| From foo@baz Wed 29 Jul 2020 11:19:56 AM CEST |
| From: Weilong Chen <chenweilong@huawei.com> |
| Date: Wed, 15 Jul 2020 20:58:10 +0800 |
| Subject: rtnetlink: Fix memory(net_device) leak when ->newlink fails |
| |
| From: Weilong Chen <chenweilong@huawei.com> |
| |
| [ Upstream commit cebb69754f37d68e1355a5e726fdac317bcda302 ] |
| |
| When vlan_newlink call register_vlan_dev fails, it might return error |
| with dev->reg_state = NETREG_UNREGISTERED. The rtnl_newlink should |
| free the memory. But currently rtnl_newlink only free the memory which |
| state is NETREG_UNINITIALIZED. |
| |
| BUG: memory leak |
| unreferenced object 0xffff8881051de000 (size 4096): |
| comm "syz-executor139", pid 560, jiffies 4294745346 (age 32.445s) |
| hex dump (first 32 bytes): |
| 76 6c 61 6e 32 00 00 00 00 00 00 00 00 00 00 00 vlan2........... |
| 00 45 28 03 81 88 ff ff 00 00 00 00 00 00 00 00 .E(............. |
| backtrace: |
| [<0000000047527e31>] kmalloc_node include/linux/slab.h:578 [inline] |
| [<0000000047527e31>] kvmalloc_node+0x33/0xd0 mm/util.c:574 |
| [<000000002b59e3bc>] kvmalloc include/linux/mm.h:753 [inline] |
| [<000000002b59e3bc>] kvzalloc include/linux/mm.h:761 [inline] |
| [<000000002b59e3bc>] alloc_netdev_mqs+0x83/0xd90 net/core/dev.c:9929 |
| [<000000006076752a>] rtnl_create_link+0x2c0/0xa20 net/core/rtnetlink.c:3067 |
| [<00000000572b3be5>] __rtnl_newlink+0xc9c/0x1330 net/core/rtnetlink.c:3329 |
| [<00000000e84ea553>] rtnl_newlink+0x66/0x90 net/core/rtnetlink.c:3397 |
| [<0000000052c7c0a9>] rtnetlink_rcv_msg+0x540/0x990 net/core/rtnetlink.c:5460 |
| [<000000004b5cb379>] netlink_rcv_skb+0x12b/0x3a0 net/netlink/af_netlink.c:2469 |
| [<00000000c71c20d3>] netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] |
| [<00000000c71c20d3>] netlink_unicast+0x4c6/0x690 net/netlink/af_netlink.c:1329 |
| [<00000000cca72fa9>] netlink_sendmsg+0x735/0xcc0 net/netlink/af_netlink.c:1918 |
| [<000000009221ebf7>] sock_sendmsg_nosec net/socket.c:652 [inline] |
| [<000000009221ebf7>] sock_sendmsg+0x109/0x140 net/socket.c:672 |
| [<000000001c30ffe4>] ____sys_sendmsg+0x5f5/0x780 net/socket.c:2352 |
| [<00000000b71ca6f3>] ___sys_sendmsg+0x11d/0x1a0 net/socket.c:2406 |
| [<0000000007297384>] __sys_sendmsg+0xeb/0x1b0 net/socket.c:2439 |
| [<000000000eb29b11>] do_syscall_64+0x56/0xa0 arch/x86/entry/common.c:359 |
| [<000000006839b4d0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 |
| |
| Fixes: cb626bf566eb ("net-sysfs: Fix reference count leak") |
| Reported-by: Hulk Robot <hulkci@huawei.com> |
| Signed-off-by: Weilong Chen <chenweilong@huawei.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/core/rtnetlink.c | 3 ++- |
| 1 file changed, 2 insertions(+), 1 deletion(-) |
| |
| --- a/net/core/rtnetlink.c |
| +++ b/net/core/rtnetlink.c |
| @@ -3231,7 +3231,8 @@ replay: |
| */ |
| if (err < 0) { |
| /* If device is not registered at all, free it now */ |
| - if (dev->reg_state == NETREG_UNINITIALIZED) |
| + if (dev->reg_state == NETREG_UNINITIALIZED || |
| + dev->reg_state == NETREG_UNREGISTERED) |
| free_netdev(dev); |
| goto out; |
| } |