Merge tag 'net-6.5-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Paolo Abeni:
 "Including fixes from wifi, can and netfilter.

  Fixes to fixes:

   - nf_tables:
       - GC transaction race with abort path
       - defer gc run if previous batch is still pending

  Previous releases - regressions:

   - ipv4: fix data-races around inet->inet_id

   - phy: fix deadlocking in phy_error() invocation

   - mdio: fix C45 read/write protocol

   - ipvlan: fix a reference count leak warning in ipvlan_ns_exit()

   - ice: fix NULL pointer deref during VF reset

   - i40e: fix potential NULL pointer dereferencing of pf->vf in
     i40e_sync_vsi_filters()

   - tg3: use slab_build_skb() when needed

   - mtk_eth_soc: fix NULL pointer on hw reset

  Previous releases - always broken:

   - core: validate veth and vxcan peer ifindexes

   - sched: fix a qdisc modification with ambiguous command request

   - devlink: add missing unregister linecard notification

   - wifi: mac80211: limit reorder_buf_filtered to avoid UBSAN warning

   - batman:
      - do not get eth header before batadv_check_management_packet
      - fix batadv_v_ogm_aggr_send memory leak

   - bonding: fix macvlan over alb bond support

   - mlxsw: set time stamp fields also when its type is MIRROR_UTC"

* tag 'net-6.5-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (54 commits)
  selftests: bonding: add macvlan over bond testing
  selftest: bond: add new topo bond_topo_2d1c.sh
  bonding: fix macvlan over alb bond support
  rtnetlink: Reject negative ifindexes in RTM_NEWLINK
  netfilter: nf_tables: defer gc run if previous batch is still pending
  netfilter: nf_tables: fix out of memory error handling
  netfilter: nf_tables: use correct lock to protect gc_list
  netfilter: nf_tables: GC transaction race with abort path
  netfilter: nf_tables: flush pending destroy work before netlink notifier
  netfilter: nf_tables: validate all pending tables
  ibmveth: Use dcbf rather than dcbfl
  i40e: fix potential NULL pointer dereferencing of pf->vf i40e_sync_vsi_filters()
  net/sched: fix a qdisc modification with ambiguous command request
  igc: Fix the typo in the PTM Control macro
  batman-adv: Hold rtnl lock during MTU update via netlink
  igb: Avoid starting unnecessary workqueues
  can: raw: add missing refcount for memory leak fix
  can: isotp: fix support for transmission of SF without flow control
  bnx2x: new flag for track HW resource allocation
  sfc: allocate a big enough SKB for loopback selftest packet
  ...

1 files changed, 40 insertions, 13 deletions

diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index aa6b1fe65151..e9eaf637220e 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1547,10 +1547,28 @@ static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
 	return 0;
 }
 
+static bool req_create_or_replace(struct nlmsghdr *n)
+{
+	return (n->nlmsg_flags & NLM_F_CREATE &&
+		n->nlmsg_flags & NLM_F_REPLACE);
+}
+
+static bool req_create_exclusive(struct nlmsghdr *n)
+{
+	return (n->nlmsg_flags & NLM_F_CREATE &&
+		n->nlmsg_flags & NLM_F_EXCL);
+}
+
+static bool req_change(struct nlmsghdr *n)
+{
+	return (!(n->nlmsg_flags & NLM_F_CREATE) &&
+		!(n->nlmsg_flags & NLM_F_REPLACE) &&
+		!(n->nlmsg_flags & NLM_F_EXCL));
+}
+
 /*
  * Create/change qdisc.
  */
-
 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
 			   struct netlink_ext_ack *extack)
 {
@@ -1644,27 +1662,35 @@ replay:
 				 *
 				 *   We know, that some child q is already
 				 *   attached to this parent and have choice:
-				 *   either to change it or to create/graft new one.
+				 *   1) change it or 2) create/graft new one.
+				 *   If the requested qdisc kind is different
+				 *   than the existing one, then we choose graft.
+				 *   If they are the same then this is "change"
+				 *   operation - just let it fallthrough..
 				 *
 				 *   1. We are allowed to create/graft only
-				 *   if CREATE and REPLACE flags are set.
+				 *   if the request is explicitly stating
+				 *   "please create if it doesn't exist".
 				 *
-				 *   2. If EXCL is set, requestor wanted to say,
-				 *   that qdisc tcm_handle is not expected
+				 *   2. If the request is to exclusive create
+				 *   then the qdisc tcm_handle is not expected
 				 *   to exist, so that we choose create/graft too.
 				 *
 				 *   3. The last case is when no flags are set.
+				 *   This will happen when for example tc
+				 *   utility issues a "change" command.
 				 *   Alas, it is sort of hole in API, we
 				 *   cannot decide what to do unambiguously.
-				 *   For now we select create/graft, if
-				 *   user gave KIND, which does not match existing.
+				 *   For now we select create/graft.
 				 */
-				if ((n->nlmsg_flags & NLM_F_CREATE) &&
-				    (n->nlmsg_flags & NLM_F_REPLACE) &&
-				    ((n->nlmsg_flags & NLM_F_EXCL) ||
-				     (tca[TCA_KIND] &&
-				      nla_strcmp(tca[TCA_KIND], q->ops->id))))
-					goto create_n_graft;
+				if (tca[TCA_KIND] &&
+				    nla_strcmp(tca[TCA_KIND], q->ops->id)) {
+					if (req_create_or_replace(n) ||
+					    req_create_exclusive(n))
+						goto create_n_graft;
+					else if (req_change(n))
+						goto create_n_graft2;
+				}
 			}
 		}
 	} else {
@@ -1698,6 +1724,7 @@ create_n_graft:
 		NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag");
 		return -ENOENT;
 	}
+create_n_graft2:
 	if (clid == TC_H_INGRESS) {
 		if (dev_ingress_queue(dev)) {
 			q = qdisc_create(dev, dev_ingress_queue(dev),