6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ido Schimmel idosch@nvidia.com
[ Upstream commit 087a9eb9e5978e3ba362e1163691e41097e8ca20 ]
When a VNI is deleted from a VXLAN device in 'vnifilter' mode, the FDB entry associated with the default remote (assuming one was configured) is deleted without holding the hash lock. This is wrong and will result in a warning [1] being generated by the lockdep annotation that was added by commit ebe642067455 ("vxlan: Create wrappers for FDB lookup").
Reproducer:
# ip link add vx0 up type vxlan dstport 4789 external vnifilter local 192.0.2.1 # bridge vni add vni 10010 remote 198.51.100.1 dev vx0 # bridge vni del vni 10010 dev vx0
Fix by acquiring the hash lock before the deletion and releasing it afterwards. Blame the original commit that introduced the issue rather than the one that exposed it.
[1] WARNING: CPU: 3 PID: 392 at drivers/net/vxlan/vxlan_core.c:417 vxlan_find_mac+0x17f/0x1a0 [...] RIP: 0010:vxlan_find_mac+0x17f/0x1a0 [...] Call Trace: <TASK> __vxlan_fdb_delete+0xbe/0x560 vxlan_vni_delete_group+0x2ba/0x940 vxlan_vni_del.isra.0+0x15f/0x580 vxlan_process_vni_filter+0x38b/0x7b0 vxlan_vnifilter_process+0x3bb/0x510 rtnetlink_rcv_msg+0x2f7/0xb70 netlink_rcv_skb+0x131/0x360 netlink_unicast+0x426/0x710 netlink_sendmsg+0x75a/0xc20 __sock_sendmsg+0xc1/0x150 ____sys_sendmsg+0x5aa/0x7b0 ___sys_sendmsg+0xfc/0x180 __sys_sendmsg+0x121/0x1b0 do_syscall_64+0xbb/0x1d0 entry_SYSCALL_64_after_hwframe+0x4b/0x53
Fixes: f9c4bb0b245c ("vxlan: vni filtering support on collect metadata device") Signed-off-by: Ido Schimmel idosch@nvidia.com Reviewed-by: Nikolay Aleksandrov razor@blackwall.org Link: https://patch.msgid.link/20250423145131.513029-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/vxlan/vxlan_vnifilter.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/net/vxlan/vxlan_vnifilter.c b/drivers/net/vxlan/vxlan_vnifilter.c index 6e6e9f05509ab..06d19e90eadb5 100644 --- a/drivers/net/vxlan/vxlan_vnifilter.c +++ b/drivers/net/vxlan/vxlan_vnifilter.c @@ -627,7 +627,11 @@ static void vxlan_vni_delete_group(struct vxlan_dev *vxlan, * default dst remote_ip previously added for this vni */ if (!vxlan_addr_any(&vninode->remote_ip) || - !vxlan_addr_any(&dst->remote_ip)) + !vxlan_addr_any(&dst->remote_ip)) { + u32 hash_index = fdb_head_index(vxlan, all_zeros_mac, + vninode->vni); + + spin_lock_bh(&vxlan->hash_lock[hash_index]); __vxlan_fdb_delete(vxlan, all_zeros_mac, (vxlan_addr_any(&vninode->remote_ip) ? dst->remote_ip : vninode->remote_ip), @@ -635,6 +639,8 @@ static void vxlan_vni_delete_group(struct vxlan_dev *vxlan, vninode->vni, vninode->vni, dst->remote_ifindex, true); + spin_unlock_bh(&vxlan->hash_lock[hash_index]); + }
if (vxlan->dev->flags & IFF_UP) { if (vxlan_addr_multicast(&vninode->remote_ip) &&