diff mbox series

[PATCHv4,net,1/2] bonding: reset bond's flags when down link is P2P device

Message ID 20230721040356.3591174-2-liuhangbin@gmail.com (mailing list archive)
State Accepted
Commit da19a2b967cf1e2c426f50d28550d1915214a81d
Delegated to: Netdev Maintainers
Headers show
Series Fix up dev flags when add P2P down link | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1342 this patch: 1342
netdev/cc_maintainers fail 1 blamed authors not CCed: jeff@garzik.org; 2 maintainers not CCed: andy@greyhouse.net jeff@garzik.org
netdev/build_clang success Errors and warnings before: 1365 this patch: 1365
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 success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 1365 this patch: 1365
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 11 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Hangbin Liu July 21, 2023, 4:03 a.m. UTC
When adding a point to point downlink to the bond, we neglected to reset
the bond's flags, which were still using flags like BROADCAST and
MULTICAST. Consequently, this would initiate ARP/DAD for P2P downlink
interfaces, such as when adding a GRE device to the bonding.

To address this issue, let's reset the bond's flags for P2P interfaces.

Before fix:
7: gre0@NONE: <POINTOPOINT,NOARP,SLAVE,UP,LOWER_UP> mtu 1500 qdisc noqueue master bond0 state UNKNOWN group default qlen 1000
    link/gre6 2006:70:10::1 peer 2006:70:10::2 permaddr 167f:18:f188::
8: bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/gre6 2006:70:10::1 brd 2006:70:10::2
    inet6 fe80::200:ff:fe00:0/64 scope link
       valid_lft forever preferred_lft forever

After fix:
7: gre0@NONE: <POINTOPOINT,NOARP,SLAVE,UP,LOWER_UP> mtu 1500 qdisc noqueue master bond2 state UNKNOWN group default qlen 1000
    link/gre6 2006:70:10::1 peer 2006:70:10::2 permaddr c29e:557a:e9d9::
8: bond0: <POINTOPOINT,NOARP,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/gre6 2006:70:10::1 peer 2006:70:10::2
    inet6 fe80::1/64 scope link
       valid_lft forever preferred_lft forever

Reported-by: Liang Li <liali@redhat.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2221438
Fixes: 872254dd6b1f ("net/bonding: Enable bonding to enslave non ARPHRD_ETHER")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
---
v4: no change.
v3: no change.
v2: Add the missed {} after if checking.
---
 drivers/net/bonding/bond_main.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 7a0f25301f7e..484c9e3e5e82 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1508,6 +1508,11 @@  static void bond_setup_by_slave(struct net_device *bond_dev,
 
 	memcpy(bond_dev->broadcast, slave_dev->broadcast,
 		slave_dev->addr_len);
+
+	if (slave_dev->flags & IFF_POINTOPOINT) {
+		bond_dev->flags &= ~(IFF_BROADCAST | IFF_MULTICAST);
+		bond_dev->flags |= (IFF_POINTOPOINT | IFF_NOARP);
+	}
 }
 
 /* On bonding slaves other than the currently active slave, suppress