From cbada1048847a348797aec63a1d8056621cbe653 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Tue, 10 Mar 2026 22:59:16 +0100 Subject: neighbour: restore protocol != 0 check in pneigh update Prior to commit dc2a27e524ac ("neighbour: Update pneigh_entry in pneigh_create()."), a pneigh's protocol was updated only when the value of the NDA_PROTOCOL attribute was non-0. While moving the code, that check was removed. This is a small change of user-visible behavior, and inconsistent with the (non-proxy) neighbour behavior. Fixes: dc2a27e524ac ("neighbour: Update pneigh_entry in pneigh_create().") Signed-off-by: Sabrina Dubroca Reviewed-by: David Ahern Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/38c61de1bb032871a886aff9b9b52fe1cdd4cada.1772894876.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski --- net/core/neighbour.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/core/neighbour.c b/net/core/neighbour.c index a95cfe77f7f0..c56a4e7bf790 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -820,7 +820,8 @@ int pneigh_create(struct neigh_table *tbl, struct net *net, update: WRITE_ONCE(n->flags, flags); n->permanent = permanent; - WRITE_ONCE(n->protocol, protocol); + if (protocol) + WRITE_ONCE(n->protocol, protocol); out: mutex_unlock(&tbl->phash_lock); return err; -- cgit v1.2.3 From 68e76fc12df091b04ede5f6244385a35abae0a80 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Tue, 10 Mar 2026 22:59:17 +0100 Subject: selftests: rtnetlink: add neighbour update test Check that protocol and flags are updated correctly for neighbour and pneigh entries. Signed-off-by: Sabrina Dubroca Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/d28f72b5b4ff4c9ecbbbde06146a938dcc4c264a.1772894876.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski --- tools/testing/selftests/net/rtnetlink.sh | 55 ++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/tools/testing/selftests/net/rtnetlink.sh b/tools/testing/selftests/net/rtnetlink.sh index 248c2b91fe42..5a5ff88321d5 100755 --- a/tools/testing/selftests/net/rtnetlink.sh +++ b/tools/testing/selftests/net/rtnetlink.sh @@ -28,6 +28,7 @@ ALL_TESTS=" kci_test_fdb_get kci_test_fdb_del kci_test_neigh_get + kci_test_neigh_update kci_test_bridge_parent_id kci_test_address_proto kci_test_enslave_bonding @@ -1160,6 +1161,60 @@ kci_test_neigh_get() end_test "PASS: neigh get" } +kci_test_neigh_update() +{ + dstip=10.0.2.4 + dstmac=de:ad:be:ef:13:37 + local ret=0 + + for proxy in "" "proxy" ; do + # add a neighbour entry without any flags + run_cmd ip neigh add $proxy $dstip dev "$devdummy" lladdr $dstmac nud permanent + run_cmd_grep $dstip ip neigh show $proxy + run_cmd_grep_fail "$dstip dev $devdummy .*\(managed\|use\|router\|extern\)" ip neigh show $proxy + + # set the extern_learn flag, but no other + run_cmd ip neigh change $proxy $dstip dev "$devdummy" extern_learn + run_cmd_grep "$dstip dev $devdummy .* extern_learn" ip neigh show $proxy + run_cmd_grep_fail "$dstip dev $devdummy .* \(managed\|use\|router\)" ip neigh show $proxy + + # flags are reset when not provided + run_cmd ip neigh change $proxy $dstip dev "$devdummy" + run_cmd_grep $dstip ip neigh show $proxy + run_cmd_grep_fail "$dstip dev $devdummy .* extern_learn" ip neigh show $proxy + + # add a protocol + run_cmd ip neigh change $proxy $dstip dev "$devdummy" protocol boot + run_cmd_grep "$dstip dev $devdummy .* proto boot" ip neigh show $proxy + + # protocol is retained when not provided + run_cmd ip neigh change $proxy $dstip dev "$devdummy" + run_cmd_grep "$dstip dev $devdummy .* proto boot" ip neigh show $proxy + + # change protocol + run_cmd ip neigh change $proxy $dstip dev "$devdummy" protocol static + run_cmd_grep "$dstip dev $devdummy .* proto static" ip neigh show $proxy + + # also check an extended flag for non-proxy neighs + if [ "$proxy" = "" ]; then + run_cmd ip neigh change $proxy $dstip dev "$devdummy" managed + run_cmd_grep "$dstip dev $devdummy managed" ip neigh show $proxy + + run_cmd ip neigh change $proxy $dstip dev "$devdummy" lladdr $dstmac + run_cmd_grep_fail "$dstip dev $devdummy managed" ip neigh show $proxy + fi + + run_cmd ip neigh del $proxy $dstip dev "$devdummy" + done + + if [ $ret -ne 0 ];then + end_test "FAIL: neigh update" + return 1 + fi + + end_test "PASS: neigh update" +} + kci_test_bridge_parent_id() { local ret=0 -- cgit v1.2.3