Subject: Re: [syzbot] [bpf?] [net?] BUG: unable to handle kernel NULL pointer dereference in dev_map_hash_update_elem

From: John Fastabend <[email-masked]>
Date: Mon, 26 Feb 2024 13:49:15 -0800

syzbot wrote:
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    70ff1fe626a1 Merge tag 'docs-6.8-fixes3' of git://git.lwn...
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1762045c180000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=4cf52b43f46d820d
> dashboard link: https://syzkaller.appspot.com/bug?extid=8cd36f6b65f3cafd400a
> compiler:       arm-linux-gnueabi-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> userspace arch: arm
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=110cf122180000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=142f6d8c180000
> 
> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/8ead8862021c/non_bootable_disk-70ff1fe6.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/bc398db9fd8c/vmlinux-70ff1fe6.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/6d3f8b72a671/zImage-70ff1fe6.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: [email-masked]
> 

I'll take a look this week if no one beats me to it. Looks like there is
a reproducer so should be able to sort it out.