RE: WARNING in sk_psock_drop

[John Fastabend]

syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    93ad0f96 net: wan: lapbether.c: Use built-in RCU list chec..
> git tree:       net
> console output: https://syzkaller.appspot.com/x/log.txt?x=132caa76e00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=7e89bd00623fe71e
> dashboard link: https://syzkaller.appspot.com/bug?extid=d73682fcf7fee6982fe3
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> 
> Unfortunately, I don't have any reproducer for this crash yet.
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+d73682fcf7fee6982fe3@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> ------------[ cut here ]------------
> WARNING: CPU: 1 PID: 11793 at include/net/sock.h:1578 sock_owned_by_me  
> include/net/sock.h:1578 [inline]
> WARNING: CPU: 1 PID: 11793 at include/net/sock.h:1578  
> sk_psock_drop+0x5fa/0x7f0 net/core/skmsg.c:597
> Kernel panic - not syncing: panic_on_warn set ...
> CPU: 1 PID: 11793 Comm: syz-executor.3 Not tainted 5.5.0-rc5-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
> Google 01/01/2011

I recently added this sock_owned_by_me so I'll take a look. Thanks for
the report. Seems we have a case where its not held.