From fc4aa1ca1628d31d1e2770b96a3bd8e25eef118d Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Thu, 7 Feb 2019 12:18:02 +0000 Subject: [PATCH] net: vxlan: Free a leaked vetoed multicast rdst When an rdst is rejected by a driver, the current code removes it from the remote list, but neglects to free it. This is triggered by tools/testing/selftests/drivers/net/mlxsw/vxlan_fdb_veto.sh and shows as the following kmemleak trace: unreferenced object 0xffff88817fa3d888 (size 96): comm "softirq", pid 0, jiffies 4372702718 (age 165.252s) hex dump (first 32 bytes): 02 00 00 00 c6 33 64 03 80 f5 a2 61 81 88 ff ff .....3d....a.... 06 df 71 ae ff ff ff ff 0c 00 00 00 04 d2 6a 6b ..q...........jk backtrace: [<00000000296b27ac>] kmem_cache_alloc_trace+0x1ae/0x370 [<0000000075c86dc6>] vxlan_fdb_append.part.12+0x62/0x3b0 [vxlan] [<00000000e0414b63>] vxlan_fdb_update+0xc61/0x1020 [vxlan] [<00000000f330c4bd>] vxlan_fdb_add+0x2e8/0x3d0 [vxlan] [<0000000008f81c2c>] rtnl_fdb_add+0x4c2/0xa10 [<00000000bdc4b270>] rtnetlink_rcv_msg+0x6dd/0x970 [<000000006701f2ce>] netlink_rcv_skb+0x290/0x410 [<00000000c08a5487>] rtnetlink_rcv+0x15/0x20 [<00000000d5f54b1e>] netlink_unicast+0x43f/0x5e0 [<00000000db4336bb>] netlink_sendmsg+0x789/0xcd0 [<00000000e1ee26b6>] sock_sendmsg+0xba/0x100 [<00000000ba409802>] ___sys_sendmsg+0x631/0x960 [<000000003c332113>] __sys_sendmsg+0xea/0x180 [<00000000f4139144>] __x64_sys_sendmsg+0x78/0xb0 [<000000006d1ddc59>] do_syscall_64+0x94/0x410 [<00000000c8defa9a>] entry_SYSCALL_64_after_hwframe+0x49/0xbe Move vxlan_dst_free() up and schedule a call thereof to plug this leak. Fixes: 61f46fe8c646 ("vxlan: Allow vetoing of FDB notifications") Signed-off-by: Petr Machata Acked-by: Jiri Pirko Signed-off-by: David S. Miller --- drivers/net/vxlan.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index ef45c3c925be..c0cd1c022e77 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -869,6 +869,14 @@ static void vxlan_fdb_destroy(struct vxlan_dev *vxlan, struct vxlan_fdb *f, call_rcu(&f->rcu, vxlan_fdb_free); } +static void vxlan_dst_free(struct rcu_head *head) +{ + struct vxlan_rdst *rd = container_of(head, struct vxlan_rdst, rcu); + + dst_cache_destroy(&rd->dst_cache); + kfree(rd); +} + static int vxlan_fdb_update_existing(struct vxlan_dev *vxlan, union vxlan_addr *ip, __u16 state, __u16 flags, @@ -941,8 +949,10 @@ static int vxlan_fdb_update_existing(struct vxlan_dev *vxlan, err_notify: if ((flags & NLM_F_REPLACE) && rc) *rd = oldrd; - else if ((flags & NLM_F_APPEND) && rc) + else if ((flags & NLM_F_APPEND) && rc) { list_del_rcu(&rd->list); + call_rcu(&rd->rcu, vxlan_dst_free); + } return err; } @@ -1013,14 +1023,6 @@ static int vxlan_fdb_update(struct vxlan_dev *vxlan, } } -static void vxlan_dst_free(struct rcu_head *head) -{ - struct vxlan_rdst *rd = container_of(head, struct vxlan_rdst, rcu); - - dst_cache_destroy(&rd->dst_cache); - kfree(rd); -} - static void vxlan_fdb_dst_destroy(struct vxlan_dev *vxlan, struct vxlan_fdb *f, struct vxlan_rdst *rd, bool swdev_notify) {