On Fri, Jun 7, 2019 at 11:48 AM Jeff Layton <jlayton@xxxxxxxxxx> wrote: > > We have several virtual xattrs in cephfs which return various values as > strings. xattrs don't necessarily return strings however, so we need to > include the terminating NULL byte when we return the length. > > Furthermore, the getxattr manpage says that we should return -ERANGE if > the buffer is too small to hold the resulting value. Let's start doing > that here as well. > > URL: https://bugzilla.redhat.com/show_bug.cgi?id=1717454 > Reported-by: Tomas Petr <tpetr@xxxxxxxxxx> > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> > --- > fs/ceph/xattr.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c > index 6621d27e64f5..2a61e02e7166 100644 > --- a/fs/ceph/xattr.c > +++ b/fs/ceph/xattr.c > @@ -803,8 +803,15 @@ ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value, > if (err) > return err; > err = -ENODATA; > - if (!(vxattr->exists_cb && !vxattr->exists_cb(ci))) > - err = vxattr->getxattr_cb(ci, value, size); > + if (!(vxattr->exists_cb && !vxattr->exists_cb(ci))) { > + /* > + * getxattr_cb returns strlen(value), xattr length must > + * include the NULL. > + */ > + err = vxattr->getxattr_cb(ci, value, size) + 1; > + if (size && size < err) > + err = -ERANGE; > + } > return err; > } Reviewed-by: Patrick Donnelly <pdonnell@xxxxxxxxxx> -- Patrick Donnelly, Ph.D. He / Him / His Senior Software Engineer Red Hat Sunnyvale, CA GPG: 19F28A586F808C2402351B93C3301A3E258DD79D
