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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,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 D20DDC0650F for ; Mon, 5 Aug 2019 13:28:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A88FC20651 for ; Mon, 5 Aug 2019 13:28:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565011702; bh=fqemhpUHz98YQxmGNMTN+N12UlsgJGrB4v2R7xmi2JY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RExlCHxGc+UnOGEPPyEJlDwfJDiBEd7NYWTC6sweqBJfrZIFHbCpAs7RO5gpHVRmV QqxhDAocdYz+Hme4wNhkw7amj/umzTJ3xs+Vk9IViO/+s3zw1sr0fYszrBkGB3yusn BapkA6EEc8MzYj37loQuDIQne1HU8mFNiJY6eeQE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730595AbfHENXd (ORCPT ); Mon, 5 Aug 2019 09:23:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:60198 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730345AbfHENXc (ORCPT ); Mon, 5 Aug 2019 09:23:32 -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 144D72075B; Mon, 5 Aug 2019 13:23:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565011411; bh=fqemhpUHz98YQxmGNMTN+N12UlsgJGrB4v2R7xmi2JY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=msoeJftOH48RTAmP4tP9Xu/bPQclZK+lz5CV/NZYyJI3QNdDkQRyNlctCug/RiTru 7hFKWdm701KtQbCQQgFqAgXqlr0GIL1nKwhxYDJd3KpOuXjWOQsHmFCp/FpmeJYHdq NhHoR6ayrUdBApIEn9i3naItnatYa63jBIy8VOxQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vitaly Wool , Henry Burns , Shakeel Butt , Jonathan Adams , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 5.2 047/131] mm/z3fold: dont try to use buddy slots after free Date: Mon, 5 Aug 2019 15:02:14 +0200 Message-Id: <20190805124954.583410174@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190805124951.453337465@linuxfoundation.org> References: <20190805124951.453337465@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit bb9a374dfa3a2f46581455ab66cd1d24c5e3d183 ] As reported by Henry Burns: Running z3fold stress testing with address sanitization showed zhdr->slots was being used after it was freed. z3fold_free(z3fold_pool, handle) free_handle(handle) kmem_cache_free(pool->c_handle, zhdr->slots) release_z3fold_page_locked_list(kref) __release_z3fold_page(zhdr, true) zhdr_to_pool(zhdr) slots_to_pool(zhdr->slots) *BOOM* To fix this, add pointer to the pool back to z3fold_header and modify zhdr_to_pool to return zhdr->pool. Link: http://lkml.kernel.org/r/20190708134808.e89f3bfadd9f6ffd7eff9ba9@gmail.com Fixes: 7c2b8baa61fe ("mm/z3fold.c: add structure for buddy handles") Signed-off-by: Vitaly Wool Reported-by: Henry Burns Reviewed-by: Shakeel Butt Cc: Jonathan Adams Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/z3fold.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/z3fold.c b/mm/z3fold.c index dfcd69d08c1e9..304f2883cdb93 100644 --- a/mm/z3fold.c +++ b/mm/z3fold.c @@ -101,6 +101,7 @@ struct z3fold_buddy_slots { * @refcount: reference count for the z3fold page * @work: work_struct for page layout optimization * @slots: pointer to the structure holding buddy slots + * @pool: pointer to the containing pool * @cpu: CPU which this page "belongs" to * @first_chunks: the size of the first buddy in chunks, 0 if free * @middle_chunks: the size of the middle buddy in chunks, 0 if free @@ -114,6 +115,7 @@ struct z3fold_header { struct kref refcount; struct work_struct work; struct z3fold_buddy_slots *slots; + struct z3fold_pool *pool; short cpu; unsigned short first_chunks; unsigned short middle_chunks; @@ -320,6 +322,7 @@ static struct z3fold_header *init_z3fold_page(struct page *page, zhdr->start_middle = 0; zhdr->cpu = -1; zhdr->slots = slots; + zhdr->pool = pool; INIT_LIST_HEAD(&zhdr->buddy); INIT_WORK(&zhdr->work, compact_page_work); return zhdr; @@ -426,7 +429,7 @@ static enum buddy handle_to_buddy(unsigned long handle) static inline struct z3fold_pool *zhdr_to_pool(struct z3fold_header *zhdr) { - return slots_to_pool(zhdr->slots); + return zhdr->pool; } static void __release_z3fold_page(struct z3fold_header *zhdr, bool locked) -- 2.20.1