diff mbox series

[RFC,net-next,02/10] net: bridge: Always multicast_flood Reports

Message ID 20240402001137.2980589-3-Joseph.Huang@garmin.com (mailing list archive)
State RFC
Delegated to: Netdev Maintainers
Headers show
Series MC Flood disable and snooping | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 950 this patch: 950
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang success Errors and warnings before: 955 this patch: 955
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes fail Problems with Fixes tag: 1
netdev/build_allmodconfig_warn success Errors and warnings before: 961 this patch: 961
netdev/checkpatch warning WARNING: line length of 88 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 1 this patch: 1
netdev/source_inline success Was 0 now: 0

Commit Message

Joseph Huang April 2, 2024, 12:11 a.m. UTC 
Modify the forwarding path so that IGMPv1/v2/MLDv1 Reports are always
flooded by br_multicast_flood(), regardless of the check done
by br_multicast_querier_exists().

This patch fixes the problems where shortly after a system boots up,
the first couple of Reports are not handled properly in that:

1) The Report from the Host is being flooded (via br_flood) to all
   bridge ports, and
2) If the mrouter port's multicast flooding is disabled, the Reports
   received from other hosts will not be forwarded to the Querier.

Fixes: b00589af3b04 ("bridge: disable snooping if there is no querier")

Signed-off-by: Joseph Huang <Joseph.Huang@garmin.com>
---
 net/bridge/br_device.c    | 5 +++--
 net/bridge/br_input.c     | 5 +++--
 net/bridge/br_multicast.c | 5 +++++
 net/bridge/br_private.h   | 3 +++
 4 files changed, 14 insertions(+), 4 deletions(-)

Comments

Simon Horman April 3, 2024, 3:52 p.m. UTC | #1 
On Mon, Apr 01, 2024 at 08:11:01PM -0400, Joseph Huang wrote:
> Modify the forwarding path so that IGMPv1/v2/MLDv1 Reports are always
> flooded by br_multicast_flood(), regardless of the check done
> by br_multicast_querier_exists().
> 
> This patch fixes the problems where shortly after a system boots up,
> the first couple of Reports are not handled properly in that:
> 
> 1) The Report from the Host is being flooded (via br_flood) to all
>    bridge ports, and
> 2) If the mrouter port's multicast flooding is disabled, the Reports
>    received from other hosts will not be forwarded to the Querier.
> 
> Fixes: b00589af3b04 ("bridge: disable snooping if there is no querier")
> 

There should be no blank line between Fixes and other tags.

If this is a fix, it should be targeted against net,
and likely broken out of this series.

If it is not a fix, then it should not have a Fixes tag.
Rather, you can reference a commit in the commit message text
(not tags) using something like.

Introduced by commit b00589af3b04 ("bridge: disable snooping if there is no querier")

Link: https://www.kernel.org/doc/html/next/process/maintainer-netdev.html

> Signed-off-by: Joseph Huang <Joseph.Huang@garmin.com>

...
diff mbox series

Patch

diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index c366ccc8b3db..5c09b9dd61dc 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -93,8 +93,9 @@  netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 		}
 
 		mdst = br_mdb_entry_skb_get(brmctx, skb, vid);
-		if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
-		    br_multicast_querier_exists(brmctx, eth_hdr(skb), mdst))
+		if (((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
+		     br_multicast_querier_exists(brmctx, eth_hdr(skb), mdst)) ||
+		    BR_INPUT_SKB_CB_FORCE_MC_FLOOD(skb))
 			br_multicast_flood(mdst, skb, brmctx, false, true);
 		else
 			br_flood(br, skb, BR_PKT_MULTICAST, false, true, vid);
diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index f21097e73482..8e614ab20966 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -176,8 +176,9 @@  int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
 	switch (pkt_type) {
 	case BR_PKT_MULTICAST:
 		mdst = br_mdb_entry_skb_get(brmctx, skb, vid);
-		if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
-		    br_multicast_querier_exists(brmctx, eth_hdr(skb), mdst)) {
+		if (((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
+		     br_multicast_querier_exists(brmctx, eth_hdr(skb), mdst)) ||
+		    BR_INPUT_SKB_CB_FORCE_MC_FLOOD(skb)) {
 			if ((mdst && mdst->host_joined) ||
 			    br_multicast_is_router(brmctx, skb)) {
 				local_rcv = true;
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 42d900549227..8531f0e03f41 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -3844,6 +3844,7 @@  static int br_multicast_ipv4_rcv(struct net_bridge_mcast *brmctx,
 	case IGMP_HOST_MEMBERSHIP_REPORT:
 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
+		BR_INPUT_SKB_CB(skb)->force_mc_flood = 1;
 		err = br_ip4_multicast_add_group(brmctx, pmctx, ih->group, vid,
 						 src, true);
 		break;
@@ -3855,6 +3856,7 @@  static int br_multicast_ipv4_rcv(struct net_bridge_mcast *brmctx,
 		br_ip4_multicast_query(brmctx, pmctx, skb, vid);
 		break;
 	case IGMP_HOST_LEAVE_MESSAGE:
+		BR_INPUT_SKB_CB(skb)->force_mc_flood = 1;
 		br_ip4_multicast_leave_group(brmctx, pmctx, ih->group, vid, src);
 		break;
 	}
@@ -3910,6 +3912,7 @@  static int br_multicast_ipv6_rcv(struct net_bridge_mcast *brmctx,
 	case ICMPV6_MGM_REPORT:
 		src = eth_hdr(skb)->h_source;
 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
+		BR_INPUT_SKB_CB(skb)->force_mc_flood = 1;
 		err = br_ip6_multicast_add_group(brmctx, pmctx, &mld->mld_mca,
 						 vid, src, true);
 		break;
@@ -3922,6 +3925,7 @@  static int br_multicast_ipv6_rcv(struct net_bridge_mcast *brmctx,
 		break;
 	case ICMPV6_MGM_REDUCTION:
 		src = eth_hdr(skb)->h_source;
+		BR_INPUT_SKB_CB(skb)->force_mc_flood = 1;
 		br_ip6_multicast_leave_group(brmctx, pmctx, &mld->mld_mca, vid,
 					     src);
 		break;
@@ -3944,6 +3948,7 @@  int br_multicast_rcv(struct net_bridge_mcast **brmctx,
 	BR_INPUT_SKB_CB(skb)->igmp = 0;
 	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
 	BR_INPUT_SKB_CB(skb)->force_flood = 0;
+	BR_INPUT_SKB_CB(skb)->force_mc_flood = 0;
 
 	if (!br_opt_get((*brmctx)->br, BROPT_MULTICAST_ENABLED))
 		return 0;
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index c28e0cd0855c..d72a632a1ad2 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -587,6 +587,7 @@  struct br_input_skb_cb {
 	u8 igmp;
 	u8 mrouters_only:1;
 	u8 force_flood:1;
+	u8 force_mc_flood:1;
 #endif
 	u8 proxyarp_replied:1;
 	u8 src_port_isolated:1;
@@ -622,9 +623,11 @@  struct br_input_skb_cb {
 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 # define BR_INPUT_SKB_CB_MROUTERS_ONLY(__skb)	(BR_INPUT_SKB_CB(__skb)->mrouters_only)
 # define BR_INPUT_SKB_CB_FORCE_FLOOD(__skb)	(BR_INPUT_SKB_CB(__skb)->force_flood)
+# define BR_INPUT_SKB_CB_FORCE_MC_FLOOD(__skb)	(BR_INPUT_SKB_CB(__skb)->force_mc_flood)
 #else
 # define BR_INPUT_SKB_CB_MROUTERS_ONLY(__skb)	(0)
 # define BR_INPUT_SKB_CB_FORCE_FLOOD(__skb)	(0)
+# define BR_INPUT_SKB_CB_FORCE_MC_FLOOD(__skb)	(0)
 #endif
 
 #define br_printk(level, br, format, args...)	\