memory leak in macvlan_hash_add_source

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 7ae77150 Merge tag 'powerpc-5.8-1' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11fbb456100000
kernel config: https://syzkaller.appspot.com/x/.config?x=9a1aa05456dfd557
dashboard link: https://syzkaller.appspot.com/bug?extid=62100d232f618b7da606
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=163092a9100000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12caed7a100000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+62100d...@syzkaller.appspotmail.com

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



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[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.