From patchwork Fri Oct 18 18:43:39 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 13842225 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 835FF205AA3; Fri, 18 Oct 2024 18:45:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729277106; cv=none; b=IhxKmKAgea+SJzh7rQ5iGFcBwPa6+W54uzZBimWL7VpAq5rJ1zP+qwmZ98Wo11Xm+MnRuO42jsAqC3E7lPbcEMRDvgZy6h41E52qXkERAmO7AJ/yT4Tag2WAMlt7tWbi1cZLJR/GkK7cj5N1OXMg+wUkDZ2IpQmbFke91sBWf6k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729277106; c=relaxed/simple; bh=CJqMmKGmlMC1ZgTSvCsZDhV/pMMcxUr0PbmDF9R/3J8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AtXgYBdH2gz0eSbBuS+FGeAvLWadoZ5k7cFdZiFFUge1YrCpAtgVsvjpxNWon0kkLUuPNxhJteqKWweg9asNLRRzUurw3gT2OeVsqNFvekS+OrzTEZQIcMpN6NoTSnTsrvJjKWvZf1D8/kAIIjqrRzqXi5SBJ8FCpaFJ9k3VGEE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Tb8QNDbB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Tb8QNDbB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0401DC4CED2; Fri, 18 Oct 2024 18:45:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729277106; bh=CJqMmKGmlMC1ZgTSvCsZDhV/pMMcxUr0PbmDF9R/3J8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Tb8QNDbBm1c5jVfWGHeTX79arz2h6WihIiGeGNIT1wKOvl2SnsoxQny2qbD9K1FS5 97IPTYhanx0dVA/KlRGXyEAFlT3qZc5C3vmIG1rDfkSH2LyQaUiCnmtuIj6YD37F5h g4WCzHrK0wC5FDmW5iezMTH7eAeEg/CHLKAH4Qp9fiamrAYfzwxlebwnZvFSKbxHAk yiQDNBYnN+xJV0CVw+2R+YJrgal7feu2DQYXE0AETmCZ4+krXjiiwSrmpxVeK46w6g MrU3gjK5ZqSFodlQJ5Ej0BiLUESxaSHZ8BqiviYFBDcr65dFbbHe+Yxb9T66VX434g 9ZMlF7J4BWWWg== From: Eric Biggers To: dm-devel@lists.linux.dev Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fscrypt@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Md Sadre Alam , Israel Rukshin , Milan Broz , Mikulas Patocka , Adrian Vovk Subject: [RFC PATCH 4/4] ext4,f2fs: support metadata encryption via dm-default-key Date: Fri, 18 Oct 2024 11:43:39 -0700 Message-ID: <20241018184339.66601-5-ebiggers@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241018184339.66601-1-ebiggers@kernel.org> References: <20241018184339.66601-1-ebiggers@kernel.org> Precedence: bulk X-Mailing-List: linux-fscrypt@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Eric Biggers Set the bi_skip_dm_default_key flag on bios that are targeting the contents of an encrypted file and therefore should not be en/decrypted by dm-default-key. Signed-off-by: Eric Biggers --- fs/crypto/inline_crypt.c | 14 +++++++++++++- fs/f2fs/data.c | 6 +++++- include/linux/fscrypt.h | 14 ++++++++++++++ 3 files changed, 32 insertions(+), 2 deletions(-) diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c index 40de69860dcf9..b75c69c09500b 100644 --- a/fs/crypto/inline_crypt.c +++ b/fs/crypto/inline_crypt.c @@ -261,17 +261,22 @@ static void fscrypt_generate_dun(const struct fscrypt_inode_info *ci, * * Normally the bio should be newly allocated (i.e. no pages added yet), as * otherwise fscrypt_mergeable_bio() won't work as intended. * * The encryption context will be freed automatically when the bio is freed. + * + * This function also handles setting bi_skip_dm_default_key when needed. */ void fscrypt_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode, u64 first_lblk, gfp_t gfp_mask) { const struct fscrypt_inode_info *ci; u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE]; + if (fscrypt_inode_should_skip_dm_default_key(inode)) + bio_set_skip_dm_default_key(bio); + if (!fscrypt_inode_uses_inline_crypto(inode)) return; ci = inode->i_crypt_info; fscrypt_generate_dun(ci, first_lblk, dun); @@ -342,20 +347,26 @@ EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx_bh); * * This function isn't required in cases where crypto-mergeability is ensured in * another way, such as I/O targeting only a single file (and thus a single key) * combined with fscrypt_limit_io_blocks() to ensure DUN contiguity. * + * This function also returns false if the next part of the I/O would need to + * have a different value for the bi_skip_dm_default_key flag. + * * Return: true iff the I/O is mergeable */ bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode, u64 next_lblk) { const struct bio_crypt_ctx *bc = bio->bi_crypt_context; u64 next_dun[BLK_CRYPTO_DUN_ARRAY_SIZE]; if (!!bc != fscrypt_inode_uses_inline_crypto(inode)) return false; + if (bio_should_skip_dm_default_key(bio) != + fscrypt_inode_should_skip_dm_default_key(inode)) + return false; if (!bc) return true; /* * Comparing the key pointers is good enough, as all I/O for each key @@ -385,11 +396,12 @@ bool fscrypt_mergeable_bio_bh(struct bio *bio, { const struct inode *inode; u64 next_lblk; if (!bh_get_inode_and_lblk_num(next_bh, &inode, &next_lblk)) - return !bio->bi_crypt_context; + return !bio->bi_crypt_context && + !bio_should_skip_dm_default_key(bio); return fscrypt_mergeable_bio(bio, inode, next_lblk); } EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio_bh); diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 94f7b084f6016..a413508210994 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -484,10 +484,12 @@ static void f2fs_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode, * The f2fs garbage collector sets ->encrypted_page when it wants to * read/write raw data without encryption. */ if (!fio || !fio->encrypted_page) fscrypt_set_bio_crypt_ctx(bio, inode, first_idx, gfp_mask); + else if (fscrypt_inode_should_skip_dm_default_key(inode)) + bio_set_skip_dm_default_key(bio); } static bool f2fs_crypt_mergeable_bio(struct bio *bio, const struct inode *inode, pgoff_t next_idx, const struct f2fs_io_info *fio) @@ -495,11 +497,13 @@ static bool f2fs_crypt_mergeable_bio(struct bio *bio, const struct inode *inode, /* * The f2fs garbage collector sets ->encrypted_page when it wants to * read/write raw data without encryption. */ if (fio && fio->encrypted_page) - return !bio_has_crypt_ctx(bio); + return !bio_has_crypt_ctx(bio) && + (bio_should_skip_dm_default_key(bio) == + fscrypt_inode_should_skip_dm_default_key(inode)); return fscrypt_mergeable_bio(bio, inode, next_idx); } void f2fs_submit_read_bio(struct f2fs_sb_info *sbi, struct bio *bio, diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h index 772f822dc6b82..eac1917db79a9 100644 --- a/include/linux/fscrypt.h +++ b/include/linux/fscrypt.h @@ -890,10 +890,24 @@ static inline u64 fscrypt_limit_io_blocks(const struct inode *inode, u64 lblk, { return nr_blocks; } #endif /* !CONFIG_FS_ENCRYPTION_INLINE_CRYPT */ +#if IS_ENABLED(CONFIG_FS_ENCRYPTION) && IS_ENABLED(CONFIG_DM_DEFAULT_KEY) +static inline bool +fscrypt_inode_should_skip_dm_default_key(const struct inode *inode) +{ + return IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode); +} +#else +static inline bool +fscrypt_inode_should_skip_dm_default_key(const struct inode *inode) +{ + return false; +} +#endif + /** * fscrypt_inode_uses_inline_crypto() - test whether an inode uses inline * encryption * @inode: an inode. If encrypted, its key must be set up. *