsa S. Bhat" Cc: Anthony Liguori Signed-off-by: Sudip Mukherjee Signed-off-by: Greg Kroah-Hartman --- kernel/events/core.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8581,6 +8581,7 @@ perf_event_parse_addr_filter(struct perf if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { int fpos = filter->range ? 2 : 1; + kfree(filename); filename = match_strdup(&args[fpos]); if (!filename) { ret = -ENOMEM; @@ -8619,16 +8620,13 @@ perf_event_parse_addr_filter(struct perf */ ret = -EOPNOTSUPP; if (!event->ctx->task) - goto fail_free_name; + goto fail; /* look up the path and grab its inode */ ret = kern_path(filename, LOOKUP_FOLLOW, &filter->path); if (ret) - goto fail_free_name; - - kfree(filename); - filename = NULL; + goto fail; ret = -EINVAL; if (!filter->path.dentry || @@ -8648,13 +8646,13 @@ perf_event_parse_addr_filter(struct perf if (state != IF_STATE_ACTION) goto fail; + kfree(filename); kfree(orig); return 0; -fail_free_name: - kfree(filename); fail: + kfree(filename); free_filters_list(filters); kfree(orig);