From: David Laight > Sent: 26 September 2020 12:16 > To: 'syzbot' <syzbot+51177e4144d764827c45@xxxxxxxxxxxxxxxxxxxxxxxxx>; linux-fsdevel@xxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx; syzkaller-bugs@xxxxxxxxxxxxxxxx; viro@xxxxxxxxxxxxxxxxxx > Subject: RE: WARNING in __kernel_read (2) > > > From: syzbot <syzbot+51177e4144d764827c45@xxxxxxxxxxxxxxxxxxxxxxxxx> > > Sent: 26 September 2020 03:58 > > To: linux-fsdevel@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; syzkaller-bugs@xxxxxxxxxxxxxxxx; > > viro@xxxxxxxxxxxxxxxxxx > > Subject: WARNING in __kernel_read (2) > > I suspect this is calling finit_module() on an fd > that doesn't have read permissions. Code inspection also seems to imply that the check means the exec() also requires read permissions on the file. This isn't traditionally true. suid #! scripts are particularly odd without 'owner read' (everyone except the owner can run them!). David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
