memory leak in macvlan_hash_add

memory leak in macvlan_hash_add_source
Status: upstream: reported C repro on 2020/06/18 04:04
Reported-by: syzbot+62100d232f618b7da606@syzkaller.appspotmail.com
First crash: 705d, last: 705d

Patch testing requests:
Created	Duration	User	Patch	Repo	Result
2021/04/11 11:36	15m	phil@philpotter.co.uk		upstream	OK

Sample crash report:

BUG: memory leak
unreferenced object 0xffff888115ac4080 (size 64):
  comm "syz-executor882", pid 6646, jiffies 4294954688 (age 14.840s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 20 ee 41 15 81 88 ff ff  ........ .A.....
    00 09 92 15 81 88 ff ff aa aa aa aa aa 23 00 00  .............#..
  backtrace:
    [<00000000fe90004e>] kmalloc include/linux/slab.h:555 [inline]
    [<00000000fe90004e>] macvlan_hash_add_source+0x52/0xe0 drivers/net/macvlan.c:161
    [<000000005aee7a07>] macvlan_changelink_sources+0x8a/0x1f0 drivers/net/macvlan.c:1355
    [<00000000e0e074d6>] macvlan_common_newlink+0x21a/0x570 drivers/net/macvlan.c:1463
    [<00000000c89166a4>] __rtnl_newlink+0x843/0xb10 net/core/rtnetlink.c:3340
    [<000000009677515c>] rtnl_newlink+0x49/0x70 net/core/rtnetlink.c:3398
    [<00000000fab710c9>] rtnetlink_rcv_msg+0x173/0x4b0 net/core/rtnetlink.c:5461
    [<00000000d3f45a45>] netlink_rcv_skb+0x5a/0x180 net/netlink/af_netlink.c:2469
    [<00000000b9db6049>] netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
    [<00000000b9db6049>] netlink_unicast+0x20a/0x2f0 net/netlink/af_netlink.c:1329
    [<000000006a00463c>] netlink_sendmsg+0x2b5/0x560 net/netlink/af_netlink.c:1918
    [<00000000a31e18a9>] sock_sendmsg_nosec net/socket.c:652 [inline]
    [<00000000a31e18a9>] sock_sendmsg+0x4c/0x60 net/socket.c:672
    [<000000000ca330a5>] ____sys_sendmsg+0x118/0x2f0 net/socket.c:2352
    [<000000006a5fc310>] ___sys_sendmsg+0x8a/0xd0 net/socket.c:2406
    [<000000004d3b2570>] __sys_sendmmsg+0xda/0x230 net/socket.c:2496
    [<00000000a524412c>] __do_sys_sendmmsg net/socket.c:2525 [inline]
    [<00000000a524412c>] __se_sys_sendmmsg net/socket.c:2522 [inline]
    [<00000000a524412c>] __x64_sys_sendmmsg+0x24/0x30 net/socket.c:2522
    [<00000000333adef2>] do_syscall_64+0x6e/0x220 arch/x86/entry/common.c:295
    [<00000000df7893d8>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci-upstream-gce-leak	2020/06/14 03:46	upstream	7ae77150d94d	dbce178a	.config	log	report	syz	C