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=-18.7 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 F3ACDC43470 for ; Thu, 8 Apr 2021 18:34:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C92A8610FC for ; Thu, 8 Apr 2021 18:34:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232832AbhDHSeO (ORCPT ); Thu, 8 Apr 2021 14:34:14 -0400 Received: from wout5-smtp.messagingengine.com ([64.147.123.21]:41111 "EHLO wout5-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232608AbhDHSeO (ORCPT ); Thu, 8 Apr 2021 14:34:14 -0400 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.west.internal (Postfix) with ESMTP id 8088ED40; Thu, 8 Apr 2021 14:34:02 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute4.internal (MEProxy); Thu, 08 Apr 2021 14:34:02 -0400 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=N20CXryfB2nGoFxRclfcVkf9Fv xw9P7I4zlwZ715vks=; b=NAQ7eCklW/aDM9qpkleYp5wT6L2GZyJaN9lWkX5Th1 DfJVzunDmJsy6wbQLnhVpXyJh6EHC1lmJrnRmWchUep5UJH+uAWN+M8mnZPKU1Oc eyCGWBpdcWlX+cHZY4u8ML/UI3FPjov6kPYja6VD2aoblegaQczvZcH809a5pbd6 zCGQ5+SHxb2OE6AKKtTZkYaIEnVBXtSRrqyosEvEpYP+O9JSmgrlD8RIqf+JIJ7p V/1RwEOShVURpfJxQeyK+fUah85OgPi8Acxst1OrB/kKLj4VJJ4LkQrGa97KlVF/ +ZY4Q1djfQNzctvYZoJSy7KFtNAdBaLtbApW/Nbo/dNQ== 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=N20CXryfB2nGoFxRclfcVkf9Fvxw9P7I4zlwZ715vks=; b=tNwcHom/ cDbe9rcyuzXP5uxPAApAYcoXB9KhJnzJK5tyw2z4JQnRyatXEERqLS7xvxwK5l/a ZphL2QOPLe3hPz96WmvERmgh2n2MY2hUlFWFyjsRTgkao6WdMRxpkg/EpwDppSHx JtehI+jc13P5jfZ2r/3RBETKxCBlt5EH1oQ9YHwjo9QboJaV9wAi38+mWE7ROX/+ 6Fl1HnziSFxfbS9sY3SThNoN4BHsDgJSfy096twJJyS20ImbcwXpot04Isi9Md5n 2r4abtqq/eKg3OvinTTxHM2MDvhbOMFbjrH7u48tC7N4mp0uJ5se7AwIrI69r0FN eq2h+B+S/ocDDQ== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledrudejledguddvkecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecunecujfgurhephffvufffkffojghfggfgsedtke ertdertddtnecuhfhrohhmpeeuohhrihhsuceuuhhrkhhovhcuoegsohhrihhssegsuhhr rdhioheqnecuggftrfgrthhtvghrnhepieeuffeuvdeiueejhfehiefgkeevudejjeejff evvdehtddufeeihfekgeeuheelnecukfhppedvtdejrdehfedrvdehfedrjeenucevlhhu shhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpegsohhrihhssegsuh hrrdhioh X-ME-Proxy: Received: from localhost (unknown [207.53.253.7]) by mail.messagingengine.com (Postfix) with ESMTPA id E144A1080057; Thu, 8 Apr 2021 14:34:01 -0400 (EDT) From: Boris Burkov To: linux-btrfs@vger.kernel.org, kernel-team@fb.com, linux-fscrypt@vger.kernel.org Subject: [PATCH v3 3/5] btrfs: check verity for reads of inline extents and holes Date: Thu, 8 Apr 2021 11:33:54 -0700 Message-Id: <533e9f42d156fa2bd27b28c0c62a956e3245f3b9.1617900170.git.boris@bur.io> X-Mailer: git-send-email 2.30.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 bf784c10040b..a15f289e29e6 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2202,18 +2202,6 @@ 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) @@ -3467,14 +3455,14 @@ 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; @@ -3555,9 +3543,10 @@ 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; @@ -3565,9 +3554,8 @@ 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; @@ -3577,7 +3565,7 @@ 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; @@ -3595,7 +3583,7 @@ 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; -- 2.30.2