[Bionic/Cosmic/Disco/Unstable][SRU][PATCH 1/1] UBUNTU: SAUCE: openvswitch: Disable eventmask support on 32-bit

[Juerg Haefliger]

BugLink: https://bugs.launchpad.net/bugs/1736390

Openvswitch eventmask support for CT actions was introduced with commit
120645513f55 ("openvswitch: Add eventmask support to CT action."). This
commit introduces a regression on i386 which results in a kernel crash.
Fix that by disabling eventmask support on i386.

Per upstream, the result of *not* having this "will cause additional CPU
use and potential buffering issues for CT event monitors in userspace."

https://lore.kernel.org/lkml/E891AED6-8406-4914-BDC3-92248F77C63B@ovn.org/

Fixes: 120645513f55 ("openvswitch: Add eventmask support to CT action.")
Signed-off-by: Juerg Haefliger <juergh at canonical.com>
---
 include/uapi/linux/openvswitch.h |  2 ++
 net/openvswitch/conntrack.c      | 12 ++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index dcfab5e3b55c..9da2942d7f7e 100644
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -744,7 +744,9 @@ enum ovs_ct_attr {
 				   related connections. */
 	OVS_CT_ATTR_NAT,        /* Nested OVS_NAT_ATTR_* */
 	OVS_CT_ATTR_FORCE_COMMIT,  /* No argument */
+#ifndef CONFIG_X86_32
 	OVS_CT_ATTR_EVENTMASK,  /* u32 mask of IPCT_* events. */
+#endif
 	__OVS_CT_ATTR_MAX
 };
 
diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index 8f04bd6e44bb..0c44fb56317e 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -66,9 +66,13 @@ struct ovs_conntrack_info {
 	u8 commit : 1;
 	u8 nat : 3;                 /* enum ovs_ct_nat */
 	u8 force : 1;
+#ifndef CONFIG_X86_32
 	u8 have_eventmask : 1;
+#endif
 	u16 family;
+#ifndef CONFIG_X86_32
 	u32 eventmask;              /* Mask of 1 << IPCT_*. */
+#endif
 	struct md_mark mark;
 	struct md_labels labels;
 #ifdef CONFIG_NF_NAT_NEEDED
@@ -1054,6 +1058,7 @@ static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
 	if (!ct)
 		return 0;
 
+#ifndef CONFIG_X86_32
 	/* Set the conntrack event mask if given.  NEW and DELETE events have
 	 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener
 	 * typically would receive many kinds of updates.  Setting the event
@@ -1067,6 +1072,7 @@ static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
 		if (cache)
 			cache->ctmask = info->eventmask;
 	}
+#endif
 
 	/* Apply changes before confirming the connection so that the initial
 	 * conntrack NEW netlink event carries the values given in the CT
@@ -1340,8 +1346,10 @@ static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
 	/* NAT length is checked when parsing the nested attributes. */
 	[OVS_CT_ATTR_NAT]	= { .minlen = 0, .maxlen = INT_MAX },
 #endif
+#ifndef CONFIG_X86_32
 	[OVS_CT_ATTR_EVENTMASK]	= { .minlen = sizeof(u32),
 				    .maxlen = sizeof(u32) },
+#endif
 };
 
 static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
@@ -1423,10 +1431,12 @@ static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
 			break;
 		}
 #endif
+#ifndef CONFIG_X86_32
 		case OVS_CT_ATTR_EVENTMASK:
 			info->have_eventmask = true;
 			info->eventmask = nla_get_u32(a);
 			break;
+#endif
 
 		default:
 			OVS_NLERR(log, "Unknown conntrack attr (%d)",
@@ -1627,9 +1637,11 @@ int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
 				   ct_info->helper->name))
 			return -EMSGSIZE;
 	}
+#ifndef CONFIG_X86_32
 	if (ct_info->have_eventmask &&
 	    nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask))
 		return -EMSGSIZE;
+#endif
 
 #ifdef CONFIG_NF_NAT_NEEDED
 	if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
-- 
2.19.1