batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0
==================================================================
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
BUG: KASAN: null-ptr-deref in memcpy include/linux/string.h:347 [inline]
BUG: KASAN: null-ptr-deref in llcp_sock_getname+0x37b/0x490 net/nfc/llcp_sock.c:532
IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready
Read of size 29 at addr           (null) by task syz-executor.1/7753
batman_adv: batadv0: Interface activated: batadv_slave_0

CPU: 0 PID: 7753 Comm: syz-executor.1 Not tainted 4.14.177-syzkaller #0
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x13e/0x194 lib/dump_stack.c:58
 kasan_report_error mm/kasan/report.c:349 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0x127/0x2ae mm/kasan/report.c:393
 memcpy+0x20/0x50 mm/kasan/kasan.c:302
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1
 memcpy include/linux/string.h:347 [inline]
 llcp_sock_getname+0x37b/0x490 net/nfc/llcp_sock.c:532
 SYSC_getsockname+0xff/0x1c0 net/socket.c:1683
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c829
RSP: 002b:00007f961091ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000033
RAX: ffffffffffffffda RBX: 00000000004dce40 RCX: 000000000045c829
RDX: 0000000020000100 RSI: 0000000020000180 RDI: 000000000000000a
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000010e R14: 00000000004c38dd R15: 00007f961091f6d4
==================================================================