On Wed, Jun 23, 2021 at 04:26:35PM +0200, Pavel Machek wrote: > Hi! > > > > There is a panic in socket ioctl cmd SIOCGSKNS when NET_NS is not enabled. > > The reason is that nsfs tries to access ns->ops but the proc_ns_operations > > is not implemented in this case. > > > > [7.670023] Unable to handle kernel NULL pointer dereference at virtual address 00000010 > > [7.670268] pgd = 32b54000 > > [7.670544] [00000010] *pgd=00000000 > > [7.671861] Internal error: Oops: 5 [#1] SMP ARM > > [7.672315] Modules linked in: > > [7.672918] CPU: 0 PID: 1 Comm: systemd Not tainted 5.13.0-rc3-00375-g6799d4f2da49 #16 > > [7.673309] Hardware name: Generic DT based system > > [7.673642] PC is at nsfs_evict+0x24/0x30 > > [7.674486] LR is at clear_inode+0x20/0x9c > > > > The same to tun SIOCGSKNS command. > > > > To fix this problem, we make get_net_ns() return -EINVAL when NET_NS is > > disabled. Meanwhile move it to right place net/core/net_namespace.c. > > -EINVAL sounds like wrong error code for valid operation kernel was > configured to do. -ENOTSUPP? > This is to align with the existing code which returns -EINVAL. For the issue we fixed, yes, -EOPNOTSUPP (not -ENOTSUPP) should be better. > Best regards, > Pavel > > -- > http://www.livejournal.com/~pavelmachek -- Cheers, Changbin Du
