On Mon, Apr 17, 2017 at 12:58:02PM -0700, Joe Stringer wrote: > On 14 April 2017 at 20:48, Ben Pfaff <[email protected]> wrote: > > On Wed, Mar 15, 2017 at 04:01:37PM -0700, Joe Stringer wrote: > >> Commit 04f48a68c428 ("ofp-actions: Fix variable length meta-flow OXMs."), > >> on > >> branch-2.7 as 9554b03d6ab7, attempted to address incorrect encode and > >> decode of > >> variable length metaflow fields where the OXM/NXM encoding of the variable > >> length fields would incorrectly serialize the length. The patch addresses > >> this > >> by introducing a new per-bridge structure that adds additional metaflow > >> fields > >> for the variable-length fields on demand when the TLVs are configured by a > >> controller. > >> > >> Unfortunately, in the original patch there was nothing ensuring that flows > >> referring to variable length fields would retain valid field references > >> when > >> controllers reconfigure the TLVs. In practice, this could lead to a crash > >> of > >> ovs-vswitchd by configuring a TLV field, adding a flow which refers to it, > >> removing the TLV field, then running some traffic that hit the configured > >> flow. > >> > >> This series looks to remedy the situation by reference counting the > >> variable > >> length fields and preventing a controller from reconfiguring TLV fields > >> when > >> there are active flows whose match or actions refer to the field. > >> > >> This series was applied to master, but given the size of the change and the > >> minor changes necessary to apply to branch-2.7, I would feel more > >> confident in > >> backporting it if there was an extra round of review to ensure that > >> nothing was > >> missed when this series was first applied to master. > > > > Thanks a lot for backporting this. Backporting is sometimes difficult > > work and rarely rewarding, so I really appreciate seeing it done. > > > > Who should review this? Jarno, I see you made a comment; do you plan to > > review it? > > Hi Ben, > > I think for the library ABI side changes, I would appreciate feedback > from you on how in particular we expect this to be handled (as per my > update to the thread below). > > https://mail.openvswitch.org/pipermail/ovs-dev/2017-March/329954.html > > I spoke to Jarno offline and he mentioned he would be OK reviewing the > code itself. The previous piece of feedback about including another > patch will be addressed by another series which I intend to repost > shortly.
OK. I sent some thoughts in the direction of your longer more detailed message on the subject. _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
