From: Andrey Albershteyn Date: Mon, 26 Jan 2026 11:56:57 +0000 (+0100) Subject: fs: add FS_XFLAG_VERITY for fs-verity files X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0e6b7eae1fded85f94a357d6132f07d64c614cfa;p=thirdparty%2Flinux.git fs: add FS_XFLAG_VERITY for fs-verity files 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 Link: https://patch.msgid.link/20260126115658.27656-2-aalbersh@kernel.org Reviewed-by: Darrick J. Wong Signed-off-by: Christian Brauner --- diff --git a/Documentation/filesystems/fsverity.rst b/Documentation/filesystems/fsverity.rst index 412cf11e32985..22b49b295d1f9 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 f3704881c1265..dfde874018171 100644 --- a/fs/file_attr.c +++ b/fs/file_attr.c @@ -36,6 +36,8 @@ 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); @@ -66,6 +68,8 @@ 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 f89dcfad3f8f3..3780904a63a6c 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 66ca526cf786c..70b2b661f42cb 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