memory leak in smc_create

Hello,

syzbot found the following crash on:

HEAD commit:    9d234505 Merge tag 'hwmon-for-v5.4-rc6' of git://git.kerne..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10c4e4ece00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9bbb8fba7651600b
dashboard link: https://syzkaller.appspot.com/bug?extid=4b73ad6fc767e576e275
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16f6dc68e00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=124c8934e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+4b73ad6fc767e576e275@syzkaller.appspotmail.com

executing program
executing program
BUG: memory leak
unreferenced object 0xffff888121495640 (size 1376):
   comm "syz-executor038", pid 6906, jiffies 4294945610 (age 13.070s)
   hex dump (first 32 bytes):
     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
     2b 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00  +..@............
   backtrace:
     [<00000000930d5c59>] kmemleak_alloc_recursive  
include/linux/kmemleak.h:43 [inline]
     [<00000000930d5c59>] slab_post_alloc_hook mm/slab.h:586 [inline]
     [<00000000930d5c59>] slab_alloc mm/slab.c:3319 [inline]
     [<00000000930d5c59>] kmem_cache_alloc+0x13f/0x2c0 mm/slab.c:3483
     [<00000000249c491d>] sk_prot_alloc+0x41/0x170 net/core/sock.c:1599
     [<0000000035a03310>] sk_alloc+0x35/0x2f0 net/core/sock.c:1659
     [<00000000e79e3c49>] smc_sock_alloc+0x4a/0x1a0 net/smc/af_smc.c:222
     [<0000000079a84e95>] smc_create+0x6b/0x160 net/smc/af_smc.c:1979
     [<00000000607f3b4e>] __sock_create+0x164/0x250 net/socket.c:1418
     [<00000000fbb3e501>] sock_create net/socket.c:1469 [inline]
     [<00000000fbb3e501>] __sys_socket+0x69/0x110 net/socket.c:1511
     [<00000000d697ec9a>] __do_sys_socket net/socket.c:1520 [inline]
     [<00000000d697ec9a>] __se_sys_socket net/socket.c:1518 [inline]
     [<00000000d697ec9a>] __x64_sys_socket+0x1e/0x30 net/socket.c:1518
     [<00000000dcb4ba7a>] do_syscall_64+0x73/0x1f0  
arch/x86/entry/common.c:290
     [<000000009386b4f0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9



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