On Mon, Jun 20, 2022 at 08:38:36PM -0500, Eric Sandeen wrote:
> We got a report that "renameat2() with flags=RENAME_WHITEOUT doesn't
> apply an SELinux label on xfs" as it does on other filesystems
> (for example, ext4 and tmpfs.) While I'm not quite sure how labels
> may interact w/ whiteout files, leaving them as unlabeled seems
> inconsistent at best. Now that xfs_init_security is not static,
> rename it to xfs_inode_init_security per dchinner's suggestion.
>
> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
> Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx>
Looks fine to me. I wondered slightly if the label creation needs to be
atomic with the file creation, but quickly realized that /never/
happens. Assuming this isn't high priority 5.19 stuff, I'll just roll
this into 5.20 if that's ok?
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
--D
> ---
> fs/xfs/xfs_inode.c | 14 +++++++++++++-
> fs/xfs/xfs_iops.c | 11 +++++------
> fs/xfs/xfs_iops.h | 3 +++
> 3 files changed, 21 insertions(+), 7 deletions(-)
>
> diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
> index 52d6f2c..58513a1 100644
> --- a/fs/xfs/xfs_inode.c
> +++ b/fs/xfs/xfs_inode.c
> @@ -3046,10 +3046,12 @@ struct xfs_iunlink {
> static int
> xfs_rename_alloc_whiteout(
> struct user_namespace *mnt_userns,
> + struct xfs_name *src_name,
> struct xfs_inode *dp,
> struct xfs_inode **wip)
> {
> struct xfs_inode *tmpfile;
> + struct qstr name;
> int error;
>
> error = xfs_create_tmpfile(mnt_userns, dp, S_IFCHR | WHITEOUT_MODE,
> @@ -3057,6 +3059,15 @@ struct xfs_iunlink {
> if (error)
> return error;
>
> + name.name = src_name->name;
> + name.len = src_name->len;
> + error = xfs_inode_init_security(VFS_I(tmpfile), VFS_I(dp), &name);
> + if (error) {
> + xfs_finish_inode_setup(tmpfile);
> + xfs_irele(tmpfile);
> + return error;
> + }
> +
> /*
> * Prepare the tmpfile inode as if it were created through the VFS.
> * Complete the inode setup and flag it as linkable. nlink is already
> @@ -3107,7 +3118,8 @@ struct xfs_iunlink {
> * appropriately.
> */
> if (flags & RENAME_WHITEOUT) {
> - error = xfs_rename_alloc_whiteout(mnt_userns, target_dp, &wip);
> + error = xfs_rename_alloc_whiteout(mnt_userns, src_name,
> + target_dp, &wip);
> if (error)
> return error;
>
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index 29f5b8b8..6720b60 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -75,9 +75,8 @@
> * these attrs can be journalled at inode creation time (along with the
> * inode, of course, such that log replay can't cause these to be lost).
> */
> -
> -STATIC int
> -xfs_init_security(
> +int
> +xfs_inode_init_security(
> struct inode *inode,
> struct inode *dir,
> const struct qstr *qstr)
> @@ -122,7 +121,7 @@
>
> /* Oh, the horror.
> * If we can't add the ACL or we fail in
> - * xfs_init_security we must back out.
> + * xfs_inode_init_security we must back out.
> * ENOSPC can hit here, among other things.
> */
> xfs_dentry_to_name(&teardown, dentry);
> @@ -208,7 +207,7 @@
>
> inode = VFS_I(ip);
>
> - error = xfs_init_security(inode, dir, &dentry->d_name);
> + error = xfs_inode_init_security(inode, dir, &dentry->d_name);
> if (unlikely(error))
> goto out_cleanup_inode;
>
> @@ -424,7 +423,7 @@
>
> inode = VFS_I(cip);
>
> - error = xfs_init_security(inode, dir, &dentry->d_name);
> + error = xfs_inode_init_security(inode, dir, &dentry->d_name);
> if (unlikely(error))
> goto out_cleanup_inode;
>
> diff --git a/fs/xfs/xfs_iops.h b/fs/xfs/xfs_iops.h
> index 2789490..cb5fc68 100644
> --- a/fs/xfs/xfs_iops.h
> +++ b/fs/xfs/xfs_iops.h
> @@ -17,4 +17,7 @@
> int xfs_vn_setattr_size(struct user_namespace *mnt_userns,
> struct dentry *dentry, struct iattr *vap);
>
> +int xfs_inode_init_security(struct inode *inode, struct inode *dir,
> + const struct qstr *qstr);
> +
> #endif /* __XFS_IOPS_H__ */
> --
> 1.8.3.1
>
