[PATCH 4.14 06/34] net: hsr: fix memory leak in hsr_dev_finalize()

Greg Kroah-Hartman
2019-03-18T09:35:59Z

From: Mao Wenan <maowenan@huawei.com>

[ Upstream commit 3dc6da493a29dbeda9f13b637bd9c02c414b2261 ]

If hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER) failed to
add port, it directly returns res and forgets to free the node
that allocated in hsr_create_self_node(), and forgets to delete
the node->mac_list linked in hsr->self_node_db.

BUG: memory leak
unreferenced object 0xffff8881cfa0c780 (size 64):
comm "syz-executor.0", pid 2077, jiffies 4294717969 (age 2415.377s)
hex dump (first 32 bytes):
e0 c7 a0 cf 81 88 ff ff 00 02 00 00 00 00 ad de ................
00 e6 49 cd 81 88 ff ff c0 9b 87 d0 81 88 ff ff ..I.............
backtrace:
[<00000000e2ff5070>] hsr_dev_finalize+0x736/0x960 [hsr]
[<000000003ed2e597>] hsr_newlink+0x2b2/0x3e0 [hsr]
[<000000003fa8c6b6>] __rtnl_newlink+0xf1f/0x1600 net/core/rtnetlink.c:3182
[<000000001247a7ad>] rtnl_newlink+0x66/0x90 net/core/rtnetlink.c:3240
[<00000000e7d1b61d>] rtnetlink_rcv_msg+0x54e/0xb90 net/core/rtnetlink.c:5130
[<000000005556bd3a>] netlink_rcv_skb+0x129/0x340 net/netlink/af_netlink.c:2477
[<00000000741d5ee6>] netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
[<00000000741d5ee6>] netlink_unicast+0x49a/0x650 net/netlink/af_netlink.c:1336
[<000000009d56f9b7>] netlink_sendmsg+0x88b/0xdf0 net/netlink/af_netlink.c:1917
[<0000000046b35c59>] sock_sendmsg_nosec net/socket.c:621 [inline]
[<0000000046b35c59>] sock_sendmsg+0xc3/0x100 net/socket.c:631
[<00000000d208adc9>] __sys_sendto+0x33e/0x560 net/socket.c:1786
[<00000000b582837a>] __do_sys_sendto net/socket.c:1798 [inline]
[<00000000b582837a>] __se_sys_sendto net/socket.c:1794 [inline]
[<00000000b582837a>] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:1794
[<00000000c866801d>] do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
[<00000000fea382d9>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[<00000000e01dacb3>] 0xffffffffffffffff

Fixes: c5a759117210 ("net/hsr: Use list_head (and rcu) instead of array for slave devices.")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Mao Wenan <maowenan@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/hsr/hsr_device.c | 4 +++-
net/hsr/hsr_framereg.c | 12 ++++++++++++
net/hsr/hsr_framereg.h | 1 +
3 files changed, 16 insertions(+), 1 deletion(-)

--- a/net/hsr/hsr_device.c
+++ b/net/hsr/hsr_device.c
@@ -487,7 +487,7 @@ int hsr_dev_finalize(struct net_device *

res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER);
if (res)
- return res;
+ goto err_add_port;

res = register_netdevice(hsr_dev);
if (res)
@@ -507,6 +507,8 @@ int hsr_dev_finalize(struct net_device *
fail:
hsr_for_each_port(hsr, port)
hsr_del_port(port);
+err_add_port:
+ hsr_del_node(&hsr->self_node_db);

return res;
}
--- a/net/hsr/hsr_framereg.c
+++ b/net/hsr/hsr_framereg.c
@@ -124,6 +124,18 @@ int hsr_create_self_node(struct list_hea
return 0;
}

+void hsr_del_node(struct list_head *self_node_db)
+{
+ struct hsr_node *node;
+
+ rcu_read_lock();
+ node = list_first_or_null_rcu(self_node_db, struct hsr_node, mac_list);
+ rcu_read_unlock();
+ if (node) {
+ list_del_rcu(&node->mac_list);
+ kfree(node);
+ }
+}

/* Allocate an hsr_node and add it to node_db. 'addr' is the node's AddressA;
* seq_out is used to initialize filtering of outgoing duplicate frames
--- a/net/hsr/hsr_framereg.h
+++ b/net/hsr/hsr_framereg.h
@@ -16,6 +16,7 @@

struct hsr_node;

+void hsr_del_node(struct list_head *self_node_db);
struct hsr_node *hsr_add_node(struct list_head *node_db, unsigned char addr[],
u16 seq_out);
struct hsr_node *hsr_get_node(struct hsr_port *port, struct sk_buff *skb,