On Wed, Sep 29, 2021 at 09:00:56AM +0200, Jack Wang wrote: > Leon Romanovsky <leon@xxxxxxxxxx> 于2021年9月28日周二 上午9:28写道： > > > > On Tue, Sep 28, 2021 at 09:08:26AM +0200, Jack Wang wrote: > > > Leon Romanovsky <leon@xxxxxxxxxx> 于2021年9月27日周一 下午2:23写道： > > > > > > > > On Wed, Sep 22, 2021 at 02:53:32PM +0200, Md Haris Iqbal wrote: > > > > > Allowing these characters in sessname can lead to unexpected results, > > > > > particularly because / is used as a separator between files in a path, > > > > > and . points to the current directory. > > > > > > > > > > Signed-off-by: Md Haris Iqbal <haris.iqbal@xxxxxxxxx> > > > > > Reviewed-by: Gioh Kim <gi-oh.kim@xxxxxxxxx> > > > > > Reviewed-by: Aleksei Marov <aleksei.marov@xxxxxxxxx> > > > > > --- > > > > > drivers/infiniband/ulp/rtrs/rtrs-clt.c | 6 ++++++ > > > > > drivers/infiniband/ulp/rtrs/rtrs-srv.c | 5 +++++ > > > > > 2 files changed, 11 insertions(+) > > > > > > > > It will be safer if you check for only allowed symbols and disallow > > > > everything else. Check for: a-Z, 0-9 and "-". > > > > > > > Hi Leon, > > > > > > Thanks for your suggestions. > > > The reasons we choose to do disallow only '/' and '.': > > > 1 more flexible, most UNIX filenames allow any 8-bit set, except '/' and null. > > > > So you need to add all possible protections and checks that VFS has to allow "random" name. > It's only about sysfs here, as we use sessname to create dir in sysfs, > and I checked the code, it allows any 8-bit set, and convert '/' to > '!', see https://elixir.bootlin.com/linux/latest/source/lib/kobject.c#L299 > > > > > 2 matching for 2 characters is faster than checking all the allowed > > > symbols during session establishment. > > > > Extra CPU cycles won't make any difference here. > As we can have hundreds of sessions, in the end, it matters. Your rtrs_clt_open() function is far from being optimized for performance. It allocates memory, iterates over all paths, creates sysfs and kobject. So no, it doesn't matter here. Thanks > > Thanks > > > > > 3 we do use hostnameA@hostnameB for production usage right now, we > > > don't want to break the user space. > > > > You can add "@" into the list of accepted symbols. > > > > > > > > I hope this makes sense to you. > > > > > > Regards! > > > > > > > > > > > > > > > > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c > > > > > index bc8824b4ee0d..15c0077dd27e 100644 > > > > > --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c > > > > > +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c > > > > > @@ -2788,6 +2788,12 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops, > > > > > struct rtrs_clt *clt; > > > > > int err, i; > > > > > > > > > > + if (strchr(sessname, '/') || strchr(sessname, '.')) { > > > > > + pr_err("sessname cannot contain / and .\n"); > > > > > + err = -EINVAL; > > > > > + goto out; > > > > > + } > > > > > + > > > > > clt = alloc_clt(sessname, paths_num, port, pdu_sz, ops->priv, > > > > > ops->link_ev, > > > > > reconnect_delay_sec, > > > > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c > > > > > index 078a1cbac90c..7df71f8cf149 100644 > > > > > --- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c > > > > > +++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c > > > > > @@ -803,6 +803,11 @@ static int process_info_req(struct rtrs_srv_con *con, > > > > > return err; > > > > > } > > > > > > > > > > + if (strchr(msg->sessname, '/') || strchr(msg->sessname, '.')) { > > > > > + rtrs_err(s, "sessname cannot contain / and .\n"); > > > > > + return -EINVAL; > > > > > + } > > > > > + > > > > > if (exist_sessname(sess->srv->ctx, > > > > > msg->sessname, &sess->srv->paths_uuid)) { > > > > > rtrs_err(s, "sessname is duplicated: %s\n", msg->sessname); > > > > > -- > > > > > 2.25.1 > > > > >
