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    SubjectRe: [PATCH 1/2] ecryptfs: fix uid translation for setxattr on security.capability
    Miklos Szeredi <mszeredi@redhat.com> writes:

    > Prior to commit 7c03e2cda4a5 ("vfs: move cap_convert_nscap() call into
    > vfs_setxattr()") the translation of nscap->rootid did not take stacked
    > filesystems (overlayfs and ecryptfs) into account.
    >
    > That patch fixed the overlay case, but made the ecryptfs case worse.
    >
    > Restore old the behavior for ecryptfs that existed before the overlayfs
    > fix. This does not fix ecryptfs's handling of complex user namespace
    > setups, but it does make sure existing setups don't regress.

    Today vfs_setxattr handles handles a delegated_inode and breaking
    leases. Code that is enabled with CONFIG_FILE_LOCKING. So unless
    I am missing something this introduces a different regression into
    ecryptfs.

    >
    > Reported-by: Eric W. Biederman <ebiederm@xmission.com>
    > Cc: Tyler Hicks <code@tyhicks.com>
    > Fixes: 7c03e2cda4a5 ("vfs: move cap_convert_nscap() call into vfs_setxattr()")
    > Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
    > ---
    > fs/ecryptfs/inode.c | 10 +++++++---
    > 1 file changed, 7 insertions(+), 3 deletions(-)
    >
    > diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
    > index e23752d9a79f..58d0f7187997 100644
    > --- a/fs/ecryptfs/inode.c
    > +++ b/fs/ecryptfs/inode.c
    > @@ -1016,15 +1016,19 @@ ecryptfs_setxattr(struct dentry *dentry, struct inode *inode,
    > {
    > int rc;
    > struct dentry *lower_dentry;
    > + struct inode *lower_inode;
    >
    > lower_dentry = ecryptfs_dentry_to_lower(dentry);
    > - if (!(d_inode(lower_dentry)->i_opflags & IOP_XATTR)) {
    > + lower_inode = d_inode(lower_dentry);
    > + if (!(lower_inode->i_opflags & IOP_XATTR)) {
    > rc = -EOPNOTSUPP;
    > goto out;
    > }
    > - rc = vfs_setxattr(lower_dentry, name, value, size, flags);
    > + inode_lock(lower_inode);
    > + rc = __vfs_setxattr_locked(lower_dentry, name, value, size, flags, NULL);
    > + inode_unlock(lower_inode);
    > if (!rc && inode)
    > - fsstack_copy_attr_all(inode, d_inode(lower_dentry));
    > + fsstack_copy_attr_all(inode, lower_inode);
    > out:
    > return rc;
    > }

    Eric

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