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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 875A9C433ED for ; Mon, 5 Apr 2021 16:04:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5C65F613CC for ; Mon, 5 Apr 2021 16:04:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241928AbhDEQEr (ORCPT ); Mon, 5 Apr 2021 12:04:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:55626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241988AbhDEQEW (ORCPT ); Mon, 5 Apr 2021 12:04:22 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 87C77613C5; Mon, 5 Apr 2021 16:04:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617638656; bh=O+/UHaBVwZ0Em9A4LOIifx0V4lI/JkxP/Cl96bfofRY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mdumTZMIJUaoQYlE9p3AOOx13/cbiSGLGnDyGDQhwV6x6uUBC8eiUU6Q3+4idQsar OoNgePy/8K382g0yXzMXsE/KgbiMgHg2yVO1jEX4Jtf+uMlHg2B7hqILskBn8sVVEH 2YWjbQ0MKiLTQqwxfYvMAljZRhlmC10OrFbbuNIjcLbB78s6DBI+YzhhfHrGo3A3bI dGGS2err0x9lf3CqYSToIlQHlV9p03Fmqk7VUIv/EKvuLCpea6Wo2VWZR48iLZBrLG Ehy0ZqT0fJTkWnWNiCZ35aW8XqWT0pEAiMgYkoC6dynDrpeNSC2txG1ooEIexzk8fY AMWgw3zsNpzBA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Steven Rostedt (VMware)" , Abaci Robot , Sasha Levin Subject: [PATCH AUTOSEL 5.11 08/22] ftrace: Check if pages were allocated before calling free_pages() Date: Mon, 5 Apr 2021 12:03:51 -0400 Message-Id: <20210405160406.268132-8-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210405160406.268132-1-sashal@kernel.org> References: <20210405160406.268132-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Steven Rostedt (VMware)" [ Upstream commit 59300b36f85f254260c81d9dd09195fa49eb0f98 ] It is possible that on error pg->size can be zero when getting its order, which would return a -1 value. It is dangerous to pass in an order of -1 to free_pages(). Check if order is greater than or equal to zero before calling free_pages(). Link: https://lore.kernel.org/lkml/20210330093916.432697c7@gandalf.local.home/ Reported-by: Abaci Robot Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Sasha Levin --- kernel/trace/ftrace.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index b7e29db127fa..3ba52d4e1314 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3231,7 +3231,8 @@ ftrace_allocate_pages(unsigned long num_to_init) pg = start_pg; while (pg) { order = get_count_order(pg->size / ENTRIES_PER_PAGE); - free_pages((unsigned long)pg->records, order); + if (order >= 0) + free_pages((unsigned long)pg->records, order); start_pg = pg->next; kfree(pg); pg = start_pg; @@ -6451,7 +6452,8 @@ void ftrace_release_mod(struct module *mod) clear_mod_from_hashes(pg); order = get_count_order(pg->size / ENTRIES_PER_PAGE); - free_pages((unsigned long)pg->records, order); + if (order >= 0) + free_pages((unsigned long)pg->records, order); tmp_page = pg->next; kfree(pg); ftrace_number_of_pages -= 1 << order; @@ -6811,7 +6813,8 @@ void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) if (!pg->index) { *last_pg = pg->next; order = get_count_order(pg->size / ENTRIES_PER_PAGE); - free_pages((unsigned long)pg->records, order); + if (order >= 0) + free_pages((unsigned long)pg->records, order); ftrace_number_of_pages -= 1 << order; ftrace_number_of_groups--; kfree(pg); -- 2.30.2