Re: [PATCH 2/5] vfs: create a generic checking function for FS_IOC_FSSETXATTR
From: Al Viro <viro@zeniv.linux.org.uk>
Date: 2019-06-26 04:12:29
Also in:
linux-btrfs, linux-efi, linux-f2fs-devel, linux-fsdevel, linux-xfs, lkml, ocfs2-devel
On Tue, Jun 25, 2019 at 07:32:18PM -0700, Darrick J. Wong wrote:
quoted hunk ↗ jump to hunk
--- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c@@ -373,10 +373,9 @@ static int check_xflags(unsigned int flags) static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg) { struct btrfs_inode *binode = BTRFS_I(file_inode(file)); - struct fsxattr fa; - - memset(&fa, 0, sizeof(fa)); - fa.fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags); + struct fsxattr fa = { + .fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags), + };
Umm... Sure, there's no padding, but still - you are going to copy that thing
to userland... How about
static inline void simple_fill_fsxattr(struct fsxattr *fa, unsigned xflags)
{
memset(fa, 0, sizeof(*fa));
fa->fsx_xflags = xflags;
}
and let the compiler optimize the crap out?