From b9d80714583bf40e354ad0fc364ebfb35a0b3d76 Mon Sep 17 00:00:00 2001 From: Thomas Haller Date: Thu, 20 Dec 2018 13:05:13 +0100 Subject: dhcp: fix sd_dhcp_client_set_client_id() for infiniband addresses Infiniband addresses are 20 bytes (INFINIBAND_ALEN), but only the last 8 bytes are suitable for putting into the client-id. This bug had no effect for networkd, because sd_dhcp_client_set_client_id() has only one caller which always uses ARPHRD_ETHER type. I was unable to find good references for why this is correct ([1]). Fedora/RHEL has patches for ISC dhclient that also only use the last 8 bytes ([2], [3]). RFC 4390 (Dynamic Host Configuration Protocol (DHCP) over InfiniBand) [4] does not discuss the content of the client-id either. [1] https://bugzilla.redhat.com/show_bug.cgi?id=1658057#c29 [2] https://bugzilla.redhat.com/show_bug.cgi?id=660681 [3] https://src.fedoraproject.org/rpms/dhcp/blob/3ccf3c8d815df4b8e11e1a04850975f099273d5d/f/dhcp-lpf-ib.patch [4] https://tools.ietf.org/html/rfc4390 --- src/libsystemd-network/sd-dhcp-client.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c index 3bdd584bb..ff7f54793 100644 --- a/src/libsystemd-network/sd-dhcp-client.c +++ b/src/libsystemd-network/sd-dhcp-client.c @@ -308,7 +308,9 @@ int sd_dhcp_client_set_client_id( break; case ARPHRD_INFINIBAND: - if (data_len != INFINIBAND_ALEN) + /* Infiniband addresses are 20 bytes (INFINIBAND_ALEN), however only + * the last 8 bytes are stable and suitable for putting into the client-id. */ + if (data_len != 8) return -EINVAL; break; -- cgit v1.2.3-65-gdbad