From mboxrd@z Thu Jan 1 00:00:00 1970 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 A7C9F30DEC7 for ; Mon, 26 Jan 2026 11:57:21 +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=1769428641; cv=none; b=NdJ/a+UIey3EcoJCK+CTmn92j1DBGWEL6qrJ1s5lafN6mZsCeBYEjo/MhvcAsx8IAvleiZhi019ow91V86LOxaWKlChk5k6Pa6aHMNqLDR5Aap12KxcbeEazCnmCEC4zlr6sjBuOlfaA4DRBB3L9W0RzpXtlvXSxAJ9VHPisI9s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769428641; c=relaxed/simple; bh=tTnHjqVgFCziCpmvL5ct1YEC2NDheEKPNpZYe4CQ2Y8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AjFQUKd7s1Zot5Gi8LYWvdQBnabydQ+zW7Ms9pEPqXv+e6SnCC1/8QAzbBr9gOxxhAemwpYFOtEi1euOSRStDuHAmWZ81iErosFK7rOIPQwxjgJo+XcnBAjFfbecn+sm2cxeul9IV17Go2P8XFknTziHmiNwSjTCxa45XQGMyIw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EryK8hXu; 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="EryK8hXu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19605C19421; Mon, 26 Jan 2026 11:57:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769428641; bh=tTnHjqVgFCziCpmvL5ct1YEC2NDheEKPNpZYe4CQ2Y8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EryK8hXuTsSx2rChwo89mdblfHtilxoIaAWj4X6gfA9uUj0ix1HFV7N/BKqC+QLxY 5HKV7/WHWkphfEhh1YcLhG3u0X+UM5aj5qWtE9S5QTYJM1YRH9UCX+KsHl6CICD3rM suRsOXEGGyDiI+2BN7UV6lqMj23IrVsgnwb5D2EDU0etPJ7TUEq06iN9tF6o2fXjve ff8z4i+yqYWUN8IeH2hJTljiaIexu02WAfd8ikaaEWSF7mbZ7nypKS3Je2uT6kbAQx rr3bRlm2O6Q4TFdZK98kLO5L20TRV/bFsr4A/u4jDa9V2q3kD/IMCNkMcG1A9A1LrS Sjg3L+6vijUIw== From: Andrey Albershteyn To: fsverity@lists.linux.dev, ebiggers@kernel.org Cc: Andrey Albershteyn , "Darrick J. Wong" Subject: [PATCH v3 1/2] fs: add FS_XFLAG_VERITY for fs-verity files Date: Mon, 26 Jan 2026 12:56:57 +0100 Message-ID: <20260126115658.27656-2-aalbersh@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260126115658.27656-1-aalbersh@kernel.org> References: <20260126115658.27656-1-aalbersh@kernel.org> Precedence: bulk X-Mailing-List: fsverity@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit fs-verity introduced inode flag for inodes with enabled fs-verity on them. This patch adds FS_XFLAG_VERITY file attribute which can be retrieved with FS_IOC_FSGETXATTR ioctl() and file_getattr() syscall. This flag is read-only and can not be set with corresponding set ioctl() and file_setattr(). The FS_IOC_SETFLAGS requires file to be opened for writing which is not allowed for verity files. The FS_IOC_FSSETXATTR and file_setattr() clears this flag from the user input. As this is now common flag for both flag interfaces (flags/xflags) add it to overlapping flags list to exclude it from overwrite. Signed-off-by: Andrey Albershteyn Reviewed-by: "Darrick J. Wong" --- Documentation/filesystems/fsverity.rst | 16 ++++++++++++++++ fs/file_attr.c | 4 ++++ include/linux/fileattr.h | 6 +++--- include/uapi/linux/fs.h | 1 + 4 files changed, 24 insertions(+), 3 deletions(-) diff --git a/Documentation/filesystems/fsverity.rst b/Documentation/filesystems/fsverity.rst index 412cf11e3298..22b49b295d1f 100644 --- a/Documentation/filesystems/fsverity.rst +++ b/Documentation/filesystems/fsverity.rst @@ -341,6 +341,22 @@ the file has fs-verity enabled. This can perform better than FS_IOC_GETFLAGS and FS_IOC_MEASURE_VERITY because it doesn't require opening the file, and opening verity files can be expensive. +FS_IOC_FSGETXATTR +----------------- + +Since Linux v7.0, the FS_IOC_FSGETXATTR ioctl sets FS_XFLAG_VERITY (0x00020000) +in the returned flags when the file has verity enabled. Note that this attribute +cannot be set with FS_IOC_FSSETXATTR as enabling verity requires input +parameters. See FS_IOC_ENABLE_VERITY. + +file_getattr +------------ + +Since Linux v7.0, the file_getattr() syscall sets FS_XFLAG_VERITY (0x00020000) +in the returned flags when the file has verity enabled. Note that this attribute +cannot be set with file_setattr() as enabling verity requires input parameters. +See FS_IOC_ENABLE_VERITY. + .. _accessing_verity_files: Accessing verity files diff --git a/fs/file_attr.c b/fs/file_attr.c index bed5442fa6fa..53b356dd8c33 100644 --- a/fs/file_attr.c +++ b/fs/file_attr.c @@ -37,6 +37,8 @@ void fileattr_fill_xflags(struct file_kattr *fa, u32 xflags) fa->flags |= FS_DAX_FL; if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT) fa->flags |= FS_PROJINHERIT_FL; + if (fa->fsx_xflags & FS_XFLAG_VERITY) + fa->flags |= FS_VERITY_FL; } EXPORT_SYMBOL(fileattr_fill_xflags); @@ -67,6 +69,8 @@ void fileattr_fill_flags(struct file_kattr *fa, u32 flags) fa->fsx_xflags |= FS_XFLAG_DAX; if (fa->flags & FS_PROJINHERIT_FL) fa->fsx_xflags |= FS_XFLAG_PROJINHERIT; + if (fa->flags & FS_VERITY_FL) + fa->fsx_xflags |= FS_XFLAG_VERITY; } EXPORT_SYMBOL(fileattr_fill_flags); diff --git a/include/linux/fileattr.h b/include/linux/fileattr.h index f89dcfad3f8f..3780904a63a6 100644 --- a/include/linux/fileattr.h +++ b/include/linux/fileattr.h @@ -7,16 +7,16 @@ #define FS_COMMON_FL \ (FS_SYNC_FL | FS_IMMUTABLE_FL | FS_APPEND_FL | \ FS_NODUMP_FL | FS_NOATIME_FL | FS_DAX_FL | \ - FS_PROJINHERIT_FL) + FS_PROJINHERIT_FL | FS_VERITY_FL) #define FS_XFLAG_COMMON \ (FS_XFLAG_SYNC | FS_XFLAG_IMMUTABLE | FS_XFLAG_APPEND | \ FS_XFLAG_NODUMP | FS_XFLAG_NOATIME | FS_XFLAG_DAX | \ - FS_XFLAG_PROJINHERIT) + FS_XFLAG_PROJINHERIT | FS_XFLAG_VERITY) /* Read-only inode flags */ #define FS_XFLAG_RDONLY_MASK \ - (FS_XFLAG_PREALLOC | FS_XFLAG_HASATTR) + (FS_XFLAG_PREALLOC | FS_XFLAG_HASATTR | FS_XFLAG_VERITY) /* Flags to indicate valid value of fsx_ fields */ #define FS_XFLAG_VALUES_MASK \ diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h index 66ca526cf786..70b2b661f42c 100644 --- a/include/uapi/linux/fs.h +++ b/include/uapi/linux/fs.h @@ -253,6 +253,7 @@ struct file_attr { #define FS_XFLAG_FILESTREAM 0x00004000 /* use filestream allocator */ #define FS_XFLAG_DAX 0x00008000 /* use DAX for IO */ #define FS_XFLAG_COWEXTSIZE 0x00010000 /* CoW extent size allocator hint */ +#define FS_XFLAG_VERITY 0x00020000 /* fs-verity enabled */ #define FS_XFLAG_HASATTR 0x80000000 /* no DIFLAG for this */ /* the read-only stuff doesn't really belong here, but any other place is -- 2.52.0