Message ID | 20170517212709.6473-4-vivien.didelot@savoirfairelinux.com |
---|---|
State | Changes Requested, archived |
Delegated to: | David Miller |
Headers | show |
On 5/18/17 12:27 AM, Vivien Didelot wrote: > Be symmetric with br_mdb_add and break if __br_mdb_del returns an error. > > Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> > --- > net/bridge/br_mdb.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c > index d20a01622b20..24eeeefb4179 100644 > --- a/net/bridge/br_mdb.c > +++ b/net/bridge/br_mdb.c > @@ -688,8 +688,9 @@ static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh, > list_for_each_entry(v, &vg->vlan_list, vlist) { > entry->vid = v->vid; > err = __br_mdb_del(br, entry); > - if (!err) > - __br_mdb_notify(dev, p, entry, RTM_DELMDB); > + if (err) > + break; > + __br_mdb_notify(dev, p, entry, RTM_DELMDB); > } > } else { > err = __br_mdb_del(br, entry); > This can potentially break user-space scripts that rely on the best-effort behaviour, this is the normal "delete without vid & enabled vlan filtering". You can check the fdb delete code which does the same, this was intentional. You can add an mdb entry without a vid to all vlans, add a vlan and then try to remove it from all vlans where it is present - with this patch obviously that will fail at the new vlan.
Hi Nikolay, Nikolay Aleksandrov <nikolay@cumulusnetworks.com> writes: >> err = __br_mdb_del(br, entry); >> - if (!err) >> - __br_mdb_notify(dev, p, entry, RTM_DELMDB); >> + if (err) >> + break; >> + __br_mdb_notify(dev, p, entry, RTM_DELMDB); >> } >> } else { >> err = __br_mdb_del(br, entry); >> > > This can potentially break user-space scripts that rely on the best-effort > behaviour, this is the normal "delete without vid & enabled vlan filtering". > You can check the fdb delete code which does the same, this was intentional. > > You can add an mdb entry without a vid to all vlans, add a vlan and then try > to remove it from all vlans where it is present - with this patch obviously > that will fail at the new vlan. OK good to know. That intention wasn't obvious. I can make __br_mdb_del return void instead? What about the rest of the patchset if I do so? Thanks, Vivien
On 5/18/17 6:08 PM, Vivien Didelot wrote: > Hi Nikolay, > > Nikolay Aleksandrov <nikolay@cumulusnetworks.com> writes: > >>> err = __br_mdb_del(br, entry); >>> - if (!err) >>> - __br_mdb_notify(dev, p, entry, RTM_DELMDB); >>> + if (err) >>> + break; >>> + __br_mdb_notify(dev, p, entry, RTM_DELMDB); >>> } >>> } else { >>> err = __br_mdb_del(br, entry); >>> >> >> This can potentially break user-space scripts that rely on the best-effort >> behaviour, this is the normal "delete without vid & enabled vlan filtering". >> You can check the fdb delete code which does the same, this was intentional. >> >> You can add an mdb entry without a vid to all vlans, add a vlan and then try >> to remove it from all vlans where it is present - with this patch obviously >> that will fail at the new vlan. > > OK good to know. That intention wasn't obvious. I can make __br_mdb_del > return void instead? What about the rest of the patchset if I do so? > > Thanks, > > Vivien > If you make it return void we will not be able to return proper error value when doing a single operation (the else case). About the rest I see only some minor style issues, I'll comment on the respective patches. Another minor nit is using switch() instead of if/else for the message types but that is really up to you, I don't mind either way. :-) Cheers, Nik
Hi Nikolay, Nikolay Aleksandrov <nikolay@cumulusnetworks.com> writes: >> OK good to know. That intention wasn't obvious. I can make __br_mdb_del >> return void instead? What about the rest of the patchset if I do so? > > If you make it return void we will not be able to return proper error value > when doing a single operation (the else case). About the rest I see only some > minor style issues, I'll comment on the respective patches. Another minor nit is > using switch() instead of if/else for the message types but that is really up to > you, I don't mind either way. :-) Ho OK I understand better the batch vs single delete operation now. __br_mdb_do hardly makes sense now, because we don't know which case we are handling... But factorizing br_mdb_do still makes sense. I'll come up with something. Thanks, Vivien
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c index d20a01622b20..24eeeefb4179 100644 --- a/net/bridge/br_mdb.c +++ b/net/bridge/br_mdb.c @@ -688,8 +688,9 @@ static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh, list_for_each_entry(v, &vg->vlan_list, vlist) { entry->vid = v->vid; err = __br_mdb_del(br, entry); - if (!err) - __br_mdb_notify(dev, p, entry, RTM_DELMDB); + if (err) + break; + __br_mdb_notify(dev, p, entry, RTM_DELMDB); } } else { err = __br_mdb_del(br, entry);
Be symmetric with br_mdb_add and break if __br_mdb_del returns an error. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> --- net/bridge/br_mdb.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)