From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C99813921DB; Tue, 6 Oct 2026 21:38:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791322729; cv=none; b=VuywxvNYNc/3Fydjby3yzc6g4x2NbWuQhTCd+GZlzYASVgmDh9RAhyTnjJ8Ld70n3bz6X/nAhDHIOyt8JLyRsl4gopZocpvbfbho6xHnDT/C5/nwrf1CLuSM8oP+9jmrryE/q/Uagwu7W/yxN2PIoAUn8I406Jwie5oKF095iFc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791322729; c=relaxed/simple; bh=sLVYMQ3a+JCcJqtqkuSzgc7Dv/99jDYczIj2qFb2Bws=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mc9o4DL+ha3nhaMMNfATlQoWvSOxaDo7PIvgtQR3TZBXEzdVNV/c/Sg6ZWP2GyNbh6wmBIULZnThGdhGs+Nooizd28u2xvLHQBffSCQDr0oWNl4EOgt7wtCawn9XDIxdJ5DvYRosc9zuDsxbhigYhTO1t7hQACJFKNA5M/UPtcI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ajaPjFq4; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ajaPjFq4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 403411F0089C; Tue, 6 Oct 2026 21:38:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791322727; bh=u5jL38FIPqgUMtJ7q9hBSTn4S/uCbRxrlnTcbfQynSQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ajaPjFq47zfK7YPEwdT08LmMkmO2GXcWy+oQMxHcW4lLQ47SW12FpHewvCQFzqZSD vp1Jc/D+8Q41yPur3bd2TyMHIi/I80VNnISzbIAOcbkDMam1nqQDEEbAR7kFW1HusB meezoXUNIzMghkTwaFc1WE4v2pOZLdVWoeywUs/jVgFFLukYclXh1vMQALpbFRSamV 6so2HpqTs7CKX0SI+KMAGWvHtcDMwCYcmQ7evr/a4p6DElxl4Si+ft9/AUPrsXjsAS f4GSTHqYiTbjPJvKPv3alyb0XltRbqamJ27N/u7SKqig6hL5iB2qoPU6flMWzrlZfa Nmemc0ar9Ze6Q== From: Eric Biggers To: stable@vger.kernel.org Cc: fsverity@lists.linux.dev, linux-btrfs@vger.kernel.org, Christoph Hellwig , Jan Kara , "Darrick J. Wong" , Eric Biggers Subject: [PATCH 6.6 1/2] fs,fsverity: reject size changes on fsverity files in setattr_prepare Date: Tue, 6 Oct 2026 23:38:14 +0200 Message-ID: <20261006213815.47194-2-ebiggers@kernel.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261006213815.47194-1-ebiggers@kernel.org> References: <20261006213815.47194-1-ebiggers@kernel.org> Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Christoph Hellwig commit e9734653c523c744f03333ece6ae7a315187f05c upstream. Add the check to reject truncates of fsverity files directly to setattr_prepare instead of requiring the file system to handle it. Besides removing boilerplate code, this also fixes the complete lack of such check in btrfs. Fixes: 146054090b08 ("btrfs: initial fsverity support") Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: "Darrick J. Wong" Link: https://lore.kernel.org/r/20260128152630.627409-2-hch@lst.de Signed-off-by: Eric Biggers --- fs/attr.c | 12 +++++++++++- fs/ext4/inode.c | 4 ---- fs/f2fs/file.c | 4 ---- fs/verity/open.c | 8 -------- include/linux/fsverity.h | 25 ------------------------- 5 files changed, 11 insertions(+), 42 deletions(-) diff --git a/fs/attr.c b/fs/attr.c index a8ae5f6d9b16..c2302fc4b333 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -173,7 +173,17 @@ int setattr_prepare(struct mnt_idmap *idmap, struct dentry *dentry, * ATTR_FORCE. */ if (ia_valid & ATTR_SIZE) { - int error = inode_newsize_ok(inode, attr->ia_size); + int error; + + /* + * Verity files are immutable, so deny truncates. This isn't + * covered by the open-time check because sys_truncate() takes a + * path, not an open file. + */ + if (IS_ENABLED(CONFIG_FS_VERITY) && IS_VERITY(inode)) + return -EPERM; + + error = inode_newsize_ok(inode, attr->ia_size); if (error) return error; } diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index dea6d27e5028..9ff2958509ed 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5484,10 +5484,6 @@ int ext4_setattr(struct mnt_idmap *idmap, struct dentry *dentry, if (error) return error; - error = fsverity_prepare_setattr(dentry, attr); - if (error) - return error; - if (is_quota_modification(idmap, inode, attr)) { error = dquot_initialize(inode); if (error) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 7125117b6322..c1cd6dadabfe 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1065,10 +1065,6 @@ int f2fs_setattr(struct mnt_idmap *idmap, struct dentry *dentry, if (err) return err; - err = fsverity_prepare_setattr(dentry, attr); - if (err) - return err; - if (unlikely(IS_IMMUTABLE(inode))) return -EPERM; diff --git a/fs/verity/open.c b/fs/verity/open.c index 6c31a871b84b..5342a8e1f781 100644 --- a/fs/verity/open.c +++ b/fs/verity/open.c @@ -393,14 +393,6 @@ int __fsverity_file_open(struct inode *inode, struct file *filp) } EXPORT_SYMBOL_GPL(__fsverity_file_open); -int __fsverity_prepare_setattr(struct dentry *dentry, struct iattr *attr) -{ - if (attr->ia_valid & ATTR_SIZE) - return -EPERM; - return 0; -} -EXPORT_SYMBOL_GPL(__fsverity_prepare_setattr); - void __fsverity_cleanup_inode(struct inode *inode) { fsverity_free_info(inode->i_verity_info); diff --git a/include/linux/fsverity.h b/include/linux/fsverity.h index 1eb7eae580be..139a6f5c6217 100644 --- a/include/linux/fsverity.h +++ b/include/linux/fsverity.h @@ -149,7 +149,6 @@ int fsverity_get_digest(struct inode *inode, /* open.c */ int __fsverity_file_open(struct inode *inode, struct file *filp); -int __fsverity_prepare_setattr(struct dentry *dentry, struct iattr *attr); void __fsverity_cleanup_inode(struct inode *inode); /** @@ -214,12 +213,6 @@ static inline int __fsverity_file_open(struct inode *inode, struct file *filp) return -EOPNOTSUPP; } -static inline int __fsverity_prepare_setattr(struct dentry *dentry, - struct iattr *attr) -{ - return -EOPNOTSUPP; -} - static inline void fsverity_cleanup_inode(struct inode *inode) { } @@ -301,22 +294,4 @@ static inline int fsverity_file_open(struct inode *inode, struct file *filp) return 0; } -/** - * fsverity_prepare_setattr() - prepare to change a verity inode's attributes - * @dentry: dentry through which the inode is being changed - * @attr: attributes to change - * - * Verity files are immutable, so deny truncates. This isn't covered by the - * open-time check because sys_truncate() takes a path, not a file descriptor. - * - * Return: 0 on success, -errno on failure - */ -static inline int fsverity_prepare_setattr(struct dentry *dentry, - struct iattr *attr) -{ - if (IS_VERITY(d_inode(dentry))) - return __fsverity_prepare_setattr(dentry, attr); - return 0; -} - #endif /* _LINUX_FSVERITY_H */ -- 2.56.0