The fattr->fa_xflags is a u64 that comes from the user. This is a sanity
check to ensure that the users are only setting allowed flags. The
problem is that it doesn't check the upper 32 bits. It doesn't really
affect anything but for more flexibility in the future, we want to enforce
users zero out those bits.
Fixes: be7efb2d20 ("fs: introduce file_getattr and file_setattr syscalls")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/baf7b808-bcf2-4ac1-9313-882c91cc87b2@sabinyo.mountain
Signed-off-by: Christian Brauner <brauner@kernel.org>
Introduce file_getattr() and file_setattr() syscalls to manipulate inode
extended attributes. The syscalls takes pair of file descriptor and
pathname. Then it operates on inode opened accroding to openat()
semantics. The struct file_attr is passed to obtain/change extended
attributes.
This is an alternative to FS_IOC_FSSETXATTR ioctl with a difference
that file don't need to be open as we can reference it with a path
instead of fd. By having this we can manipulated inode extended
attributes not only on regular files but also on special ones. This
is not possible with FS_IOC_FSSETXATTR ioctl as with special files
we can not call ioctl() directly on the filesystem inode using fd.
This patch adds two new syscalls which allows userspace to get/set
extended inode attributes on special files by using parent directory
and a path - *at() like syscall.
CC: linux-api@vger.kernel.org
CC: linux-fsdevel@vger.kernel.org
CC: linux-xfs@vger.kernel.org
Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org>
Link: https://lore.kernel.org/20250630-xattrat-syscall-v6-6-c4e3bc35227b@kernel.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Future patches will add new syscalls which use these functions. As
this interface won't be used for ioctls only, the EOPNOSUPP is more
appropriate return code.
This patch converts return code from ENOIOCTLCMD to EOPNOSUPP for
vfs_fileattr_get and vfs_fileattr_set. To save old behavior translate
EOPNOSUPP back for current users - overlayfs, encryptfs and fs/ioctl.c.
Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org>
Link: https://lore.kernel.org/20250630-xattrat-syscall-v6-4-c4e3bc35227b@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
