linux-4.14.y build error

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: bae31eef Linux 4.14.200
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=129565ef900000
kernel config: https://syzkaller.appspot.com/x/.config?x=256c20b97e0f058
dashboard link: https://syzkaller.appspot.com/bug?extid=e51f376a7d61aef3a080
compiler: gcc (GCC) 10.1.0-syz 20200507

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e51f37...@syzkaller.appspotmail.com

lib/string.c:259: undefined reference to `__ubsan_handle_nonnull_return_v1'

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[Dmitry Vyukov]

The latest bug in this bucket was fixed by:
https://github.com/google/syzkaller/commit/fea47c014be7a00a32ab016b946c0a77f32c1f40
and ubsan was fixed by something as well.

#syz invalid