From patchwork Fri Mar 5 19:26:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris Burkov X-Patchwork-Id: 12119385 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 D6439C433E6 for ; Fri, 5 Mar 2021 19:27:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AA188650A7 for ; Fri, 5 Mar 2021 19:27:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229791AbhCET1T (ORCPT ); Fri, 5 Mar 2021 14:27:19 -0500 Received: from wout1-smtp.messagingengine.com ([64.147.123.24]:44681 "EHLO wout1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229719AbhCET0r (ORCPT ); Fri, 5 Mar 2021 14:26:47 -0500 Received: from compute2.internal (compute2.nyi.internal [10.202.2.42]) by mailout.west.internal (Postfix) with ESMTP id 680BD2B11; Fri, 5 Mar 2021 14:26:46 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Fri, 05 Mar 2021 14:26:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bur.io; h=from :to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; s=fm3; bh=J5FWW5HO3c8kpgrrRaPFjrymDw IfNpVfTtewo+6Gb2M=; b=Iyr+KWOCKDJEiZQi+Wh/0tt5QypxFaHPcw6HpUaHkj MKUODKCCO7nlaytnD5iW8HpNQsPZT3K/pIEcP87H7RCWj0l5OmJLr14dcGb9H4o8 xA6eKuMcLcTy+WNke+sh2+yr+cFoRfnxpe3PUfI7hyRlgjNDQFaDQbpTBmVyBSVG 7xuDzDa6cTOJWkOWq3OMI3P+zJnOOdgmQqEqsuwbkW6FIJ5VAAALR0LH1Odnzbtr hJenGynUFS6Lsdr1fYvKTcckiONtPggD4nwyPPXQzQIw6pgAP0nBeX4GI2l3H4gs nLfV3Og5RFL3uGAnToKXJ0a+g0akH0JgIBy9YwwrhqRA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:subject:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm2; bh=J5FWW5HO3c8kpgrrRaPFjrymDwIfNpVfTtewo+6Gb2M=; b=iC25zTzE awpIbZwQ1yIUd1KSge0USUCpRMVDyJxGQ1zw+utmlfYYlTyzJ9F9OFEYU5pn1GJB LqVaYVMRnrISYTNvXmZ0Hb0nCcjgWZxUP2ayKtIyVPUwiHTnaE04HWDmEvi39amS 60EvlBieqRUBMuwrqVkZ6ESRmxKP1pfb42Hli/3HzULBmk99N+vZFLEuun+7mpl9 HSEKL7aAbIxawv5FLJaHOVsLpKVmS1Pjr0w8k54ze4IMkvnovcRSBsz11Bc7t+K8 7Fr/Kd8NU1TzjZ2RDWSDF7T1ZAPTfxbG2o7Iwl2q8paePZGz8bBgBwL6YieHyrF0 onYcGeGzUT6qmA== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledruddtiedguddugecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd enucfjughrpefhvffufffkofgjfhgggfestdekredtredttdenucfhrhhomhepuehorhhi shcuuehurhhkohhvuceosghorhhishessghurhdrihhoqeenucggtffrrghtthgvrhhnpe eiueffuedvieeujefhheeigfekvedujeejjeffvedvhedtudefiefhkeegueehleenucfk phepudeifedruddugedrudefvddrheenucevlhhushhtvghrufhiiigvpedunecurfgrrh grmhepmhgrihhlfhhrohhmpegsohhrihhssegsuhhrrdhioh X-ME-Proxy: Received: from localhost (unknown [163.114.132.5]) by mail.messagingengine.com (Postfix) with ESMTPA id 3E3231080063; Fri, 5 Mar 2021 14:26:45 -0500 (EST) From: Boris Burkov To: linux-btrfs@vger.kernel.org, kernel-team@fb.com, linux-fscrypt@vger.kernel.org, 'Eric Biggers ' Subject: [PATCH v2 3/5] btrfs: check verity for reads of inline extents and holes Date: Fri, 5 Mar 2021 11:26:31 -0800 Message-Id: X-Mailer: git-send-email 2.24.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org The majority of reads receive a verity check after the bio is complete as the page is marked uptodate. However, there is a class of reads which are handled with btrfs logic in readpage, rather than by submitting a bio. Specifically, these are inline extents, preallocated extents, and holes. Tweak readpage so that if it is going to mark such a page uptodate, it first checks verity on it. Now if a veritied file has corruption to this class of EXTENT_DATA items, it will be detected at read time. There is one annoying edge case that requires checking for start < last_byte: if userspace reads to the end of a file with page aligned size and then tries to keep reading (as cat does), the buffered read code will try to read the page past the end of the file, and expects it to be filled with 0s and marked uptodate. That bogus page is not part of the data hashed by verity, so we have to ignore it. Signed-off-by: Boris Burkov --- fs/btrfs/extent_io.c | 26 +++++++------------------- 1 file changed, 7 insertions(+), 19 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 0d6f8b33830f..653b066f3043 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2201,18 +2201,6 @@ int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end, return bitset; } -/* - * helper function to set a given page up to date if all the - * extents in the tree for that page are up to date - */ -static void check_page_uptodate(struct extent_io_tree *tree, struct page *page) -{ - u64 start = page_offset(page); - u64 end = start + PAGE_SIZE - 1; - if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL)) - SetPageUptodate(page); -} - int free_io_failure(struct extent_io_tree *failure_tree, struct extent_io_tree *io_tree, struct io_failure_record *rec) @@ -3427,14 +3415,14 @@ int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, &cached, GFP_NOFS); unlock_extent_cached(tree, cur, cur + iosize - 1, &cached); - end_page_read(page, true, cur, iosize); + ret = end_page_read(page, true, cur, iosize); break; } em = __get_extent_map(inode, page, pg_offset, cur, end - cur + 1, em_cached); if (IS_ERR_OR_NULL(em)) { unlock_extent(tree, cur, end); - end_page_read(page, false, cur, end + 1 - cur); + ret = end_page_read(page, false, cur, end + 1 - cur); break; } extent_offset = cur - em->start; @@ -3515,9 +3503,10 @@ int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, set_extent_uptodate(tree, cur, cur + iosize - 1, &cached, GFP_NOFS); + unlock_extent_cached(tree, cur, cur + iosize - 1, &cached); - end_page_read(page, true, cur, iosize); + ret = end_page_read(page, true, cur, iosize); cur = cur + iosize; pg_offset += iosize; continue; @@ -3525,9 +3514,8 @@ int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, /* the get_extent function already copied into the page */ if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1, NULL)) { - check_page_uptodate(tree, page); unlock_extent(tree, cur, cur + iosize - 1); - end_page_read(page, true, cur, iosize); + ret = end_page_read(page, true, cur, iosize); cur = cur + iosize; pg_offset += iosize; continue; @@ -3537,7 +3525,7 @@ int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, */ if (block_start == EXTENT_MAP_INLINE) { unlock_extent(tree, cur, cur + iosize - 1); - end_page_read(page, false, cur, iosize); + ret = end_page_read(page, false, cur, iosize); cur = cur + iosize; pg_offset += iosize; continue; @@ -3555,7 +3543,7 @@ int btrfs_do_readpage(struct page *page, struct extent_map **em_cached, *bio_flags = this_bio_flag; } else { unlock_extent(tree, cur, cur + iosize - 1); - end_page_read(page, false, cur, iosize); + ret = end_page_read(page, false, cur, iosize); goto out; } cur = cur + iosize;